diff --git a/ReadMe.txt b/ReadMe.txt index 66ce874..a00778d 100644 --- a/ReadMe.txt +++ b/ReadMe.txt @@ -65,6 +65,7 @@ CHANGES Version 2.0 (2020-11-XX) +- Updated source code from Eric Rechlin's Emu48 version 1.62+ that was merged from Christoph Gießelink's Emu48 version 1.63. - For the HP49/50 port 2, it is now possible to load a new Flash ROM file (It fully replaces the ROM). - Replaces the haptic feedback switch with a slider to adjust the vibration duration. - Fix transparency issue (RGB -> BGR). diff --git a/app/CMakeLists.txt b/app/CMakeLists.txt index 4cd1690..c16d28f 100644 --- a/app/CMakeLists.txt +++ b/app/CMakeLists.txt @@ -53,7 +53,7 @@ add_library( # Sets the name of the library. src/main/cpp/core/disrpl.c # src/main/cpp/core/Emu48.c #-> To rewrite src/main/cpp/core/engine.c - src/main/cpp/core/external.c +# src/main/cpp/core/external.c # Removed in Emu48+ for Windows version 1.62+ src/main/cpp/core/fetch.c src/main/cpp/core/files.c src/main/cpp/core/i28f160.c diff --git a/app/src/main/assets/ReadMe.txt b/app/src/main/assets/ReadMe.txt index 4c596b3..e621dcf 100644 --- a/app/src/main/assets/ReadMe.txt +++ b/app/src/main/assets/ReadMe.txt @@ -65,6 +65,7 @@ CHANGES Version 2.0 (2020-11-XX) +- Updated source code from Eric Rechlin's Emu48 version 1.62+ that was merged from Christoph Gießelink's Emu48 version 1.63. - For the HP49/50 port 2, it is now possible to load a new Flash ROM file (It fully replaces the ROM). - Replaces the haptic feedback switch with a slider to adjust the vibration duration. - Fix transparency issue (RGB -> BGR). diff --git a/app/src/main/cpp/android-emu.c b/app/src/main/cpp/android-emu.c index 9491693..a11897a 100644 --- a/app/src/main/cpp/android-emu.c +++ b/app/src/main/cpp/android-emu.c @@ -279,7 +279,7 @@ static LRESULT OnPaint(HWND hWindow) GdiFlush(); } LeaveCriticalSection(&csGDILock); - UpdateAnnunciators(); + UpdateAnnunciators(0x3F); RefreshButtons(&rcMainPaint); } EndPaint(hWindow, &Paint); diff --git a/app/src/main/cpp/core/Emu48.c b/app/src/main/cpp/core/Emu48.c index 8ef5bf6..d35e267 100644 --- a/app/src/main/cpp/core/Emu48.c +++ b/app/src/main/cpp/core/Emu48.c @@ -13,7 +13,7 @@ #include "kml.h" #include "debugger.h" -#define VERSION "1.61+" +#define VERSION "1.62+" #ifdef _DEBUG LPCTSTR szNoTitle = _T("Emu48 ")_T(VERSION)_T(" Debug"); @@ -904,7 +904,7 @@ static LRESULT OnPaint(HWND hWindow) GdiFlush(); } LeaveCriticalSection(&csGDILock); - UpdateAnnunciators(); + UpdateAnnunciators(0x3F); RefreshButtons(&rcMainPaint); } EndPaint(hWindow, &Paint); diff --git a/app/src/main/cpp/core/Emu48.h b/app/src/main/cpp/core/Emu48.h index 965c69a..f438d2a 100644 --- a/app/src/main/cpp/core/Emu48.h +++ b/app/src/main/cpp/core/Emu48.h @@ -52,7 +52,6 @@ #define DISP_POINTER 0x01 // defines for display area #define DISP_MAIN 0x02 #define DISP_MENUE 0x04 -#define DISP_ANNUN 0x08 #define ROMPAGESIZE (1<<12) // ROM dirty page size in nibbles @@ -182,7 +181,7 @@ extern VOID UpdateMenuDisplay(VOID); extern VOID RefreshDisp0(); // CdB for HP: add apples display management extern VOID WriteToMainDisplay(LPBYTE a, DWORD d, UINT s); extern VOID WriteToMenuDisplay(LPBYTE a, DWORD d, UINT s); -extern VOID UpdateAnnunciators(VOID); +extern VOID UpdateAnnunciators(DWORD dwUpdateMask); extern VOID ResizeWindow(VOID); // Engine.c @@ -374,10 +373,6 @@ extern DWORD RPL_Pick(UINT l); extern VOID RPL_Replace(DWORD n); extern VOID RPL_Push(UINT l,DWORD n); -// External.c -extern VOID External(CHIPSET* w); -extern VOID RCKBp(CHIPSET* w); - // SndEnum.c extern VOID SetSoundDeviceList(HWND hWnd,UINT uDeviceID); diff --git a/app/src/main/cpp/core/apple.c b/app/src/main/cpp/core/apple.c index 348cac6..90da4d7 100644 --- a/app/src/main/cpp/core/apple.c +++ b/app/src/main/cpp/core/apple.c @@ -4,7 +4,7 @@ * This file is part of Emu48 * * Copyright (C) 2005 CdB for HP - * Copyright (C) 2006 Christoph Gie�elink + * Copyright (C) 2006 Christoph Gießelink * */ #include "pch.h" @@ -20,7 +20,7 @@ #pragma intrinsic(memset,memcpy) -#include "ops.h" +#include "Ops.h" // // ROM buffer access functions @@ -158,6 +158,35 @@ VOID o80B40(VOID) return; } +// BEEP2 +VOID o80B50(CHIPSET* w) +{ + BYTE fbeep; + DWORD freq,dur; + + freq = Npack(w->D,5); // frequency in Hz + dur = Npack(w->C,5); // duration in ms + Nread(&fbeep,0x80F0F,1); // fetch system flags -53 to -56 + + w->carry = TRUE; // setting of no beep + if (!(fbeep & 0x8) && freq) // bit -56 clear and frequency > 0 Hz + { + if (freq > 4400) freq = 4400; // high limit of HP (SX) + + SoundBeep(freq,dur); // beeping + + // estimate cpu cycles for beeping time (4MHz) + w->cycles += dur * 4000; + + // original routine return with... + w->P = 0; // P=0 + w->intk = TRUE; // INTON + w->carry = FALSE; // RTNCC + } + w->pc = rstkpop(); + return; +} + // MOVEDOWN VOID o80B60(VOID) { @@ -230,6 +259,38 @@ VOID o80B80(VOID) return; } +// RCKBp +VOID o80B90(CHIPSET* w) // ROM Check Beep patch +{ + DWORD dw2F,dwCpuFreq; + DWORD freq,dur; + BYTE f,d; + + f = w->C[1]; // f = freq ctl + d = w->C[0]; // d = duration ctl + + // CPU strobe frequency @ RATE 27 = 3.67MHz + // CPU strobe frequency @ RATE 29 = 3.93MHz + dwCpuFreq = ((27 + 1) * 524288) >> 2; + + dw2F = f * 180 + 367; // F=f*90+183.5 + + freq = dwCpuFreq / dw2F; + dur = (dw2F * (256 - 16 * d)) * 1000 / 2 / dwCpuFreq; + + if (freq > 4400) freq = 4400; // high limit of HP + + SoundBeep(freq,dur); // beeping + + // estimate cpu cycles for beeping time (4MHz) + w->cycles += dur * 4000; + + w->P = 0; // P=0 + w->carry = FALSE; // RTNCC + w->pc = rstkpop(); + return; +} + // setup basic memory configuration VOID o80B04(VOID) { @@ -327,11 +388,11 @@ VOID o80BExt(LPBYTE I) // Saturnator extentions case 0x00: o80B00(); break; // RPL2 (preserve Carry) case 0x03: o80B30(); break; // FALSE case 0x04: o80B40(); break; // DOFALSE - case 0x05: External(&w); PCHANGED; break; // BEEP2 implemented using Emu48's beep + case 0x05: o80B50(&w); PCHANGED; break; // BEEP2 implemented using Emu48's beep case 0x06: o80B60(); break; // MOVEDOWN case 0x07: o80B70(); break; // MOVEUP case 0x08: o80B80(); break; // CREATETEMP - case 0x09: RCKBp(&w); PCHANGED; break; // RCKBp + case 0x09: o80B90(&w); PCHANGED; break; // RCKBp (ROM Check Beep patch) case 0x0A: break; // KEYDN not implemented case 0x0B: break; // no doslow implemented case 0x10: // simulate off function diff --git a/app/src/main/cpp/core/apple.h b/app/src/main/cpp/core/apple.h index c893fbe..181177b 100644 --- a/app/src/main/cpp/core/apple.h +++ b/app/src/main/cpp/core/apple.h @@ -10,9 +10,11 @@ extern VOID o80B00(VOID); extern VOID o80B30(VOID); extern VOID o80B40(VOID); +extern VOID o80B50(CHIPSET* w); extern VOID o80B60(VOID); extern VOID o80B70(VOID); extern VOID o80B80(VOID); +extern VOID o80B90(CHIPSET* w); extern VOID o80B04(VOID); extern VOID o80B14(VOID); extern VOID o80B24(VOID); diff --git a/app/src/main/cpp/core/display.c b/app/src/main/cpp/core/display.c index 74a5a68..2c1bffe 100644 --- a/app/src/main/cpp/core/display.c +++ b/app/src/main/cpp/core/display.c @@ -589,21 +589,26 @@ VOID WriteToMenuDisplay(LPBYTE a, DWORD d, UINT s) return; } -VOID UpdateAnnunciators(VOID) +VOID UpdateAnnunciators(DWORD dwUpdateMask) { BYTE c; + UINT i; c = (BYTE)(Chipset.IORam[ANNCTRL] | (Chipset.IORam[ANNCTRL+1]<<4)); // switch annunciators off if timer stopped if ((c & AON) == 0 || (Chipset.IORam[TIMER2_CTRL] & RUN) == 0) c = 0; - DrawAnnunciator(1,c&LA1); - DrawAnnunciator(2,c&LA2); - DrawAnnunciator(3,c&LA3); - DrawAnnunciator(4,c&LA4); - DrawAnnunciator(5,c&LA5); - DrawAnnunciator(6,c&LA6); + for (i = 1; i <= 6; ++i) + { + if ((dwUpdateMask & 0x1) != 0) // annunciator changed? + { + DrawAnnunciator(i,c & 0x1); + } + dwUpdateMask >>= 1; + c >>= 1; + } + _ASSERT(dwUpdateMask == 0); return; } diff --git a/app/src/main/cpp/core/engine.c b/app/src/main/cpp/core/engine.c index 62c772c..ce5f343 100644 --- a/app/src/main/cpp/core/engine.c +++ b/app/src/main/cpp/core/engine.c @@ -73,7 +73,7 @@ static DWORD dwOldCyc; // cpu cycles at last event static DWORD dwSpeedRef; // timer value at last event static DWORD dwTickRef; // sample timer ticks -#include "ops.h" +#include "Ops.h" // save last instruction in circular instruction buffer static __inline VOID SaveInstrAddr(DWORD dwAddr) @@ -285,7 +285,6 @@ static __inline VOID CheckDisp(BOOL bSync) _ASSERT((disp & DISP_POINTER) == 0); // display pointer already updated if (disp & DISP_MAIN) UpdateMainDisplay(); if (disp & DISP_MENUE) UpdateMenuDisplay(); - _ASSERT((disp & DISP_ANNUN) == 0); // annunciators already updated disp = 0; // display updated return; } @@ -599,7 +598,7 @@ loop: UpdateMainDisplay(); UpdateMenuDisplay(); RefreshDisp0(); // CdB for HP: add apples display management - UpdateAnnunciators(); + UpdateAnnunciators(0x3F); // init speed reference dwOldCyc = (DWORD) (Chipset.cycles & 0xFFFFFFFF); QueryPerformanceCounter(&lDummyInt); diff --git a/app/src/main/cpp/core/external.c b/app/src/main/cpp/core/external.c deleted file mode 100644 index 9193d19..0000000 --- a/app/src/main/cpp/core/external.c +++ /dev/null @@ -1,100 +0,0 @@ -/* - * external.c - * - * This file is part of Emu48 - * - * Copyright (C) 1995 Sebastien Carlier - * Copyright (C) 2005 Christoph Gießelink - * - */ -#include "pch.h" -#include "Emu48.h" -#include "ops.h" - -//| 38G | 39G | 40G | 48SX | 48GX | 49G | Name -//#F0E4F #80F0F #80F0F #706D2 #80850 #80F0F =SFLAG53_56 - -// memory address for flags -53 to -56 - // CdB for HP: add apples beep management -#define SFLAG53_56 ( (cCurrentRomType=='6') \ - ? 0xE0E4F \ - : ( (cCurrentRomType=='A') \ - ? 0xF0E4F \ - : ( (cCurrentRomType!='E' && cCurrentRomType!='X' && cCurrentRomType!='P' && cCurrentRomType!='2' && cCurrentRomType!='Q') \ - ? ( (cCurrentRomType=='S') \ - ? 0x706D2 \ - : 0x80850 \ - ) \ - : 0x80F0F \ - ) \ - ) \ - ) - -VOID External(CHIPSET* w) // Beep patch -{ - BYTE fbeep; - DWORD freq,dur; - - freq = Npack(w->D,5); // frequency in Hz - dur = Npack(w->C,5); // duration in ms - Nread(&fbeep,SFLAG53_56,1); // fetch system flags -53 to -56 - - w->carry = TRUE; // setting of no beep - if (!(fbeep & 0x8) && freq) // bit -56 clear and frequency > 0 Hz - { - if (freq > 4400) freq = 4400; // high limit of HP (SX) - - SoundBeep(freq,dur); // beeping - - // estimate cpu cycles for beeping time (2MHz / 4MHz) - w->cycles += dur * ((cCurrentRomType=='S') ? 2000 : 4000); - - // original routine return with... - w->P = 0; // P=0 - w->intk = TRUE; // INTON - w->carry = FALSE; // RTNCC - } - w->pc = rstkpop(); - return; -} - -VOID RCKBp(CHIPSET* w) // ROM Check Beep patch -{ - DWORD dw2F,dwCpuFreq; - DWORD freq,dur; - BYTE f,d; - - f = w->C[1]; // f = freq ctl - d = w->C[0]; // d = duration ctl - - if (cCurrentRomType == 'S') // Clarke chip with 48S ROM - { - // CPU strobe frequency @ RATE 14 = 1.97MHz - dwCpuFreq = ((14 + 1) * 524288) >> 2; - - dw2F = f * 126 + 262; // F=f*63+131 - } - else // York chip with 48G and later ROM - { - // CPU strobe frequency @ RATE 27 = 3.67MHz - // CPU strobe frequency @ RATE 29 = 3.93MHz - dwCpuFreq = ((27 + 1) * 524288) >> 2; - - dw2F = f * 180 + 367; // F=f*90+183.5 - } - - freq = dwCpuFreq / dw2F; - dur = (dw2F * (256 - 16 * d)) * 1000 / 2 / dwCpuFreq; - - if (freq > 4400) freq = 4400; // high limit of HP - - SoundBeep(freq,dur); // beeping - - // estimate cpu cycles for beeping time (2MHz / 4MHz) - w->cycles += dur * ((cCurrentRomType=='S') ? 2000 : 4000); - - w->P = 0; // P=0 - w->carry = FALSE; // RTNCC - w->pc = rstkpop(); - return; -} diff --git a/app/src/main/cpp/core/fetch.c b/app/src/main/cpp/core/fetch.c index f67c362..1ac9c0c 100644 --- a/app/src/main/cpp/core/fetch.c +++ b/app/src/main/cpp/core/fetch.c @@ -321,7 +321,7 @@ static JMPTAB o8A_[] = static JMPTAB o81B_[] = { (LPCVOID) o_invalid4, F, - (LPCVOID) o81B1, F, // normally o_invalid4, beep patch, Apple: LOOP + (LPCVOID) o81B1, F, // normally o_invalid4, Apple: LOOP (LPCVOID) o81B2, F, (LPCVOID) o81B3, F, (LPCVOID) o81B4, F, diff --git a/app/src/main/cpp/core/files.c b/app/src/main/cpp/core/files.c index 8b98519..5861ef3 100644 --- a/app/src/main/cpp/core/files.c +++ b/app/src/main/cpp/core/files.c @@ -1017,8 +1017,16 @@ BOOL OpenDocument(LPCTSTR szFilename) case 0xFE: // Win48 2.1 / Emu4x 0.99.x format // read length of KML script name ReadFile(hFile,&nLength,sizeof(nLength),&lBytesRead,NULL); + // KML script name too long for file buffer - if (nLength >= ARRAYSIZEOF(szCurrentKml)) goto read_err; + if (nLength >= ARRAYSIZEOF(szCurrentKml)) + { + // skip heading KML script name characters until remainder fits into file buffer + UINT nSkip = nLength - (ARRAYSIZEOF(szCurrentKml) - 1); + SetFilePointer(hFile, nSkip, NULL, FILE_CURRENT); + + nLength = ARRAYSIZEOF(szCurrentKml) - 1; + } #if defined _UNICODE { LPSTR szTmp = (LPSTR) malloc(nLength); @@ -2575,7 +2583,7 @@ static BOOL LabColorCmp(DWORD dwColor1,DWORD dwColor2,DWORD dwTol) nDiffCol = (INT) (dwColor1 & 0xFF) - (INT) (dwColor2 & 0xFF); dwDiff += (DWORD) (nDiffCol * nDiffCol); dwTol *= dwTol; - + return dwDiff > dwTol; // FALSE = colors match } diff --git a/app/src/main/cpp/core/kml.c b/app/src/main/cpp/core/kml.c index 52a8479..b8c3c5a 100644 --- a/app/src/main/cpp/core/kml.c +++ b/app/src/main/cpp/core/kml.c @@ -2630,9 +2630,8 @@ BOOL InitKML(LPCTSTR szFilename, BOOL bNoLog) } if (CheckForBeepPatch()) // check if ROM contain beep patches { - AddToLog(_T("Warning, ROM beep patch detected. Remove beep patches please.")); - bNoLog = FALSE; - bAlwaysDisplayLog = TRUE; + AddToLog(_T("Error, ROM beep patch detected. Remove beep patches please.")); + goto quit; } ResizeMainBitmap(nScaleMul,nScaleDiv); // resize main picture diff --git a/app/src/main/cpp/core/lodepng.c b/app/src/main/cpp/core/lodepng.c index ae71df3..ddf11ca 100644 --- a/app/src/main/cpp/core/lodepng.c +++ b/app/src/main/cpp/core/lodepng.c @@ -1,7 +1,7 @@ /* -LodePNG version 20190914 +LodePNG version 20200306 -Copyright (c) 2005-2019 Lode Vandevenne +Copyright (c) 2005-2020 Lode Vandevenne This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages @@ -44,7 +44,7 @@ Rename this file to lodepng.cpp to use it for C++, or to lodepng.c to use it for #pragma warning( disable : 4996 ) /*VS does not like fopen, but fopen_s is not standard C so unusable here*/ #endif /*_MSC_VER */ -const char* LODEPNG_VERSION_STRING = "20190914"; +const char* LODEPNG_VERSION_STRING = "20200306"; /* This source file is built up in the following large parts. The code sections @@ -78,6 +78,7 @@ static void* lodepng_malloc(size_t size) { return malloc(size); } +/* NOTE: when realloc returns NULL, it leaves the original memory untouched */ static void* lodepng_realloc(void* ptr, size_t new_size) { #ifdef LODEPNG_MAX_ALLOC if(new_size > LODEPNG_MAX_ALLOC) return 0; @@ -104,14 +105,15 @@ void lodepng_free(void* ptr); #endif /* restrict is not available in C90, but use it when supported by the compiler */ -#if (defined(__GNUC__) && defined(__GNUC_MINOR__) && (__GNUC__ >= 3) && (__GNUC_MINOR__ >= 1)) ||\ - (defined(_MSC_VER) && (_MSC_VER >= 1400)) || (defined(__WATCOMC__) && (__WATCOMC__ >= 1250)) +#if (defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))) ||\ + (defined(_MSC_VER) && (_MSC_VER >= 1400)) || \ + (defined(__WATCOMC__) && (__WATCOMC__ >= 1250) && !defined(__cplusplus)) #define LODEPNG_RESTRICT __restrict #else #define LODEPNG_RESTRICT /* not available */ #endif -/* Replacements for C library functions memcpy and strlen, to support those platforms +/* Replacements for C library functions such as memcpy and strlen, to support platforms where a full C library is not available. The compiler can recognize them and compile to something as fast. */ @@ -121,11 +123,17 @@ static void lodepng_memcpy(void* LODEPNG_RESTRICT dst, for(i = 0; i < size; i++) ((char*)dst)[i] = ((const char*)src)[i]; } +static void lodepng_memset(void* LODEPNG_RESTRICT dst, + int value, size_t num) { + size_t i; + for(i = 0; i < num; i++) ((char*)dst)[i] = (char)value; +} + /* does not check memory out of bounds, do not use on untrusted data */ static size_t lodepng_strlen(const char* a) { const char* orig = a; /* avoid warning about unused function in case of disabled COMPILE... macros */ - (void)lodepng_strlen; + (void)(&lodepng_strlen); while(*a) a++; return (size_t)(a - orig); } @@ -134,6 +142,14 @@ static size_t lodepng_strlen(const char* a) { #define LODEPNG_MIN(a, b) (((a) < (b)) ? (a) : (b)) #define LODEPNG_ABS(x) ((x) < 0 ? -(x) : (x)) +#if defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_DECODER) +/* Safely check if adding two integers will overflow (no undefined +behavior, compiler removing the code, etc...) and output result. */ +static int lodepng_addofl(size_t a, size_t b, size_t* result) { + *result = a + b; /* Unsigned addition is well defined and safe in C90 */ + return *result < a; +} +#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_DECODER)*/ #ifdef LODEPNG_COMPILE_DECODER /* Safely check if multiplying two integers will overflow (no undefined @@ -143,13 +159,6 @@ static int lodepng_mulofl(size_t a, size_t b, size_t* result) { return (a != 0 && *result / a != b); } -/* Safely check if adding two integers will overflow (no undefined -behavior, compiler removing the code, etc...) and output result. */ -static int lodepng_addofl(size_t a, size_t b, size_t* result) { - *result = a + b; /* Unsigned addition is well defined and safe in C90 */ - return *result < a; -} - #ifdef LODEPNG_COMPILE_ZLIB /* Safely check if a + b > c, even if overflow could happen. */ static int lodepng_gtofl(size_t a, size_t b, size_t c) { @@ -166,7 +175,7 @@ Often in case of an error a value is assigned to a variable and then it breaks out of a loop (to go to the cleanup phase of a function). This macro does that. It makes the error handling code shorter and more readable. -Example: if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83); +Example: if(!uivector_resize(&lz77_encoded, datasize)) ERROR_BREAK(83); */ #define CERROR_BREAK(errorvar, code){\ errorvar = code;\ @@ -219,9 +228,10 @@ static void uivector_cleanup(void* p) { } /*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_reserve(uivector* p, size_t allocsize) { +static unsigned uivector_resize(uivector* p, size_t size) { + size_t allocsize = size * sizeof(unsigned); if(allocsize > p->allocsize) { - size_t newsize = (allocsize > p->allocsize * 2u) ? allocsize : ((allocsize * 3u) >> 1u); + size_t newsize = allocsize + (p->allocsize >> 1u); void* data = lodepng_realloc(p->data, newsize); if(data) { p->allocsize = newsize; @@ -229,24 +239,10 @@ static unsigned uivector_reserve(uivector* p, size_t allocsize) { } else return 0; /*error: not enough memory*/ } - return 1; -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned uivector_resize(uivector* p, size_t size) { - if(!uivector_reserve(p, size * sizeof(unsigned))) return 0; p->size = size; return 1; /*success*/ } -/*resize and give all new elements the value*/ -static unsigned uivector_resizev(uivector* p, size_t size, unsigned value) { - size_t oldsize = p->size, i; - if(!uivector_resize(p, size)) return 0; - for(i = oldsize; i < size; ++i) p->data[i] = value; - return 1; -} - static void uivector_init(uivector* p) { p->data = NULL; p->size = p->allocsize = 0; @@ -271,9 +267,9 @@ typedef struct ucvector { } ucvector; /*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_reserve(ucvector* p, size_t allocsize) { - if(allocsize > p->allocsize) { - size_t newsize = (allocsize > p->allocsize * 2u) ? allocsize : ((allocsize * 3u) >> 1u); +static unsigned ucvector_resize(ucvector* p, size_t size) { + if(size > p->allocsize) { + size_t newsize = size + (p->allocsize >> 1u); void* data = lodepng_realloc(p->data, newsize); if(data) { p->allocsize = newsize; @@ -281,49 +277,17 @@ static unsigned ucvector_reserve(ucvector* p, size_t allocsize) { } else return 0; /*error: not enough memory*/ } - return 1; -} - -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_resize(ucvector* p, size_t size) { - if(!ucvector_reserve(p, size * sizeof(unsigned char))) return 0; p->size = size; return 1; /*success*/ } -#ifdef LODEPNG_COMPILE_PNG - -static void ucvector_cleanup(void* p) { - ((ucvector*)p)->size = ((ucvector*)p)->allocsize = 0; - lodepng_free(((ucvector*)p)->data); - ((ucvector*)p)->data = NULL; +static ucvector ucvector_init(unsigned char* buffer, size_t size) { + ucvector v; + v.data = buffer; + v.allocsize = v.size = size; + return v; } -static void ucvector_init(ucvector* p) { - p->data = NULL; - p->size = p->allocsize = 0; -} -#endif /*LODEPNG_COMPILE_PNG*/ - -#ifdef LODEPNG_COMPILE_ZLIB -/*you can both convert from vector to buffer&size and vice versa. If you use -init_buffer to take over a buffer and size, it is not needed to use cleanup*/ -static void ucvector_init_buffer(ucvector* p, unsigned char* buffer, size_t size) { - p->data = buffer; - p->allocsize = p->size = size; -} -#endif /*LODEPNG_COMPILE_ZLIB*/ - -#if (defined(LODEPNG_COMPILE_PNG) && defined(LODEPNG_COMPILE_ANCILLARY_CHUNKS)) || defined(LODEPNG_COMPILE_ENCODER) -/*returns 1 if success, 0 if failure ==> nothing done*/ -static unsigned ucvector_push_back(ucvector* p, unsigned char c) { - if(!ucvector_resize(p, p->size + 1)) return 0; - p->data[p->size - 1] = c; - return 1; -} -#endif /*defined(LODEPNG_COMPILE_PNG) || defined(LODEPNG_COMPILE_ENCODER)*/ - - /* ////////////////////////////////////////////////////////////////////////// */ #ifdef LODEPNG_COMPILE_PNG @@ -335,19 +299,19 @@ static void string_cleanup(char** out) { *out = NULL; } -/* dynamically allocates a new string with a copy of the null terminated input text */ -static char* alloc_string(const char* in) { - size_t insize = lodepng_strlen(in); +static char* alloc_string_sized(const char* in, size_t insize) { char* out = (char*)lodepng_malloc(insize + 1); if(out) { - size_t i; - for(i = 0; i != insize; ++i) { - out[i] = in[i]; - } - out[i] = 0; + lodepng_memcpy(out, in, insize); + out[insize] = 0; } return out; } + +/* dynamically allocates a new string with a copy of the null terminated input text */ +static char* alloc_string(const char* in) { + return alloc_string_sized(in, lodepng_strlen(in)); +} #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ #endif /*LODEPNG_COMPILE_PNG*/ @@ -406,13 +370,13 @@ static unsigned lodepng_buffer_file(unsigned char* out, size_t size, const char* readsize = fread(out, 1, size, file); fclose(file); - if (readsize != size) return 78; + if(readsize != size) return 78; return 0; } unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename) { long size = lodepng_filesize(filename); - if (size < 0) return 78; + if(size < 0) return 78; *outsize = (size_t)size; *out = (unsigned char*)lodepng_malloc((size_t)size); @@ -444,18 +408,21 @@ unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const typedef struct { ucvector* data; - size_t bp; + unsigned char bp; /*ok to overflow, indicates bit pos inside byte*/ } LodePNGBitWriter; -void LodePNGBitWriter_init(LodePNGBitWriter* writer, ucvector* data) { +static void LodePNGBitWriter_init(LodePNGBitWriter* writer, ucvector* data) { writer->data = data; writer->bp = 0; } /*TODO: this ignores potential out of memory errors*/ -#define WRITEBIT(/*size_t**/ writer, /*unsigned char*/ bit){\ +#define WRITEBIT(writer, bit){\ /* append new byte */\ - if(((writer->bp) & 7u) == 0) ucvector_push_back(writer->data, (unsigned char)0);\ + if(((writer->bp) & 7u) == 0) {\ + if(!ucvector_resize(writer->data, writer->data->size + 1)) return;\ + writer->data->data[writer->data->size - 1] = 0;\ + }\ (writer->data->data[writer->data->size - 1]) |= (bit << ((writer->bp) & 7u));\ ++writer->bp;\ } @@ -465,7 +432,7 @@ static void writeBits(LodePNGBitWriter* writer, unsigned value, size_t nbits) { if(nbits == 1) { /* compiler should statically compile this case if nbits == 1 */ WRITEBIT(writer, value); } else { - /* TODO: increase output size nly once here rather than in each WRITEBIT */ + /* TODO: increase output size only once here rather than in each WRITEBIT */ size_t i; for(i = 0; i != nbits; ++i) { WRITEBIT(writer, (unsigned char)((value >> i) & 1)); @@ -527,14 +494,14 @@ static unsigned ensureBits9(LodePNGBitReader* reader, size_t nbits) { size_t start = reader->bp >> 3u; size_t size = reader->size; if(start + 1u < size) { - reader->buffer = (unsigned)(reader->data[start + 0]) | (unsigned)(reader->data[start + 1] << 8u); + reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u); reader->buffer >>= (reader->bp & 7u); return 1; } else { reader->buffer = 0; if(start + 0u < size) reader->buffer |= reader->data[start + 0]; reader->buffer >>= (reader->bp & 7u); - return reader->bp + nbits < reader->bitsize; + return reader->bp + nbits <= reader->bitsize; } } @@ -543,16 +510,16 @@ static unsigned ensureBits17(LodePNGBitReader* reader, size_t nbits) { size_t start = reader->bp >> 3u; size_t size = reader->size; if(start + 2u < size) { - reader->buffer = (unsigned)(reader->data[start + 0]) | (unsigned)(reader->data[start + 1] << 8u) | - (unsigned)(reader->data[start + 2] << 16u); + reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | + ((unsigned)reader->data[start + 2] << 16u); reader->buffer >>= (reader->bp & 7u); return 1; } else { reader->buffer = 0; if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= (unsigned)(reader->data[start + 1] << 8u); + if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); reader->buffer >>= (reader->bp & 7u); - return reader->bp + nbits < reader->bitsize; + return reader->bp + nbits <= reader->bitsize; } } @@ -561,17 +528,17 @@ static LODEPNG_INLINE unsigned ensureBits25(LodePNGBitReader* reader, size_t nbi size_t start = reader->bp >> 3u; size_t size = reader->size; if(start + 3u < size) { - reader->buffer = (unsigned)(reader->data[start + 0]) | (unsigned)(reader->data[start + 1] << 8u) | - (unsigned)(reader->data[start + 2] << 16u) | (unsigned)(reader->data[start + 3] << 24u); + reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | + ((unsigned)reader->data[start + 2] << 16u) | ((unsigned)reader->data[start + 3] << 24u); reader->buffer >>= (reader->bp & 7u); return 1; } else { reader->buffer = 0; if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= (unsigned)(reader->data[start + 1] << 8u); - if(start + 2u < size) reader->buffer |= (unsigned)(reader->data[start + 2] << 16u); + if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); + if(start + 2u < size) reader->buffer |= ((unsigned)reader->data[start + 2] << 16u); reader->buffer >>= (reader->bp & 7u); - return reader->bp + nbits < reader->bitsize; + return reader->bp + nbits <= reader->bitsize; } } @@ -580,24 +547,25 @@ static LODEPNG_INLINE unsigned ensureBits32(LodePNGBitReader* reader, size_t nbi size_t start = reader->bp >> 3u; size_t size = reader->size; if(start + 4u < size) { - reader->buffer = (unsigned)(reader->data[start + 0]) | (unsigned)(reader->data[start + 1] << 8u) | - (unsigned)(reader->data[start + 2] << 16u) | (unsigned)(reader->data[start + 3] << 24u); + reader->buffer = (unsigned)reader->data[start + 0] | ((unsigned)reader->data[start + 1] << 8u) | + ((unsigned)reader->data[start + 2] << 16u) | ((unsigned)reader->data[start + 3] << 24u); reader->buffer >>= (reader->bp & 7u); - reader->buffer |= ((unsigned)(reader->data[start + 4] << 24u) << (7u - (reader->bp & 7u))); + reader->buffer |= (((unsigned)reader->data[start + 4] << 24u) << (8u - (reader->bp & 7u))); return 1; } else { reader->buffer = 0; if(start + 0u < size) reader->buffer |= reader->data[start + 0]; - if(start + 1u < size) reader->buffer |= (unsigned)(reader->data[start + 1] << 8u); - if(start + 2u < size) reader->buffer |= (unsigned)(reader->data[start + 2] << 16u); - if(start + 3u < size) reader->buffer |= (unsigned)(reader->data[start + 3] << 24u); + if(start + 1u < size) reader->buffer |= ((unsigned)reader->data[start + 1] << 8u); + if(start + 2u < size) reader->buffer |= ((unsigned)reader->data[start + 2] << 16u); + if(start + 3u < size) reader->buffer |= ((unsigned)reader->data[start + 3] << 24u); reader->buffer >>= (reader->bp & 7u); - return reader->bp + nbits < reader->bitsize; + return reader->bp + nbits <= reader->bitsize; } } -/* Get bits without advancing the bit pointer. Must have enough bits available with ensureBits */ +/* Get bits without advancing the bit pointer. Must have enough bits available with ensureBits. Max nbits is 31. */ static unsigned peekBits(LodePNGBitReader* reader, size_t nbits) { + /* The shift allows nbits to be only up to 31. */ return reader->buffer & ((1u << nbits) - 1u); } @@ -613,6 +581,26 @@ static unsigned readBits(LodePNGBitReader* reader, size_t nbits) { advanceBits(reader, nbits); return result; } + +/* Public for testing only. steps and result must have numsteps values. */ +unsigned lode_png_test_bitreader(const unsigned char* data, size_t size, + size_t numsteps, const size_t* steps, unsigned* result) { + size_t i; + LodePNGBitReader reader; + unsigned error = LodePNGBitReader_init(&reader, data, size); + if(error) return 0; + for(i = 0; i < numsteps; i++) { + size_t step = steps[i]; + unsigned ok; + if(step > 25) ok = ensureBits32(&reader, step); + else if(step > 17) ok = ensureBits25(&reader, step); + else if(step > 9) ok = ensureBits17(&reader, step); + else ok = ensureBits9(&reader, step); + if(!ok) return 0; + result[i] = readBits(&reader, step); + } + return 1; +} #endif /*LODEPNG_COMPILE_DECODER*/ static unsigned reverseBits(unsigned bits, unsigned num) { @@ -655,8 +643,8 @@ static const unsigned DISTANCEEXTRA[30] = {0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13}; -/*the order in which "code length alphabet code lengths" are stored, out of this -the huffman tree of the dynamic huffman tree lengths is generated*/ +/*the order in which "code length alphabet code lengths" are stored as specified by deflate, out of this the huffman +tree of the dynamic huffman tree lengths is generated*/ static const unsigned CLCL_ORDER[NUM_CODE_LENGTH_CODES] = {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; @@ -693,16 +681,20 @@ static void HuffmanTree_cleanup(HuffmanTree* tree) { /* values 8u and 9u work the fastest */ #define FIRSTBITS 9u +/* a symbol value too big to represent any valid symbol, to indicate reading disallowed huffman bits combination, +which is possible in case of only 0 or 1 present symbols. */ +#define INVALIDSYMBOL 65535u + /* make table for huffman decoding */ static unsigned HuffmanTree_makeTable(HuffmanTree* tree) { static const unsigned headsize = 1u << FIRSTBITS; /*size of the first table*/ static const unsigned mask = (1u << FIRSTBITS) /*headsize*/ - 1u; - unsigned i, pointer, size; /*total table size*/ + unsigned i, numpresent, pointer, size; /*total table size*/ unsigned* maxlens = (unsigned*)lodepng_malloc(headsize * sizeof(unsigned)); if(!maxlens) return 83; /*alloc fail*/ /* compute maxlens: max total bit length of symbols sharing prefix in the first table*/ - for(i = 0; i < headsize; ++i) maxlens[i] = 0; + lodepng_memset(maxlens, 0, headsize * sizeof(*maxlens)); for(i = 0; i < tree->numcodes; i++) { unsigned symbol = tree->codes[i]; unsigned l = tree->lengths[i]; @@ -740,14 +732,16 @@ static unsigned HuffmanTree_makeTable(HuffmanTree* tree) { lodepng_free(maxlens); /*fill in the first table for short symbols, or secondary table for long symbols*/ + numpresent = 0; for(i = 0; i < tree->numcodes; ++i) { unsigned l = tree->lengths[i]; unsigned symbol = tree->codes[i]; /*the huffman bit pattern. i itself is the value.*/ /*reverse bits, because the huffman bits are given in MSB first order but the bit reader reads LSB first*/ unsigned reverse = reverseBits(symbol, l); - if(l == 0) { - continue; - } else if(l <= FIRSTBITS) { + if(l == 0) continue; + numpresent++; + + if(l <= FIRSTBITS) { /*short symbol, fully in first table, replicated num times if l < FIRSTBITS*/ unsigned num = 1u << (FIRSTBITS - l); unsigned j; @@ -778,12 +772,30 @@ static unsigned HuffmanTree_makeTable(HuffmanTree* tree) { } } - /* A good huffman tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. - If that is not the case (due to too long length codes), the table will not - have been fully used, and this is an error (not all bit combinations can be - decoded): an oversubscribed huffman tree, indicated by error 55. */ - for(i = 0; i < size; ++i) { - if(tree->table_len[i] == 16) return 55; + if(numpresent < 2) { + /* In case of exactly 1 symbol, in theory the huffman symbol needs 0 bits, + but deflate uses 1 bit instead. In case of 0 symbols, no symbols can + appear at all, but such huffman tree could still exist (e.g. if distance + codes are never used). In both cases, not all symbols of the table will be + filled in. Fill them in with an invalid symbol value so returning them from + huffmanDecodeSymbol will cause error. */ + for(i = 0; i < size; ++i) { + if(tree->table_len[i] == 16) { + /* As length, use a value smaller than FIRSTBITS for the head table, + and a value larger than FIRSTBITS for the secondary table, to ensure + valid behavior for advanceBits when reading this symbol. */ + tree->table_len[i] = (i < headsize) ? 1 : (FIRSTBITS + 1); + tree->table_value[i] = INVALIDSYMBOL; + } + } + } else { + /* A good huffman tree has N * 2 - 1 nodes, of which N - 1 are internal nodes. + If that is not the case (due to too long length codes), the table will not + have been fully used, and this is an error (not all bit combinations can be + decoded): an oversubscribed huffman tree, indicated by error 55. */ + for(i = 0; i < size; ++i) { + if(tree->table_len[i] == 16) return 55; + } } return 0; @@ -811,7 +823,7 @@ static unsigned HuffmanTree_makeFromLengths2(HuffmanTree* tree) { for(bits = 0; bits != tree->numcodes; ++bits) ++blcount[tree->lengths[bits]]; /*step 2: generate the nextcode values*/ for(bits = 1; bits <= tree->maxbitlen; ++bits) { - nextcode[bits] = (nextcode[bits - 1] + blcount[bits - 1]) << 1; + nextcode[bits] = (nextcode[bits - 1] + blcount[bits - 1]) << 1u; } /*step 3: generate all the codes*/ for(n = 0; n != tree->numcodes; ++n) { @@ -972,7 +984,7 @@ unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequen } } - for(i = 0; i != numcodes; ++i) lengths[i] = 0; + lodepng_memset(lengths, 0, numcodes * sizeof(*lengths)); /*ensure at least two present symbols. There should be at least one symbol according to RFC 1951 section 3.2.7. Some decoders incorrectly require two. To @@ -1032,28 +1044,17 @@ unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequen /*Create the Huffman tree given the symbol frequencies*/ static unsigned HuffmanTree_makeFromFrequencies(HuffmanTree* tree, const unsigned* frequencies, size_t mincodes, size_t numcodes, unsigned maxbitlen) { - size_t i; unsigned error = 0; while(!frequencies[numcodes - 1] && numcodes > mincodes) --numcodes; /*trim zeroes*/ + tree->lengths = (unsigned*)lodepng_malloc(numcodes * sizeof(unsigned)); + if(!tree->lengths) return 83; /*alloc fail*/ tree->maxbitlen = maxbitlen; tree->numcodes = (unsigned)numcodes; /*number of symbols*/ - tree->lengths = (unsigned*)lodepng_realloc(tree->lengths, numcodes * sizeof(unsigned)); - if(!tree->lengths) return 83; /*alloc fail*/ - /*initialize all lengths to 0*/ - for(i = 0; i < numcodes; i++) tree->lengths[i] = 0; error = lodepng_huffman_code_lengths(tree->lengths, frequencies, numcodes, maxbitlen); if(!error) error = HuffmanTree_makeFromLengths2(tree); return error; } - -static unsigned HuffmanTree_getCode(const HuffmanTree* tree, unsigned index) { - return tree->codes[index]; -} - -static unsigned HuffmanTree_getLength(const HuffmanTree* tree, unsigned index) { - return tree->lengths[index]; -} #endif /*LODEPNG_COMPILE_ENCODER*/ /*get the literal and length code tree of a deflated block with fixed tree, as per the deflate specification*/ @@ -1116,11 +1117,12 @@ static unsigned huffmanDecodeSymbol(LodePNGBitReader* reader, const HuffmanTree* /* / Inflator (Decompressor) / */ /* ////////////////////////////////////////////////////////////////////////// */ -/*get the tree of a deflated block with fixed tree, as specified in the deflate specification*/ -static void getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) { - /*TODO: check for out of memory errors*/ - generateFixedLitLenTree(tree_ll); - generateFixedDistanceTree(tree_d); +/*get the tree of a deflated block with fixed tree, as specified in the deflate specification +Returns error code.*/ +static unsigned getTreeInflateFixed(HuffmanTree* tree_ll, HuffmanTree* tree_d) { + unsigned error = generateFixedLitLenTree(tree_ll); + if(error) return error; + return generateFixedDistanceTree(tree_d); } /*get the tree of a deflated block with dynamic tree, the tree itself is also Huffman compressed with a known tree*/ @@ -1171,8 +1173,8 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, bitlen_ll = (unsigned*)lodepng_malloc(NUM_DEFLATE_CODE_SYMBOLS * sizeof(unsigned)); bitlen_d = (unsigned*)lodepng_malloc(NUM_DISTANCE_SYMBOLS * sizeof(unsigned)); if(!bitlen_ll || !bitlen_d) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i != NUM_DEFLATE_CODE_SYMBOLS; ++i) bitlen_ll[i] = 0; - for(i = 0; i != NUM_DISTANCE_SYMBOLS; ++i) bitlen_d[i] = 0; + lodepng_memset(bitlen_ll, 0, NUM_DEFLATE_CODE_SYMBOLS * sizeof(*bitlen_ll)); + lodepng_memset(bitlen_d, 0, NUM_DISTANCE_SYMBOLS * sizeof(*bitlen_d)); /*i is the current symbol we're reading in the part that contains the code lengths of lit/len and dist codes*/ i = 0; @@ -1225,8 +1227,8 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, else bitlen_d[i - HLIT] = 0; ++i; } - } else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ { - ERROR_BREAK(16); /*nonexistent code, this can never happen*/ + } else /*if(code == INVALIDSYMBOL)*/ { + ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ } /*check if any of the ensureBits above went out of bounds*/ if(reader->bp > reader->bitsize) { @@ -1257,7 +1259,7 @@ static unsigned getTreeInflateDynamic(HuffmanTree* tree_ll, HuffmanTree* tree_d, } /*inflate a block with dynamic of fixed Huffman tree. btype must be 1 or 2.*/ -static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader* reader, +static unsigned inflateHuffmanBlock(ucvector* out, LodePNGBitReader* reader, unsigned btype) { unsigned error = 0; HuffmanTree tree_ll; /*the huffman tree for literal and length codes*/ @@ -1266,7 +1268,7 @@ static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader HuffmanTree_init(&tree_ll); HuffmanTree_init(&tree_d); - if(btype == 1) getTreeInflateFixed(&tree_ll, &tree_d); + if(btype == 1) error = getTreeInflateFixed(&tree_ll, &tree_d); else /*if(btype == 2)*/ error = getTreeInflateDynamic(&tree_ll, &tree_d, reader); while(!error) /*decode all symbols until end reached, breaks at end code*/ { @@ -1275,10 +1277,8 @@ static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader ensureBits25(reader, 20); /* up to 15 for the huffman symbol, up to 5 for the length extra bits */ code_ll = huffmanDecodeSymbol(reader, &tree_ll); if(code_ll <= 255) /*literal symbol*/ { - /*ucvector_push_back would do the same, but for some reason the two lines below run 10% faster*/ - if(!ucvector_resize(out, (*pos) + 1)) ERROR_BREAK(83 /*alloc fail*/); - out->data[*pos] = (unsigned char)code_ll; - ++(*pos); + if(!ucvector_resize(out, out->size + 1)) ERROR_BREAK(83 /*alloc fail*/); + out->data[out->size - 1] = (unsigned char)code_ll; } else if(code_ll >= FIRST_LENGTH_CODE_INDEX && code_ll <= LAST_LENGTH_CODE_INDEX) /*length code*/ { unsigned code_d, distance; unsigned numextrabits_l, numextrabits_d; /*extra bits for length and distance*/ @@ -1298,12 +1298,10 @@ static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader ensureBits32(reader, 28); /* up to 15 for the huffman symbol, up to 13 for the extra bits */ code_d = huffmanDecodeSymbol(reader, &tree_d); if(code_d > 29) { - if(code_d == (unsigned)(-1)) /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ { - /*return error code 10 or 11 depending on the situation that happened in huffmanDecodeSymbol - (10=no endcode, 11=wrong jump outside of tree)*/ - ERROR_BREAK((reader->bp > reader->bitsize) ? 10 : 11); - } else { + if(code_d <= 31) { ERROR_BREAK(18); /*error: invalid distance code (30-31 are never used)*/ + } else /* if(code_d == INVALIDSYMBOL) */{ + ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ } } distance = DISTANCEBASE[code_d]; @@ -1316,26 +1314,25 @@ static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader } /*part 5: fill in all the out[n] values based on the length and dist*/ - start = (*pos); + start = out->size; if(distance > start) ERROR_BREAK(52); /*too long backward distance*/ backward = start - distance; - if(!ucvector_resize(out, (*pos) + length)) ERROR_BREAK(83 /*alloc fail*/); - if (distance < length) { + if(!ucvector_resize(out, out->size + length)) ERROR_BREAK(83 /*alloc fail*/); + if(distance < length) { size_t forward; - lodepng_memcpy(out->data + *pos, out->data + backward, distance); - *pos += distance; + lodepng_memcpy(out->data + start, out->data + backward, distance); + start += distance; for(forward = distance; forward < length; ++forward) { - out->data[(*pos)++] = out->data[backward++]; + out->data[start++] = out->data[backward++]; } } else { - lodepng_memcpy(out->data + *pos, out->data + backward, length); - *pos += length; + lodepng_memcpy(out->data + start, out->data + backward, length); } } else if(code_ll == 256) { break; /*end code, break the loop*/ - } else /*if(code == (unsigned)(-1))*/ /*huffmanDecodeSymbol returns (unsigned)(-1) in case of error*/ { - ERROR_BREAK(16) /* impossible */ + } else /*if(code_ll == INVALIDSYMBOL)*/ { + ERROR_BREAK(16); /*error: tried to read disallowed huffman symbol*/ } /*check if any of the ensureBits above went out of bounds*/ if(reader->bp > reader->bitsize) { @@ -1352,8 +1349,8 @@ static unsigned inflateHuffmanBlock(ucvector* out, size_t* pos, LodePNGBitReader return error; } -static unsigned inflateNoCompression(ucvector* out, size_t* pos, - LodePNGBitReader* reader, const LodePNGDecompressSettings* settings) { +static unsigned inflateNoCompression(ucvector* out, LodePNGBitReader* reader, + const LodePNGDecompressSettings* settings) { size_t bytepos; size_t size = reader->size; unsigned LEN, NLEN, error = 0; @@ -1363,21 +1360,20 @@ static unsigned inflateNoCompression(ucvector* out, size_t* pos, /*read LEN (2 bytes) and NLEN (2 bytes)*/ if(bytepos + 4 >= size) return 52; /*error, bit pointer will jump past memory*/ - LEN = (unsigned)reader->data[bytepos] + (unsigned)(reader->data[bytepos + 1] << 8u); bytepos += 2; - NLEN = (unsigned)reader->data[bytepos] + (unsigned)(reader->data[bytepos + 1] << 8u); bytepos += 2; + LEN = (unsigned)reader->data[bytepos] + ((unsigned)reader->data[bytepos + 1] << 8u); bytepos += 2; + NLEN = (unsigned)reader->data[bytepos] + ((unsigned)reader->data[bytepos + 1] << 8u); bytepos += 2; /*check if 16-bit NLEN is really the one's complement of LEN*/ if(!settings->ignore_nlen && LEN + NLEN != 65535) { return 21; /*error: NLEN is not one's complement of LEN*/ } - if(!ucvector_resize(out, (*pos) + LEN)) return 83; /*alloc fail*/ + if(!ucvector_resize(out, out->size + LEN)) return 83; /*alloc fail*/ /*read the literal data: LEN bytes are now stored in the out buffer*/ if(bytepos + LEN > size) return 23; /*error: reading outside of in buffer*/ - lodepng_memcpy(out->data + *pos, reader->data + bytepos, LEN); - *pos += LEN; + lodepng_memcpy(out->data + out->size - LEN, reader->data + bytepos, LEN); bytepos += LEN; reader->bp = bytepos << 3u; @@ -1389,7 +1385,6 @@ static unsigned lodepng_inflatev(ucvector* out, const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { unsigned BFINAL = 0; - size_t pos = 0; /*byte position in the out buffer*/ LodePNGBitReader reader; unsigned error = LodePNGBitReader_init(&reader, in, insize); @@ -1402,8 +1397,8 @@ static unsigned lodepng_inflatev(ucvector* out, BTYPE = readBits(&reader, 2); if(BTYPE == 3) return 20; /*error: invalid BTYPE*/ - else if(BTYPE == 0) error = inflateNoCompression(out, &pos, &reader, settings); /*no compression*/ - else error = inflateHuffmanBlock(out, &pos, &reader, BTYPE); /*compression, BTYPE 01 or 10*/ + else if(BTYPE == 0) error = inflateNoCompression(out, &reader, settings); /*no compression*/ + else error = inflateHuffmanBlock(out, &reader, BTYPE); /*compression, BTYPE 01 or 10*/ if(error) return error; } @@ -1414,22 +1409,21 @@ static unsigned lodepng_inflatev(ucvector* out, unsigned lodepng_inflate(unsigned char** out, size_t* outsize, const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { - unsigned error; - ucvector v; - ucvector_init_buffer(&v, *out, *outsize); - error = lodepng_inflatev(&v, in, insize, settings); + ucvector v = ucvector_init(*out, *outsize); + unsigned error = lodepng_inflatev(&v, in, insize, settings); *out = v.data; *outsize = v.size; return error; } -static unsigned inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, +static unsigned inflatev(ucvector* out, const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { if(settings->custom_inflate) { - return settings->custom_inflate(out, outsize, in, insize, settings); + unsigned error = settings->custom_inflate(&out->data, &out->size, in, insize, settings); + out->allocsize = out->size; + return error; } else { - return lodepng_inflate(out, outsize, in, insize, settings); + return lodepng_inflatev(out, in, insize, settings); } } @@ -1441,7 +1435,7 @@ static unsigned inflate(unsigned char** out, size_t* outsize, /* / Deflator (Compressor) / */ /* ////////////////////////////////////////////////////////////////////////// */ -static const size_t MAX_SUPPORTED_DEFLATE_LENGTH = 258; +static const unsigned MAX_SUPPORTED_DEFLATE_LENGTH = 258; /*search the index in the array, that has the largest value smaller than or equal to the given value, given array must be sorted (if no value is smaller, it returns the size of the given array)*/ @@ -1452,7 +1446,7 @@ static size_t searchCodeIndex(const unsigned* array, size_t array_size, size_t v while(left <= right) { size_t mid = (left + right) >> 1; - if (array[mid] >= value) right = mid - 1; + if(array[mid] >= value) right = mid - 1; else left = mid + 1; } if(left >= array_size || array[left] > value) left--; @@ -1471,10 +1465,15 @@ static void addLengthDistance(uivector* values, size_t length, size_t distance) unsigned dist_code = (unsigned)searchCodeIndex(DISTANCEBASE, 30, distance); unsigned extra_distance = (unsigned)(distance - DISTANCEBASE[dist_code]); - uivector_push_back(values, length_code + FIRST_LENGTH_CODE_INDEX); - uivector_push_back(values, extra_length); - uivector_push_back(values, dist_code); - uivector_push_back(values, extra_distance); + size_t pos = values->size; + /*TODO: return error when this fails (out of memory)*/ + unsigned ok = uivector_resize(values, values->size + 4); + if(ok) { + values->data[pos + 0] = length_code + FIRST_LENGTH_CODE_INDEX; + values->data[pos + 1] = extra_length; + values->data[pos + 2] = dist_code; + values->data[pos + 3] = extra_distance; + } } /*3 bytes of data get encoded into two bytes. The hash cannot use more than 3 @@ -1539,14 +1538,14 @@ static unsigned getHash(const unsigned char* data, size_t size, size_t pos) { by zeroes due to the filters, a better hash does not have a significant effect on speed in traversing the chain, and causes more time spend on calculating the hash.*/ - result ^= (unsigned)(data[pos + 0] << 0u); - result ^= (unsigned)(data[pos + 1] << 4u); - result ^= (unsigned)(data[pos + 2] << 8u); + result ^= ((unsigned)data[pos + 0] << 0u); + result ^= ((unsigned)data[pos + 1] << 4u); + result ^= ((unsigned)data[pos + 2] << 8u); } else { size_t amount, i; if(pos >= size) return 0; amount = size - pos; - for(i = 0; i != amount; ++i) result ^= (unsigned)(data[pos + i] << (i * 8u)); + for(i = 0; i != amount; ++i) result ^= ((unsigned)data[pos + i] << (i * 8u)); } return result & HASH_BIT_MASK; } @@ -1588,7 +1587,7 @@ static unsigned encodeLZ77(uivector* out, Hash* hash, unsigned i, error = 0; /*for large window lengths, assume the user wants no compression loss. Otherwise, max hash chain length speedup.*/ unsigned maxchainlength = windowsize >= 8192 ? windowsize : windowsize / 8u; - unsigned maxlazymatch = windowsize >= 8192 ? (unsigned)MAX_SUPPORTED_DEFLATE_LENGTH : 64; + unsigned maxlazymatch = windowsize >= 8192 ? MAX_SUPPORTED_DEFLATE_LENGTH : 64; unsigned usezeros = 1; /*not sure if setting it to false for windowsize < 8192 is better or worse*/ unsigned numzeros = 0; @@ -1606,7 +1605,7 @@ static unsigned encodeLZ77(uivector* out, Hash* hash, if(windowsize == 0 || windowsize > 32768) return 60; /*error: windowsize smaller/larger than allowed*/ if((windowsize & (windowsize - 1)) != 0) return 90; /*error: must be power of two*/ - if(nicematch > MAX_SUPPORTED_DEFLATE_LENGTH) nicematch = (unsigned)MAX_SUPPORTED_DEFLATE_LENGTH; + if(nicematch > MAX_SUPPORTED_DEFLATE_LENGTH) nicematch = MAX_SUPPORTED_DEFLATE_LENGTH; for(pos = inpos; pos < insize; ++pos) { size_t wpos = pos & (windowsize - 1); /*position for in 'circular' hash buffers*/ @@ -1736,31 +1735,30 @@ static unsigned deflateNoCompression(ucvector* out, const unsigned char* data, s /*non compressed deflate block data: 1 bit BFINAL,2 bits BTYPE,(5 bits): it jumps to start of next byte, 2 bytes LEN, 2 bytes NLEN, LEN bytes literal DATA*/ - size_t i, j, numdeflateblocks = (datasize + 65534u) / 65535u; + size_t i, numdeflateblocks = (datasize + 65534u) / 65535u; unsigned datapos = 0; for(i = 0; i != numdeflateblocks; ++i) { unsigned BFINAL, BTYPE, LEN, NLEN; unsigned char firstbyte; + size_t pos = out->size; BFINAL = (i == numdeflateblocks - 1); BTYPE = 0; - firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1) << 1) + ((BTYPE & 2) << 1)); - ucvector_push_back(out, firstbyte); - LEN = 65535; if(datasize - datapos < 65535u) LEN = (unsigned)datasize - datapos; NLEN = 65535 - LEN; - ucvector_push_back(out, (unsigned char)(LEN & 255)); - ucvector_push_back(out, (unsigned char)(LEN >> 8u)); - ucvector_push_back(out, (unsigned char)(NLEN & 255)); - ucvector_push_back(out, (unsigned char)(NLEN >> 8u)); + if(!ucvector_resize(out, out->size + LEN + 5)) return 83; /*alloc fail*/ - /*Decompressed data*/ - for(j = 0; j < 65535 && datapos < datasize; ++j) { - ucvector_push_back(out, data[datapos++]); - } + firstbyte = (unsigned char)(BFINAL + ((BTYPE & 1u) << 1u) + ((BTYPE & 2u) << 1u)); + out->data[pos + 0] = firstbyte; + out->data[pos + 1] = (unsigned char)(LEN & 255); + out->data[pos + 2] = (unsigned char)(LEN >> 8u); + out->data[pos + 3] = (unsigned char)(NLEN & 255); + out->data[pos + 4] = (unsigned char)(NLEN >> 8u); + lodepng_memcpy(out->data + pos + 5, data + datapos, LEN); + datapos += LEN; } return 0; @@ -1776,7 +1774,7 @@ static void writeLZ77data(LodePNGBitWriter* writer, const uivector* lz77_encoded size_t i = 0; for(i = 0; i != lz77_encoded->size; ++i) { unsigned val = lz77_encoded->data[i]; - writeBitsReversed(writer, HuffmanTree_getCode(tree_ll, val), HuffmanTree_getLength(tree_ll, val)); + writeBitsReversed(writer, tree_ll->codes[val], tree_ll->lengths[val]); if(val > 256) /*for a length code, 3 more things have to be added*/ { unsigned length_index = val - FIRST_LENGTH_CODE_INDEX; unsigned n_length_extra_bits = LENGTHEXTRA[length_index]; @@ -1789,8 +1787,7 @@ static void writeLZ77data(LodePNGBitWriter* writer, const uivector* lz77_encoded unsigned distance_extra_bits = lz77_encoded->data[++i]; writeBits(writer, length_extra_bits, n_length_extra_bits); - writeBitsReversed(writer, HuffmanTree_getCode(tree_d, distance_code), - HuffmanTree_getLength(tree_d, distance_code)); + writeBitsReversed(writer, tree_d->codes[distance_code], tree_d->lengths[distance_code]); writeBits(writer, distance_extra_bits, n_distance_extra_bits); } } @@ -1818,42 +1815,45 @@ static unsigned deflateDynamic(LodePNGBitWriter* writer, Hash* hash, HuffmanTree tree_ll; /*tree for lit,len values*/ HuffmanTree tree_d; /*tree for distance codes*/ HuffmanTree tree_cl; /*tree for encoding the code lengths representing tree_ll and tree_d*/ - uivector frequencies_ll; /*frequency of lit,len codes*/ - uivector frequencies_d; /*frequency of dist codes*/ - uivector frequencies_cl; /*frequency of code length codes*/ - uivector bitlen_lld; /*lit,len,dist code lengths (int bits), literally (without repeat codes).*/ - uivector bitlen_lld_e; /*bitlen_lld encoded with repeat codes (this is a rudimentary run length compression)*/ - /*bitlen_cl is the code length code lengths ("clcl"). The bit lengths of codes to represent tree_cl - (these are written as is in the file, it would be crazy to compress these using yet another huffman - tree that needs to be represented by yet another set of code lengths)*/ - uivector bitlen_cl; + unsigned* frequencies_ll = 0; /*frequency of lit,len codes*/ + unsigned* frequencies_d = 0; /*frequency of dist codes*/ + unsigned* frequencies_cl = 0; /*frequency of code length codes*/ + unsigned* bitlen_lld = 0; /*lit,len,dist code lengths (int bits), literally (without repeat codes).*/ + unsigned* bitlen_lld_e = 0; /*bitlen_lld encoded with repeat codes (this is a rudimentary run length compression)*/ size_t datasize = dataend - datapos; /* - Due to the huffman compression of huffman tree representations ("two levels"), there are some analogies: + If we could call "bitlen_cl" the the code length code lengths ("clcl"), that is the bit lengths of codes to represent + tree_cl in CLCL_ORDER, then due to the huffman compression of huffman tree representations ("two levels"), there are + some analogies: bitlen_lld is to tree_cl what data is to tree_ll and tree_d. bitlen_lld_e is to bitlen_lld what lz77_encoded is to data. bitlen_cl is to bitlen_lld_e what bitlen_lld is to lz77_encoded. */ unsigned BFINAL = final; - size_t numcodes_ll, numcodes_d, i; + size_t i; + size_t numcodes_ll, numcodes_d, numcodes_lld, numcodes_lld_e, numcodes_cl; unsigned HLIT, HDIST, HCLEN; uivector_init(&lz77_encoded); HuffmanTree_init(&tree_ll); HuffmanTree_init(&tree_d); HuffmanTree_init(&tree_cl); - uivector_init(&frequencies_ll); - uivector_init(&frequencies_d); - uivector_init(&frequencies_cl); - uivector_init(&bitlen_lld); - uivector_init(&bitlen_lld_e); - uivector_init(&bitlen_cl); + /* could fit on stack, but >1KB is on the larger side so allocate instead */ + frequencies_ll = (unsigned*)lodepng_malloc(286 * sizeof(*frequencies_ll)); + frequencies_d = (unsigned*)lodepng_malloc(30 * sizeof(*frequencies_d)); + frequencies_cl = (unsigned*)lodepng_malloc(NUM_CODE_LENGTH_CODES * sizeof(*frequencies_cl)); + + if(!frequencies_ll || !frequencies_d || !frequencies_cl) error = 83; /*alloc fail*/ /*This while loop never loops due to a break at the end, it is here to allow breaking out of it to the cleanup phase on error conditions.*/ while(!error) { + lodepng_memset(frequencies_ll, 0, 286 * sizeof(*frequencies_ll)); + lodepng_memset(frequencies_d, 0, 30 * sizeof(*frequencies_d)); + lodepng_memset(frequencies_cl, 0, NUM_CODE_LENGTH_CODES * sizeof(*frequencies_cl)); + if(settings->use_lz77) { error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, settings->minmatch, settings->nicematch, settings->lazymatching); @@ -1863,94 +1863,92 @@ static unsigned deflateDynamic(LodePNGBitWriter* writer, Hash* hash, for(i = datapos; i < dataend; ++i) lz77_encoded.data[i - datapos] = data[i]; /*no LZ77, but still will be Huffman compressed*/ } - if(!uivector_resizev(&frequencies_ll, 286, 0)) ERROR_BREAK(83 /*alloc fail*/); - if(!uivector_resizev(&frequencies_d, 30, 0)) ERROR_BREAK(83 /*alloc fail*/); - /*Count the frequencies of lit, len and dist codes*/ for(i = 0; i != lz77_encoded.size; ++i) { unsigned symbol = lz77_encoded.data[i]; - ++frequencies_ll.data[symbol]; + ++frequencies_ll[symbol]; if(symbol > 256) { unsigned dist = lz77_encoded.data[i + 2]; - ++frequencies_d.data[dist]; + ++frequencies_d[dist]; i += 3; } } - frequencies_ll.data[256] = 1; /*there will be exactly 1 end code, at the end of the block*/ + frequencies_ll[256] = 1; /*there will be exactly 1 end code, at the end of the block*/ /*Make both huffman trees, one for the lit and len codes, one for the dist codes*/ - error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll.data, 257, frequencies_ll.size, 15); + error = HuffmanTree_makeFromFrequencies(&tree_ll, frequencies_ll, 257, 286, 15); if(error) break; /*2, not 1, is chosen for mincodes: some buggy PNG decoders require at least 2 symbols in the dist tree*/ - error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d.data, 2, frequencies_d.size, 15); + error = HuffmanTree_makeFromFrequencies(&tree_d, frequencies_d, 2, 30, 15); if(error) break; - numcodes_ll = tree_ll.numcodes; if(numcodes_ll > 286) numcodes_ll = 286; - numcodes_d = tree_d.numcodes; if(numcodes_d > 30) numcodes_d = 30; + numcodes_ll = LODEPNG_MIN(tree_ll.numcodes, 286); + numcodes_d = LODEPNG_MIN(tree_d.numcodes, 30); /*store the code lengths of both generated trees in bitlen_lld*/ - for(i = 0; i != numcodes_ll; ++i) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_ll, (unsigned)i)); - for(i = 0; i != numcodes_d; ++i) uivector_push_back(&bitlen_lld, HuffmanTree_getLength(&tree_d, (unsigned)i)); + numcodes_lld = numcodes_ll + numcodes_d; + bitlen_lld = (unsigned*)lodepng_malloc(numcodes_lld * sizeof(*bitlen_lld)); + /*numcodes_lld_e never needs more size than bitlen_lld*/ + bitlen_lld_e = (unsigned*)lodepng_malloc(numcodes_lld * sizeof(*bitlen_lld_e)); + if(!bitlen_lld || !bitlen_lld_e) ERROR_BREAK(83); /*alloc fail*/ + numcodes_lld_e = 0; + + for(i = 0; i != numcodes_ll; ++i) bitlen_lld[i] = tree_ll.lengths[i]; + for(i = 0; i != numcodes_d; ++i) bitlen_lld[numcodes_ll + i] = tree_d.lengths[i]; /*run-length compress bitlen_ldd into bitlen_lld_e by using repeat codes 16 (copy length 3-6 times), 17 (3-10 zeroes), 18 (11-138 zeroes)*/ - for(i = 0; i != (unsigned)bitlen_lld.size; ++i) { + for(i = 0; i != numcodes_lld; ++i) { unsigned j = 0; /*amount of repetitions*/ - while(i + j + 1 < (unsigned)bitlen_lld.size && bitlen_lld.data[i + j + 1] == bitlen_lld.data[i]) ++j; + while(i + j + 1 < numcodes_lld && bitlen_lld[i + j + 1] == bitlen_lld[i]) ++j; - if(bitlen_lld.data[i] == 0 && j >= 2) /*repeat code for zeroes*/ { + if(bitlen_lld[i] == 0 && j >= 2) /*repeat code for zeroes*/ { ++j; /*include the first zero*/ if(j <= 10) /*repeat code 17 supports max 10 zeroes*/ { - uivector_push_back(&bitlen_lld_e, 17); - uivector_push_back(&bitlen_lld_e, j - 3); + bitlen_lld_e[numcodes_lld_e++] = 17; + bitlen_lld_e[numcodes_lld_e++] = j - 3; } else /*repeat code 18 supports max 138 zeroes*/ { if(j > 138) j = 138; - uivector_push_back(&bitlen_lld_e, 18); - uivector_push_back(&bitlen_lld_e, j - 11); + bitlen_lld_e[numcodes_lld_e++] = 18; + bitlen_lld_e[numcodes_lld_e++] = j - 11; } i += (j - 1); } else if(j >= 3) /*repeat code for value other than zero*/ { size_t k; unsigned num = j / 6u, rest = j % 6u; - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); + bitlen_lld_e[numcodes_lld_e++] = bitlen_lld[i]; for(k = 0; k < num; ++k) { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, 6 - 3); + bitlen_lld_e[numcodes_lld_e++] = 16; + bitlen_lld_e[numcodes_lld_e++] = 6 - 3; } if(rest >= 3) { - uivector_push_back(&bitlen_lld_e, 16); - uivector_push_back(&bitlen_lld_e, rest - 3); + bitlen_lld_e[numcodes_lld_e++] = 16; + bitlen_lld_e[numcodes_lld_e++] = rest - 3; } else j -= rest; i += j; } else /*too short to benefit from repeat code*/ { - uivector_push_back(&bitlen_lld_e, bitlen_lld.data[i]); + bitlen_lld_e[numcodes_lld_e++] = bitlen_lld[i]; } } /*generate tree_cl, the huffmantree of huffmantrees*/ - - if(!uivector_resizev(&frequencies_cl, NUM_CODE_LENGTH_CODES, 0)) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i != bitlen_lld_e.size; ++i) { - ++frequencies_cl.data[bitlen_lld_e.data[i]]; + for(i = 0; i != numcodes_lld_e; ++i) { + ++frequencies_cl[bitlen_lld_e[i]]; /*after a repeat code come the bits that specify the number of repetitions, those don't need to be in the frequencies_cl calculation*/ - if(bitlen_lld_e.data[i] >= 16) ++i; + if(bitlen_lld_e[i] >= 16) ++i; } - error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl.data, - frequencies_cl.size, frequencies_cl.size, 7); + error = HuffmanTree_makeFromFrequencies(&tree_cl, frequencies_cl, + NUM_CODE_LENGTH_CODES, NUM_CODE_LENGTH_CODES, 7); if(error) break; - if(!uivector_resize(&bitlen_cl, tree_cl.numcodes)) ERROR_BREAK(83 /*alloc fail*/); - for(i = 0; i != tree_cl.numcodes; ++i) { - /*lengths of code length tree is in the order as specified by deflate*/ - bitlen_cl.data[i] = HuffmanTree_getLength(&tree_cl, CLCL_ORDER[i]); + /*compute amount of code-length-code-lengths to output*/ + numcodes_cl = NUM_CODE_LENGTH_CODES; + /*trim zeros at the end (using CLCL_ORDER), but minimum size must be 4 (see HCLEN below)*/ + while(numcodes_cl > 4u && tree_cl.lengths[CLCL_ORDER[numcodes_cl - 1u]] == 0) { + numcodes_cl--; } - while(bitlen_cl.data[bitlen_cl.size - 1] == 0 && bitlen_cl.size > 4) { - /*remove zeros at the end, but minimum size must be 4*/ - if(!uivector_resize(&bitlen_cl, bitlen_cl.size - 1)) ERROR_BREAK(83 /*alloc fail*/); - } - if(error) break; /* Write everything into the output @@ -1972,35 +1970,34 @@ static unsigned deflateDynamic(LodePNGBitWriter* writer, Hash* hash, writeBits(writer, 1, 1); /*second bit of BTYPE "dynamic"*/ /*write the HLIT, HDIST and HCLEN values*/ + /*all three sizes take trimmed ending zeroes into account, done either by HuffmanTree_makeFromFrequencies + or in the loop for numcodes_cl above, which saves space. */ HLIT = (unsigned)(numcodes_ll - 257); HDIST = (unsigned)(numcodes_d - 1); - HCLEN = (unsigned)bitlen_cl.size - 4; - /*trim zeroes for HCLEN. HLIT and HDIST were already trimmed at tree creation*/ - while(!bitlen_cl.data[HCLEN + 4 - 1] && HCLEN > 0) --HCLEN; + HCLEN = (unsigned)(numcodes_cl - 4); writeBits(writer, HLIT, 5); writeBits(writer, HDIST, 5); writeBits(writer, HCLEN, 4); - /*write the code lengths of the code length alphabet*/ - for(i = 0; i != HCLEN + 4; ++i) writeBits(writer, bitlen_cl.data[i], 3); + /*write the code lengths of the code length alphabet ("bitlen_cl")*/ + for(i = 0; i != numcodes_cl; ++i) writeBits(writer, tree_cl.lengths[CLCL_ORDER[i]], 3); /*write the lengths of the lit/len AND the dist alphabet*/ - for(i = 0; i != bitlen_lld_e.size; ++i) { - writeBitsReversed(writer, HuffmanTree_getCode(&tree_cl, bitlen_lld_e.data[i]), - HuffmanTree_getLength(&tree_cl, bitlen_lld_e.data[i])); + for(i = 0; i != numcodes_lld_e; ++i) { + writeBitsReversed(writer, tree_cl.codes[bitlen_lld_e[i]], tree_cl.lengths[bitlen_lld_e[i]]); /*extra bits of repeat codes*/ - if(bitlen_lld_e.data[i] == 16) writeBits(writer, bitlen_lld_e.data[++i], 2); - else if(bitlen_lld_e.data[i] == 17) writeBits(writer, bitlen_lld_e.data[++i], 3); - else if(bitlen_lld_e.data[i] == 18) writeBits(writer, bitlen_lld_e.data[++i], 7); + if(bitlen_lld_e[i] == 16) writeBits(writer, bitlen_lld_e[++i], 2); + else if(bitlen_lld_e[i] == 17) writeBits(writer, bitlen_lld_e[++i], 3); + else if(bitlen_lld_e[i] == 18) writeBits(writer, bitlen_lld_e[++i], 7); } /*write the compressed data symbols*/ writeLZ77data(writer, &lz77_encoded, &tree_ll, &tree_d); /*error: the length of the end code 256 must be larger than 0*/ - if(HuffmanTree_getLength(&tree_ll, 256) == 0) ERROR_BREAK(64); + if(tree_ll.lengths[256] == 0) ERROR_BREAK(64); /*write the end code*/ - writeBitsReversed(writer, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); + writeBitsReversed(writer, tree_ll.codes[256], tree_ll.lengths[256]); break; /*end of error-while*/ } @@ -2010,12 +2007,11 @@ static unsigned deflateDynamic(LodePNGBitWriter* writer, Hash* hash, HuffmanTree_cleanup(&tree_ll); HuffmanTree_cleanup(&tree_d); HuffmanTree_cleanup(&tree_cl); - uivector_cleanup(&frequencies_ll); - uivector_cleanup(&frequencies_d); - uivector_cleanup(&frequencies_cl); - uivector_cleanup(&bitlen_lld_e); - uivector_cleanup(&bitlen_lld); - uivector_cleanup(&bitlen_cl); + lodepng_free(frequencies_ll); + lodepng_free(frequencies_d); + lodepng_free(frequencies_cl); + lodepng_free(bitlen_lld); + lodepng_free(bitlen_lld_e); return error; } @@ -2034,27 +2030,29 @@ static unsigned deflateFixed(LodePNGBitWriter* writer, Hash* hash, HuffmanTree_init(&tree_ll); HuffmanTree_init(&tree_d); - generateFixedLitLenTree(&tree_ll); - generateFixedDistanceTree(&tree_d); + error = generateFixedLitLenTree(&tree_ll); + if(!error) error = generateFixedDistanceTree(&tree_d); - writeBits(writer, BFINAL, 1); - writeBits(writer, 1, 1); /*first bit of BTYPE*/ - writeBits(writer, 0, 1); /*second bit of BTYPE*/ + if(!error) { + writeBits(writer, BFINAL, 1); + writeBits(writer, 1, 1); /*first bit of BTYPE*/ + writeBits(writer, 0, 1); /*second bit of BTYPE*/ - if(settings->use_lz77) /*LZ77 encoded*/ { - uivector lz77_encoded; - uivector_init(&lz77_encoded); - error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, - settings->minmatch, settings->nicematch, settings->lazymatching); - if(!error) writeLZ77data(writer, &lz77_encoded, &tree_ll, &tree_d); - uivector_cleanup(&lz77_encoded); - } else /*no LZ77, but still will be Huffman compressed*/ { - for(i = datapos; i < dataend; ++i) { - writeBitsReversed(writer, HuffmanTree_getCode(&tree_ll, data[i]), HuffmanTree_getLength(&tree_ll, data[i])); + if(settings->use_lz77) /*LZ77 encoded*/ { + uivector lz77_encoded; + uivector_init(&lz77_encoded); + error = encodeLZ77(&lz77_encoded, hash, data, datapos, dataend, settings->windowsize, + settings->minmatch, settings->nicematch, settings->lazymatching); + if(!error) writeLZ77data(writer, &lz77_encoded, &tree_ll, &tree_d); + uivector_cleanup(&lz77_encoded); + } else /*no LZ77, but still will be Huffman compressed*/ { + for(i = datapos; i < dataend; ++i) { + writeBitsReversed(writer, tree_ll.codes[data[i]], tree_ll.lengths[data[i]]); + } } + /*add END code*/ + if(!error) writeBitsReversed(writer,tree_ll.codes[256], tree_ll.lengths[256]); } - /*add END code*/ - if(!error) writeBitsReversed(writer, HuffmanTree_getCode(&tree_ll, 256), HuffmanTree_getLength(&tree_ll, 256)); /*cleanup*/ HuffmanTree_cleanup(&tree_ll); @@ -2086,16 +2084,17 @@ static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t if(numdeflateblocks == 0) numdeflateblocks = 1; error = hash_init(&hash, settings->windowsize); - if(error) return error; - for(i = 0; i != numdeflateblocks && !error; ++i) { - unsigned final = (i == numdeflateblocks - 1); - size_t start = i * blocksize; - size_t end = start + blocksize; - if(end > insize) end = insize; + if(!error) { + for(i = 0; i != numdeflateblocks && !error; ++i) { + unsigned final = (i == numdeflateblocks - 1); + size_t start = i * blocksize; + size_t end = start + blocksize; + if(end > insize) end = insize; - if(settings->btype == 1) error = deflateFixed(&writer, &hash, in, start, end, settings, final); - else if(settings->btype == 2) error = deflateDynamic(&writer, &hash, in, start, end, settings, final); + if(settings->btype == 1) error = deflateFixed(&writer, &hash, in, start, end, settings, final); + else if(settings->btype == 2) error = deflateDynamic(&writer, &hash, in, start, end, settings, final); + } } hash_cleanup(&hash); @@ -2106,10 +2105,8 @@ static unsigned lodepng_deflatev(ucvector* out, const unsigned char* in, size_t unsigned lodepng_deflate(unsigned char** out, size_t* outsize, const unsigned char* in, size_t insize, const LodePNGCompressSettings* settings) { - unsigned error; - ucvector v; - ucvector_init_buffer(&v, *out, *outsize); - error = lodepng_deflatev(&v, in, insize, settings); + ucvector v = ucvector_init(*out, *outsize); + unsigned error = lodepng_deflatev(&v, in, insize, settings); *out = v.data; *outsize = v.size; return error; @@ -2162,8 +2159,9 @@ static unsigned adler32(const unsigned char* data, unsigned len) { #ifdef LODEPNG_COMPILE_DECODER -unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) { +static unsigned lodepng_zlib_decompressv(ucvector* out, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings) { unsigned error = 0; unsigned CM, CINFO, FDICT; @@ -2190,24 +2188,45 @@ unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const uns return 26; } - error = inflate(out, outsize, in + 2, insize - 2, settings); + error = inflatev(out, in + 2, insize - 2, settings); if(error) return error; if(!settings->ignore_adler32) { unsigned ADLER32 = lodepng_read32bitInt(&in[insize - 4]); - unsigned checksum = adler32(*out, (unsigned)(*outsize)); + unsigned checksum = adler32(out->data, (unsigned)(out->size)); if(checksum != ADLER32) return 58; /*error, adler checksum not correct, data must be corrupted*/ } return 0; /*no error*/ } -static unsigned zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) { + +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, + size_t insize, const LodePNGDecompressSettings* settings) { + ucvector v = ucvector_init(*out, *outsize); + unsigned error = lodepng_zlib_decompressv(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; +} + +/*expected_size is expected output size, to avoid intermediate allocations. Set to 0 if not known. */ +static unsigned zlib_decompress(unsigned char** out, size_t* outsize, size_t expected_size, + const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { if(settings->custom_zlib) { return settings->custom_zlib(out, outsize, in, insize, settings); } else { - return lodepng_zlib_decompress(out, outsize, in, insize, settings); + unsigned error; + ucvector v = ucvector_init(*out, *outsize); + if(expected_size) { + /*reserve the memory to avoid intermediate reallocations*/ + ucvector_resize(&v, *outsize + expected_size); + v.size = *outsize; + } + error = lodepng_zlib_decompressv(&v, in, insize, settings); + *out = v.data; + *outsize = v.size; + return error; } } @@ -2229,7 +2248,7 @@ unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, const unsig if(!error) { *outsize = deflatesize + 6; *out = (unsigned char*)lodepng_malloc(*outsize); - if(!out) error = 83; /*alloc fail*/ + if(!*out) error = 83; /*alloc fail*/ } if(!error) { @@ -2267,9 +2286,10 @@ static unsigned zlib_compress(unsigned char** out, size_t* outsize, const unsign #else /*no LODEPNG_COMPILE_ZLIB*/ #ifdef LODEPNG_COMPILE_DECODER -static unsigned zlib_decompress(unsigned char** out, size_t* outsize, const unsigned char* in, - size_t insize, const LodePNGDecompressSettings* settings) { +static unsigned zlib_decompress(unsigned char** out, size_t* outsize, size_t expected_size, + const unsigned char* in, size_t insize, const LodePNGDecompressSettings* settings) { if(!settings->custom_zlib) return 87; /*no custom zlib function provided */ + (void)expected_size; return settings->custom_zlib(out, outsize, in, insize, settings); } #endif /*LODEPNG_COMPILE_DECODER*/ @@ -2405,7 +2425,7 @@ static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned ch unsigned result = 0; size_t i; for(i = 0 ; i < nbits; ++i) { - result <<= 1; + result <<= 1u; result |= (unsigned)readBitFromReversedStream(bitpointer, bitstream); } return result; @@ -2413,8 +2433,8 @@ static unsigned readBitsFromReversedStream(size_t* bitpointer, const unsigned ch static void setBitOfReversedStream(size_t* bitpointer, unsigned char* bitstream, unsigned char bit) { /*the current bit in bitstream may be 0 or 1 for this to work*/ - if(bit == 0) bitstream[(*bitpointer) >> 3] &= (unsigned char)(~(1 << (7 - ((*bitpointer) & 0x7)))); - else bitstream[(*bitpointer) >> 3] |= (1 << (7 - ((*bitpointer) & 0x7))); + if(bit == 0) bitstream[(*bitpointer) >> 3u] &= (unsigned char)(~(1u << (7u - ((*bitpointer) & 7u)))); + else bitstream[(*bitpointer) >> 3u] |= (1u << (7u - ((*bitpointer) & 7u))); ++(*bitpointer); } @@ -2472,55 +2492,66 @@ void lodepng_chunk_generate_crc(unsigned char* chunk) { lodepng_set32bitInt(chunk + 8 + length, CRC); } -unsigned char* lodepng_chunk_next(unsigned char* chunk) { +unsigned char* lodepng_chunk_next(unsigned char* chunk, unsigned char* end) { + if(chunk >= end || end - chunk < 12) return end; /*too small to contain a chunk*/ if(chunk[0] == 0x89 && chunk[1] == 0x50 && chunk[2] == 0x4e && chunk[3] == 0x47 && chunk[4] == 0x0d && chunk[5] == 0x0a && chunk[6] == 0x1a && chunk[7] == 0x0a) { /* Is PNG magic header at start of PNG file. Jump to first actual chunk. */ return chunk + 8; } else { - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; - return chunk + total_chunk_length; + size_t total_chunk_length; + unsigned char* result; + if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return end; + result = chunk + total_chunk_length; + if(result < chunk) return end; /*pointer overflow*/ + return result; } } -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk) { +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk, const unsigned char* end) { + if(chunk >= end || end - chunk < 12) return end; /*too small to contain a chunk*/ if(chunk[0] == 0x89 && chunk[1] == 0x50 && chunk[2] == 0x4e && chunk[3] == 0x47 && chunk[4] == 0x0d && chunk[5] == 0x0a && chunk[6] == 0x1a && chunk[7] == 0x0a) { /* Is PNG magic header at start of PNG file. Jump to first actual chunk. */ return chunk + 8; } else { - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; - return chunk + total_chunk_length; + size_t total_chunk_length; + const unsigned char* result; + if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return end; + result = chunk + total_chunk_length; + if(result < chunk) return end; /*pointer overflow*/ + return result; } } -unsigned char* lodepng_chunk_find(unsigned char* chunk, const unsigned char* end, const char type[5]) { +unsigned char* lodepng_chunk_find(unsigned char* chunk, unsigned char* end, const char type[5]) { for(;;) { - if(chunk + 12 >= end) return 0; + if(chunk >= end || end - chunk < 12) return 0; /* past file end: chunk + 12 > end */ if(lodepng_chunk_type_equals(chunk, type)) return chunk; - chunk = lodepng_chunk_next(chunk); + chunk = lodepng_chunk_next(chunk, end); } } const unsigned char* lodepng_chunk_find_const(const unsigned char* chunk, const unsigned char* end, const char type[5]) { for(;;) { - if(chunk + 12 >= end) return 0; + if(chunk >= end || end - chunk < 12) return 0; /* past file end: chunk + 12 > end */ if(lodepng_chunk_type_equals(chunk, type)) return chunk; - chunk = lodepng_chunk_next_const(chunk); + chunk = lodepng_chunk_next_const(chunk, end); } } -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk) { +unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk) { unsigned i; - unsigned total_chunk_length = lodepng_chunk_length(chunk) + 12; + size_t total_chunk_length, new_length; unsigned char *chunk_start, *new_buffer; - size_t new_length = (*outlength) + total_chunk_length; - if(new_length < total_chunk_length || new_length < (*outlength)) return 77; /*integer overflow happened*/ + + if(lodepng_addofl(lodepng_chunk_length(chunk), 12, &total_chunk_length)) return 77; + if(lodepng_addofl(*outsize, total_chunk_length, &new_length)) return 77; new_buffer = (unsigned char*)lodepng_realloc(*out, new_length); if(!new_buffer) return 83; /*alloc fail*/ (*out) = new_buffer; - (*outlength) = new_length; + (*outsize) = new_length; chunk_start = &(*out)[new_length - total_chunk_length]; for(i = 0; i != total_chunk_length; ++i) chunk_start[i] = chunk[i]; @@ -2528,29 +2559,36 @@ unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsi return 0; } -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data) { - unsigned i; - unsigned char *chunk, *new_buffer; - size_t new_length = (*outlength) + length + 12; - if(new_length < length + 12 || new_length < (*outlength)) return 77; /*integer overflow happened*/ - new_buffer = (unsigned char*)lodepng_realloc(*out, new_length); - if(!new_buffer) return 83; /*alloc fail*/ - (*out) = new_buffer; - (*outlength) = new_length; - chunk = &(*out)[(*outlength) - length - 12]; +/*Sets length and name and allocates the space for data and crc but does not +set data or crc yet. Returns the start of the chunk in chunk. The start of +the data is at chunk + 8. To finalize chunk, add the data, then use +lodepng_chunk_generate_crc */ +static unsigned lodepng_chunk_init(unsigned char** chunk, + ucvector* out, + unsigned length, const char* type) { + size_t new_length = out->size; + if(lodepng_addofl(new_length, length, &new_length)) return 77; + if(lodepng_addofl(new_length, 12, &new_length)) return 77; + if(!ucvector_resize(out, new_length)) return 83; /*alloc fail*/ + *chunk = out->data + new_length - length - 12u; /*1: length*/ - lodepng_set32bitInt(chunk, (unsigned)length); + lodepng_set32bitInt(*chunk, length); /*2: chunk name (4 letters)*/ - chunk[4] = (unsigned char)type[0]; - chunk[5] = (unsigned char)type[1]; - chunk[6] = (unsigned char)type[2]; - chunk[7] = (unsigned char)type[3]; + lodepng_memcpy(*chunk + 4, type, 4); + + return 0; +} + +/* like lodepng_chunk_create but with custom allocsize */ +static unsigned lodepng_chunk_createv(ucvector* out, + unsigned length, const char* type, const unsigned char* data) { + unsigned char* chunk; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, length, type)); /*3: the data*/ - for(i = 0; i != length; ++i) chunk[8 + i] = data[i]; + lodepng_memcpy(chunk + 8, data, length); /*4: CRC (of the chunkname characters and the data)*/ lodepng_chunk_generate_crc(chunk); @@ -2558,6 +2596,15 @@ unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned l return 0; } +unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, + unsigned length, const char* type, const unsigned char* data) { + ucvector v = ucvector_init(*out, *outsize); + unsigned error = lodepng_chunk_createv(&v, length, type, data); + *out = v.data; + *outsize = v.size; + return error; +} + /* ////////////////////////////////////////////////////////////////////////// */ /* / Color types, channels, bits / */ /* ////////////////////////////////////////////////////////////////////////// */ @@ -2571,6 +2618,7 @@ static unsigned checkColorValidity(LodePNGColorType colortype, unsigned bd) { case LCT_PALETTE: if(!(bd == 1 || bd == 2 || bd == 4 || bd == 8 )) return 37; break; case LCT_GREY_ALPHA: if(!( bd == 8 || bd == 16)) return 37; break; case LCT_RGBA: if(!( bd == 8 || bd == 16)) return 37; break; + case LCT_MAX_OCTET_VALUE: return 31; /* invalid color type */ default: return 31; /* invalid color type */ } return 0; /*allowed color type / bits combination*/ @@ -2583,6 +2631,7 @@ static unsigned getNumColorChannels(LodePNGColorType colortype) { case LCT_PALETTE: return 1; case LCT_GREY_ALPHA: return 2; case LCT_RGBA: return 4; + case LCT_MAX_OCTET_VALUE: return 0; /* invalid color type */ default: return 0; /*invalid color type*/ } } @@ -2603,10 +2652,12 @@ void lodepng_color_mode_init(LodePNGColorMode* info) { info->palettesize = 0; } -void lodepng_color_mode_alloc_palette(LodePNGColorMode* info) { +/*allocates palette memory if needed, and initializes all colors to black*/ +static void lodepng_color_mode_alloc_palette(LodePNGColorMode* info) { size_t i; - /*room for 256 colors with 4 bytes each. Using realloc to avoid leak if it is being overwritten*/ - info->palette = (unsigned char*)lodepng_realloc(info->palette, 1024); + /*if the palette is already allocated, it will have size 1024 so no reallocation needed in that case*/ + /*the palette must have room for up to 256 colors with 4 bytes each.*/ + if(!info->palette) info->palette = (unsigned char*)lodepng_malloc(1024); if(!info->palette) return; /*alloc fail*/ for(i = 0; i != 256; ++i) { /*Initialize all unused colors with black, the value used for invalid palette indices. @@ -2624,13 +2675,12 @@ void lodepng_color_mode_cleanup(LodePNGColorMode* info) { } unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source) { - size_t i; lodepng_color_mode_cleanup(dest); - *dest = *source; + lodepng_memcpy(dest, source, sizeof(LodePNGColorMode)); if(source->palette) { dest->palette = (unsigned char*)lodepng_malloc(1024); if(!dest->palette && source->palettesize) return 83; /*alloc fail*/ - for(i = 0; i != source->palettesize * 4; ++i) dest->palette[i] = source->palette[i]; + lodepng_memcpy(dest->palette, source->palette, source->palettesize * 4); } return 0; } @@ -2672,6 +2722,9 @@ unsigned lodepng_palette_add(LodePNGColorMode* info, lodepng_color_mode_alloc_palette(info); if(!info->palette) return 83; /*alloc fail*/ } + if(info->palettesize >= 256) { + return 108; /*too many palette values*/ + } info->palette[4 * info->palettesize + 0] = r; info->palette[4 * info->palettesize + 1] = g; info->palette[4 * info->palettesize + 2] = b; @@ -2727,18 +2780,18 @@ size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* colo #ifdef LODEPNG_COMPILE_PNG -#ifdef LODEPNG_COMPILE_DECODER /*in an idat chunk, each scanline is a multiple of 8 bits, unlike the lodepng output buffer, and in addition has one extra byte per line: the filter byte. So this gives a larger -result than lodepng_get_raw_size. */ -static size_t lodepng_get_raw_size_idat(unsigned w, unsigned h, const LodePNGColorMode* color) { - size_t bpp = lodepng_get_bpp(color); - /* + 1 for the filter byte, and possibly plus padding bits per line */ +result than lodepng_get_raw_size. Set h to 1 to get the size of 1 row including filter byte. */ +static size_t lodepng_get_raw_size_idat(unsigned w, unsigned h, unsigned bpp) { + /* + 1 for the filter byte, and possibly plus padding bits per line. */ + /* Ignoring casts, the expression is equal to (w * bpp + 7) / 8 + 1, but avoids overflow of w * bpp */ size_t line = ((size_t)(w / 8u) * bpp) + 1u + ((w & 7u) * bpp + 7u) / 8u; return (size_t)h * line; } +#ifdef LODEPNG_COMPILE_DECODER /*Safely checks whether size_t overflow can be caused due to amount of pixels. This check is overcautious rather than precise. If this check indicates no overflow, you can safely compute in a size_t (but not an unsigned): @@ -2828,27 +2881,29 @@ static unsigned LodePNGText_copy(LodePNGInfo* dest, const LodePNGInfo* source) { return 0; } -void lodepng_clear_text(LodePNGInfo* info) { - LodePNGText_cleanup(info); +static unsigned lodepng_add_text_sized(LodePNGInfo* info, const char* key, const char* str, size_t size) { + char** new_keys = (char**)(lodepng_realloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); + char** new_strings = (char**)(lodepng_realloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); + + if(new_keys) info->text_keys = new_keys; + if(new_strings) info->text_strings = new_strings; + + if(!new_keys || !new_strings) return 83; /*alloc fail*/ + + ++info->text_num; + info->text_keys[info->text_num - 1] = alloc_string(key); + info->text_strings[info->text_num - 1] = alloc_string_sized(str, size); + if(!info->text_keys[info->text_num - 1] || !info->text_strings[info->text_num - 1]) return 83; /*alloc fail*/ + + return 0; } unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str) { - char** new_keys = (char**)(lodepng_realloc(info->text_keys, sizeof(char*) * (info->text_num + 1))); - char** new_strings = (char**)(lodepng_realloc(info->text_strings, sizeof(char*) * (info->text_num + 1))); - if(!new_keys || !new_strings) { - lodepng_free(new_keys); - lodepng_free(new_strings); - return 83; /*alloc fail*/ - } + return lodepng_add_text_sized(info, key, str, lodepng_strlen(str)); +} - ++info->text_num; - info->text_keys = new_keys; - info->text_strings = new_strings; - - info->text_keys[info->text_num - 1] = alloc_string(key); - info->text_strings[info->text_num - 1] = alloc_string(str); - - return 0; +void lodepng_clear_text(LodePNGInfo* info) { + LodePNGText_cleanup(info); } /******************************************************************************/ @@ -2893,34 +2948,35 @@ void lodepng_clear_itext(LodePNGInfo* info) { LodePNGIText_cleanup(info); } -unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str) { +static unsigned lodepng_add_itext_sized(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str, size_t size) { char** new_keys = (char**)(lodepng_realloc(info->itext_keys, sizeof(char*) * (info->itext_num + 1))); char** new_langtags = (char**)(lodepng_realloc(info->itext_langtags, sizeof(char*) * (info->itext_num + 1))); char** new_transkeys = (char**)(lodepng_realloc(info->itext_transkeys, sizeof(char*) * (info->itext_num + 1))); char** new_strings = (char**)(lodepng_realloc(info->itext_strings, sizeof(char*) * (info->itext_num + 1))); - if(!new_keys || !new_langtags || !new_transkeys || !new_strings) { - lodepng_free(new_keys); - lodepng_free(new_langtags); - lodepng_free(new_transkeys); - lodepng_free(new_strings); - return 83; /*alloc fail*/ - } + + if(new_keys) info->itext_keys = new_keys; + if(new_langtags) info->itext_langtags = new_langtags; + if(new_transkeys) info->itext_transkeys = new_transkeys; + if(new_strings) info->itext_strings = new_strings; + + if(!new_keys || !new_langtags || !new_transkeys || !new_strings) return 83; /*alloc fail*/ ++info->itext_num; - info->itext_keys = new_keys; - info->itext_langtags = new_langtags; - info->itext_transkeys = new_transkeys; - info->itext_strings = new_strings; info->itext_keys[info->itext_num - 1] = alloc_string(key); info->itext_langtags[info->itext_num - 1] = alloc_string(langtag); info->itext_transkeys[info->itext_num - 1] = alloc_string(transkey); - info->itext_strings[info->itext_num - 1] = alloc_string(str); + info->itext_strings[info->itext_num - 1] = alloc_string_sized(str, size); return 0; } +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str) { + return lodepng_add_itext_sized(info, key, langtag, transkey, str, lodepng_strlen(str)); +} + /* same as set but does not delete */ static unsigned lodepng_assign_icc(LodePNGInfo* info, const char* name, const unsigned char* profile, unsigned profile_size) { if(profile_size == 0) return 100; /*invalid ICC profile size*/ @@ -2992,7 +3048,7 @@ void lodepng_info_cleanup(LodePNGInfo* info) { unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source) { lodepng_info_cleanup(dest); - *dest = *source; + lodepng_memcpy(dest, source, sizeof(LodePNGInfo)); lodepng_color_mode_init(&dest->color); CERROR_TRY_RETURN(lodepng_color_mode_copy(&dest->color, &source->color)); @@ -3036,8 +3092,7 @@ struct ColorTree { }; static void color_tree_init(ColorTree* tree) { - int i; - for(i = 0; i != 16; ++i) tree->children[i] = 0; + lodepng_memset(tree->children, 0, 16 * sizeof(*tree->children)); tree->index = -1; } @@ -3069,19 +3124,22 @@ static int color_tree_has(ColorTree* tree, unsigned char r, unsigned char g, uns #endif /*LODEPNG_COMPILE_ENCODER*/ /*color is not allowed to already exist. -Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist")*/ -static void color_tree_add(ColorTree* tree, - unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned index) { +Index should be >= 0 (it's signed to be compatible with using -1 for "doesn't exist") +Returns error code, or 0 if ok*/ +static unsigned color_tree_add(ColorTree* tree, + unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned index) { int bit; for(bit = 0; bit < 8; ++bit) { int i = 8 * ((r >> bit) & 1) + 4 * ((g >> bit) & 1) + 2 * ((b >> bit) & 1) + 1 * ((a >> bit) & 1); if(!tree->children[i]) { tree->children[i] = (ColorTree*)lodepng_malloc(sizeof(ColorTree)); + if(!tree->children[i]) return 83; /*alloc fail*/ color_tree_init(tree->children[i]); } tree = tree->children[i]; } tree->index = (int)index; + return 0; } /*put a pixel, given its RGBA color, into image of any color type*/ @@ -3094,7 +3152,7 @@ static unsigned rgba8ToPixel(unsigned char* out, size_t i, else if(mode->bitdepth == 16) out[i * 2 + 0] = out[i * 2 + 1] = gray; else { /*take the most significant bits of gray*/ - gray = (gray >> (8 - mode->bitdepth)) & ((1 << mode->bitdepth) - 1); + gray = ((unsigned)gray >> (8u - mode->bitdepth)) & ((1u << mode->bitdepth) - 1u); addColorBits(out, i, mode->bitdepth, gray); } } else if(mode->colortype == LCT_RGB) { @@ -3450,9 +3508,13 @@ unsigned lodepng_convert(unsigned char* out, const unsigned char* in, size_t numpixels = (size_t)w * (size_t)h; unsigned error = 0; + if(mode_in->colortype == LCT_PALETTE && !mode_in->palette) { + return 107; /* error: must provide palette if input mode is palette */ + } + if(lodepng_color_mode_equal(mode_out, mode_in)) { size_t numbytes = lodepng_get_raw_size(w, h, mode_in); - for(i = 0; i != numbytes; ++i) out[i] = in[i]; + lodepng_memcpy(out, in, numbytes); return 0; } @@ -3469,9 +3531,9 @@ unsigned lodepng_convert(unsigned char* out, const unsigned char* in, /*if the input was also palette with same bitdepth, then the color types are also equal, so copy literally. This to preserve the exact indices that were in the PNG even in case there are duplicate colors in the palette.*/ - if (mode_in->colortype == LCT_PALETTE && mode_in->bitdepth == mode_out->bitdepth) { + if(mode_in->colortype == LCT_PALETTE && mode_in->bitdepth == mode_out->bitdepth) { size_t numbytes = lodepng_get_raw_size(w, h, mode_in); - for(i = 0; i != numbytes; ++i) out[i] = in[i]; + lodepng_memcpy(out, in, numbytes); return 0; } } @@ -3479,26 +3541,29 @@ unsigned lodepng_convert(unsigned char* out, const unsigned char* in, color_tree_init(&tree); for(i = 0; i != palsize; ++i) { const unsigned char* p = &palette[i * 4]; - color_tree_add(&tree, p[0], p[1], p[2], p[3], (unsigned)i); + error = color_tree_add(&tree, p[0], p[1], p[2], p[3], (unsigned)i); + if(error) break; } } - if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) { - for(i = 0; i != numpixels; ++i) { - unsigned short r = 0, g = 0, b = 0, a = 0; - getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); - rgba16ToPixel(out, i, mode_out, r, g, b, a); - } - } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGBA) { - getPixelColorsRGBA8(out, numpixels, in, mode_in); - } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGB) { - getPixelColorsRGB8(out, numpixels, in, mode_in); - } else { - unsigned char r = 0, g = 0, b = 0, a = 0; - for(i = 0; i != numpixels; ++i) { - getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); - error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); - if (error) break; + if(!error) { + if(mode_in->bitdepth == 16 && mode_out->bitdepth == 16) { + for(i = 0; i != numpixels; ++i) { + unsigned short r = 0, g = 0, b = 0, a = 0; + getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); + rgba16ToPixel(out, i, mode_out, r, g, b, a); + } + } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGBA) { + getPixelColorsRGBA8(out, numpixels, in, mode_in); + } else if(mode_out->bitdepth == 8 && mode_out->colortype == LCT_RGB) { + getPixelColorsRGB8(out, numpixels, in, mode_in); + } else { + unsigned char r = 0, g = 0, b = 0, a = 0; + for(i = 0; i != numpixels; ++i) { + getPixelColorRGBA8(&r, &g, &b, &a, in, i, mode_in); + error = rgba8ToPixel(out, i, mode_out, &tree, r, g, b, a); + if(error) break; + } } } @@ -3603,12 +3668,13 @@ static unsigned getValueRequiredBits(unsigned char value) { } /*stats must already have been inited. */ -void lodepng_compute_color_stats(LodePNGColorStats* stats, - const unsigned char* in, unsigned w, unsigned h, - const LodePNGColorMode* mode_in) { +unsigned lodepng_compute_color_stats(LodePNGColorStats* stats, + const unsigned char* in, unsigned w, unsigned h, + const LodePNGColorMode* mode_in) { size_t i; ColorTree tree; size_t numpixels = (size_t)w * (size_t)h; + unsigned error = 0; /* mark things as done already if it would be impossible to have a more expensive case */ unsigned colored_done = lodepng_is_greyscale_type(mode_in) ? 1 : 0; @@ -3638,13 +3704,14 @@ void lodepng_compute_color_stats(LodePNGColorStats* stats, if(!numcolors_done) { for(i = 0; i < stats->numcolors; i++) { const unsigned char* color = &stats->palette[i * 4]; - color_tree_add(&tree, color[0], color[1], color[2], color[3], (unsigned)i); + error = color_tree_add(&tree, color[0], color[1], color[2], color[3], (unsigned)i); + if(error) goto cleanup; } } /*Check if the 16-bit input is truly 16-bit*/ if(mode_in->bitdepth == 16 && !sixteen) { - unsigned short r, g, b, a; + unsigned short r = 0, g = 0, b = 0, a = 0; for(i = 0; i != numpixels; ++i) { getPixelColorRGBA16(&r, &g, &b, &a, in, i, mode_in); if((r & 255) != ((r >> 8) & 255) || (g & 255) != ((g >> 8) & 255) || @@ -3742,7 +3809,8 @@ void lodepng_compute_color_stats(LodePNGColorStats* stats, if(!numcolors_done) { if(!color_tree_has(&tree, r, g, b, a)) { - color_tree_add(&tree, r, g, b, a, stats->numcolors); + error = color_tree_add(&tree, r, g, b, a, stats->numcolors); + if(error) goto cleanup; if(stats->numcolors < 256) { unsigned char* p = stats->palette; unsigned n = stats->numcolors; @@ -3778,15 +3846,18 @@ void lodepng_compute_color_stats(LodePNGColorStats* stats, stats->key_b += (stats->key_b << 8); } +cleanup: color_tree_cleanup(&tree); + return error; } #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*Adds a single color to the color stats. The stats must already have been inited. The color must be given as 16-bit (with 2 bytes repeating for 8-bit and 65535 for opaque alpha channel). This function is expensive, do not call it for all pixels of an image but only for a few additional values. */ -static void lodepng_color_stats_add(LodePNGColorStats* stats, - unsigned r, unsigned g, unsigned b, unsigned a) { +static unsigned lodepng_color_stats_add(LodePNGColorStats* stats, + unsigned r, unsigned g, unsigned b, unsigned a) { + unsigned error = 0; unsigned char image[8]; LodePNGColorMode mode; lodepng_color_mode_init(&mode); @@ -3794,14 +3865,22 @@ static void lodepng_color_stats_add(LodePNGColorStats* stats, image[4] = b >> 8; image[5] = b; image[6] = a >> 8; image[7] = a; mode.bitdepth = 16; mode.colortype = LCT_RGBA; - lodepng_compute_color_stats(stats, image, 1, 1, &mode); + error = lodepng_compute_color_stats(stats, image, 1, 1, &mode); lodepng_color_mode_cleanup(&mode); + return error; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -unsigned auto_choose_color(LodePNGColorMode* mode_out, - const LodePNGColorMode* mode_in, - const LodePNGColorStats* stats) { +/*Computes a minimal PNG color model that can contain all colors as indicated by the stats. +The stats should be computed with lodepng_compute_color_stats. +mode_in is raw color profile of the image the stats were computed on, to copy palette order from when relevant. +Minimal PNG color model means the color type and bit depth that gives smallest amount of bits in the output image, +e.g. gray if only grayscale pixels, palette if less than 256 colors, color key if only single transparent color, ... +This is used if auto_convert is enabled (it is by default). +*/ +static unsigned auto_choose_color(LodePNGColorMode* mode_out, + const LodePNGColorMode* mode_in, + const LodePNGColorStats* stats) { unsigned error = 0; unsigned palettebits; size_t i, n; @@ -3828,7 +3907,7 @@ unsigned auto_choose_color(LodePNGColorMode* mode_out, palettebits = n <= 2 ? 1 : (n <= 4 ? 2 : (n <= 16 ? 4 : 8)); palette_ok = n <= 256 && bits <= 8 && n != 0; /*n==0 means likely numcolors wasn't computed*/ if(numpixels < n * 2) palette_ok = 0; /*don't add palette overhead if image has only a few pixels*/ - if(gray_ok && bits <= palettebits) palette_ok = 0; /*gray is less overhead*/ + if(gray_ok && !alpha && bits <= palettebits) palette_ok = 0; /*gray is less overhead*/ if(!stats->allow_palette) palette_ok = 0; if(palette_ok) { @@ -4090,7 +4169,7 @@ static unsigned unfilterScanline(unsigned char* recon, const unsigned char* scan } } break; - default: return 36; /*error: nonexistent filter type given*/ + default: return 36; /*error: invalid filter type given*/ } return 0; } @@ -4109,7 +4188,8 @@ static unsigned unfilter(unsigned char* out, const unsigned char* in, unsigned w /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ size_t bytewidth = (bpp + 7u) / 8u; - size_t linebytes = (w * bpp + 7u) / 8u; + /*the width of a scanline in bytes, not including the filter type*/ + size_t linebytes = lodepng_get_raw_size_idat(w, 1, bpp) - 1u; for(y = 0; y < h; ++y) { size_t outindex = linebytes * y; @@ -4149,7 +4229,8 @@ static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsig for(y = 0; y < passh[i]; ++y) for(x = 0; x < passw[i]; ++x) { size_t pixelinstart = passstart[i] + (y * passw[i] + x) * bytewidth; - size_t pixeloutstart = ((ADAM7_IY[i] + y * ADAM7_DY[i]) * w + ADAM7_IX[i] + x * ADAM7_DX[i]) * bytewidth; + size_t pixeloutstart = ((ADAM7_IY[i] + (size_t)y * ADAM7_DY[i]) * (size_t)w + + ADAM7_IX[i] + (size_t)x * ADAM7_DX[i]) * bytewidth; for(b = 0; b < bytewidth; ++b) { out[pixeloutstart + b] = in[pixelinstart + b]; } @@ -4164,7 +4245,7 @@ static void Adam7_deinterlace(unsigned char* out, const unsigned char* in, unsig for(y = 0; y < passh[i]; ++y) for(x = 0; x < passw[i]; ++x) { ibp = (8 * passstart[i]) + (y * ilinebits + x * bpp); - obp = (ADAM7_IY[i] + y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + x * ADAM7_DX[i]) * bpp; + obp = (ADAM7_IY[i] + (size_t)y * ADAM7_DY[i]) * olinebits + (ADAM7_IX[i] + (size_t)x * ADAM7_DX[i]) * bpp; for(b = 0; b < bpp; ++b) { unsigned char bit = readBitFromReversedStream(&ibp, in); setBitOfReversedStream(&obp, out, bit); @@ -4329,7 +4410,6 @@ static unsigned readChunk_bKGD(LodePNGInfo* info, const unsigned char* data, siz static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) { unsigned error = 0; char *key = 0, *str = 0; - unsigned i; while(!error) /*not really a while loop, only used to break on error*/ { unsigned length, string2_begin; @@ -4343,8 +4423,8 @@ static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, siz key = (char*)lodepng_malloc(length + 1); if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(key, data, length); key[length] = 0; - for(i = 0; i != length; ++i) key[i] = (char)data[i]; string2_begin = length + 1; /*skip keyword null terminator*/ @@ -4352,8 +4432,8 @@ static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, siz str = (char*)lodepng_malloc(length + 1); if(!str) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(str, data + string2_begin, length); str[length] = 0; - for(i = 0; i != length; ++i) str[i] = (char)data[string2_begin + i]; error = lodepng_add_text(info, key, str); @@ -4370,13 +4450,11 @@ static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, siz static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecompressSettings* zlibsettings, const unsigned char* data, size_t chunkLength) { unsigned error = 0; - unsigned i; unsigned length, string2_begin; char *key = 0; - ucvector decoded; - - ucvector_init(&decoded); + unsigned char* str = 0; + size_t size = 0; while(!error) /*not really a while loop, only used to break on error*/ { for(length = 0; length < chunkLength && data[length] != 0; ++length) ; @@ -4386,8 +4464,8 @@ static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecompressSetting key = (char*)lodepng_malloc(length + 1); if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(key, data, length); key[length] = 0; - for(i = 0; i != length; ++i) key[i] = (char)data[i]; if(data[length + 1] != 0) CERROR_BREAK(error, 72); /*the 0 byte indicating compression must be 0*/ @@ -4396,19 +4474,16 @@ static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecompressSetting length = (unsigned)chunkLength - string2_begin; /*will fail if zlib error, e.g. if length is too small*/ - error = zlib_decompress(&decoded.data, &decoded.size, - &data[string2_begin], + error = zlib_decompress(&str, &size, 0, &data[string2_begin], length, zlibsettings); if(error) break; - ucvector_push_back(&decoded, 0); - - error = lodepng_add_text(info, key, (char*)decoded.data); + error = lodepng_add_text_sized(info, key, (char*)str, size); break; } lodepng_free(key); - ucvector_cleanup(&decoded); + lodepng_free(str); return error; } @@ -4421,8 +4496,6 @@ static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSetting unsigned length, begin, compressed; char *key = 0, *langtag = 0, *transkey = 0; - ucvector decoded; - ucvector_init(&decoded); /* TODO: only use in case of compressed text */ while(!error) /*not really a while loop, only used to break on error*/ { /*Quick check if the chunk length isn't too small. Even without check @@ -4437,8 +4510,8 @@ static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSetting key = (char*)lodepng_malloc(length + 1); if(!key) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(key, data, length); key[length] = 0; - for(i = 0; i != length; ++i) key[i] = (char)data[i]; /*read the compression method*/ compressed = data[length + 1]; @@ -4455,8 +4528,8 @@ static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSetting langtag = (char*)lodepng_malloc(length + 1); if(!langtag) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(langtag, data + begin, length); langtag[length] = 0; - for(i = 0; i != length; ++i) langtag[i] = (char)data[begin + i]; /*read the transkey*/ begin += length + 1; @@ -4466,8 +4539,8 @@ static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSetting transkey = (char*)lodepng_malloc(length + 1); if(!transkey) CERROR_BREAK(error, 83); /*alloc fail*/ + lodepng_memcpy(transkey, data + begin, length); transkey[length] = 0; - for(i = 0; i != length; ++i) transkey[i] = (char)data[begin + i]; /*read the actual text*/ begin += length + 1; @@ -4475,29 +4548,23 @@ static unsigned readChunk_iTXt(LodePNGInfo* info, const LodePNGDecompressSetting length = (unsigned)chunkLength < begin ? 0 : (unsigned)chunkLength - begin; if(compressed) { + unsigned char* str = 0; + size_t size = 0; /*will fail if zlib error, e.g. if length is too small*/ - error = zlib_decompress(&decoded.data, &decoded.size, - &data[begin], + error = zlib_decompress(&str, &size, 0, &data[begin], length, zlibsettings); - if(error) break; - if(decoded.allocsize < decoded.size) decoded.allocsize = decoded.size; - ucvector_push_back(&decoded, 0); + if(!error) error = lodepng_add_itext_sized(info, key, langtag, transkey, (char*)str, size); + lodepng_free(str); } else { - if(!ucvector_resize(&decoded, length + 1)) CERROR_BREAK(error, 83 /*alloc fail*/); - - decoded.data[length] = 0; - for(i = 0; i != length; ++i) decoded.data[i] = data[begin + i]; + error = lodepng_add_itext_sized(info, key, langtag, transkey, (char*)(data + begin), length); } - error = lodepng_add_itext(info, key, langtag, transkey, (char*)decoded.data); - break; } lodepng_free(key); lodepng_free(langtag); lodepng_free(transkey); - ucvector_cleanup(&decoded); return error; } @@ -4565,9 +4632,9 @@ static unsigned readChunk_iCCP(LodePNGInfo* info, const LodePNGDecompressSetting const unsigned char* data, size_t chunkLength) { unsigned error = 0; unsigned i; + size_t size = 0; unsigned length, string2_begin; - ucvector decoded; info->iccp_defined = 1; if(info->iccp_name) lodepng_clear_icc(info); @@ -4588,24 +4655,11 @@ static unsigned readChunk_iCCP(LodePNGInfo* info, const LodePNGDecompressSetting if(string2_begin > chunkLength) return 75; /*no null termination, corrupt?*/ length = (unsigned)chunkLength - string2_begin; - ucvector_init(&decoded); - error = zlib_decompress(&decoded.data, &decoded.size, + error = zlib_decompress(&info->iccp_profile, &size, 0, &data[string2_begin], length, zlibsettings); - if(!error) { - if(decoded.size) { - info->iccp_profile_size = (unsigned)decoded.size; - info->iccp_profile = (unsigned char*)lodepng_malloc(decoded.size); - if(info->iccp_profile) { - lodepng_memcpy(info->iccp_profile, decoded.data, decoded.size); - } else { - error = 83; /* alloc fail */ - } - } else { - error = 100; /*invalid ICC profile size*/ - } - } - ucvector_cleanup(&decoded); + info->iccp_profile_size = (unsigned)size; + if(!error && !info->iccp_profile_size) error = 100; /*invalid ICC profile size*/ return error; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ @@ -4618,7 +4672,7 @@ unsigned lodepng_inspect_chunk(LodePNGState* state, size_t pos, unsigned unhandled = 0; unsigned error = 0; - if (pos + 4 > insize) return 30; + if(pos + 4 > insize) return 30; chunkLength = lodepng_chunk_length(chunk); if(chunkLength > 2147483647) return 63; data = lodepng_chunk_data_const(chunk); @@ -4668,8 +4722,8 @@ static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, const unsigned char* in, size_t insize) { unsigned char IEND = 0; const unsigned char* chunk; - size_t i; - ucvector idat; /*the data from idat chunks*/ + unsigned char* idat; /*the data from idat chunks, zlib compressed*/ + size_t idatsize = 0; unsigned char* scanlines = 0; size_t scanlines_size = 0, expected_size = 0; size_t outsize = 0; @@ -4692,7 +4746,10 @@ static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, CERROR_RETURN(state->error, 92); /*overflow possible due to amount of pixels*/ } - ucvector_init(&idat); + /*the input filesize is a safe upper bound for the sum of idat chunks size*/ + idat = (unsigned char*)lodepng_malloc(insize); + if(!idat) CERROR_RETURN(state->error, 83); /*alloc fail*/ + chunk = &in[33]; /*first byte of the first chunk after the header*/ /*loop through the chunks, ignoring unknown chunks and stopping at IEND chunk. @@ -4725,11 +4782,11 @@ static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, /*IDAT chunk, containing compressed image data*/ if(lodepng_chunk_type_equals(chunk, "IDAT")) { - size_t oldsize = idat.size; size_t newsize; - if(lodepng_addofl(oldsize, chunkLength, &newsize)) CERROR_BREAK(state->error, 95); - if(!ucvector_resize(&idat, newsize)) CERROR_BREAK(state->error, 83 /*alloc fail*/); - for(i = 0; i != chunkLength; ++i) idat.data[oldsize + i] = data[i]; + if(lodepng_addofl(idatsize, chunkLength, &newsize)) CERROR_BREAK(state->error, 95); + if(newsize > insize) CERROR_BREAK(state->error, 95); + lodepng_memcpy(idat + idatsize, data, chunkLength); + idatsize += chunkLength; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS critical_pos = 3; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ @@ -4811,40 +4868,36 @@ static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, if(lodepng_chunk_check_crc(chunk)) CERROR_BREAK(state->error, 57); /*invalid CRC*/ } - if(!IEND) chunk = lodepng_chunk_next_const(chunk); + if(!IEND) chunk = lodepng_chunk_next_const(chunk, in + insize); } - /*predict output size, to allocate exact size for output buffer to avoid more dynamic allocation. - If the decompressed size does not match the prediction, the image must be corrupt.*/ - if(state->info_png.interlace_method == 0) { - expected_size = lodepng_get_raw_size_idat(*w, *h, &state->info_png.color); - } else { - /*Adam-7 interlaced: expected size is the sum of the 7 sub-images sizes*/ - const LodePNGColorMode* color = &state->info_png.color; - expected_size = 0; - expected_size += lodepng_get_raw_size_idat((*w + 7) >> 3, (*h + 7) >> 3, color); - if(*w > 4) expected_size += lodepng_get_raw_size_idat((*w + 3) >> 3, (*h + 7) >> 3, color); - expected_size += lodepng_get_raw_size_idat((*w + 3) >> 2, (*h + 3) >> 3, color); - if(*w > 2) expected_size += lodepng_get_raw_size_idat((*w + 1) >> 2, (*h + 3) >> 2, color); - expected_size += lodepng_get_raw_size_idat((*w + 1) >> 1, (*h + 1) >> 2, color); - if(*w > 1) expected_size += lodepng_get_raw_size_idat((*w + 0) >> 1, (*h + 1) >> 1, color); - expected_size += lodepng_get_raw_size_idat((*w + 0), (*h + 0) >> 1, color); + if(state->info_png.color.colortype == LCT_PALETTE && !state->info_png.color.palette) { + state->error = 106; /* error: PNG file must have PLTE chunk if color type is palette */ } + if(!state->error) { - /* This allocated data will be realloced by zlib_decompress, initially at - smaller size again. But the fact that it's already allocated at full size - here speeds the multiple reallocs up. TODO: make zlib_decompress support - receiving already allocated buffer with expected size instead. */ - scanlines = (unsigned char*)lodepng_malloc(expected_size); - if(!scanlines) state->error = 83; /*alloc fail*/ - scanlines_size = 0; + /*predict output size, to allocate exact size for output buffer to avoid more dynamic allocation. + If the decompressed size does not match the prediction, the image must be corrupt.*/ + if(state->info_png.interlace_method == 0) { + unsigned bpp = lodepng_get_bpp(&state->info_png.color); + expected_size = lodepng_get_raw_size_idat(*w, *h, bpp); + } else { + unsigned bpp = lodepng_get_bpp(&state->info_png.color); + /*Adam-7 interlaced: expected size is the sum of the 7 sub-images sizes*/ + expected_size = 0; + expected_size += lodepng_get_raw_size_idat((*w + 7) >> 3, (*h + 7) >> 3, bpp); + if(*w > 4) expected_size += lodepng_get_raw_size_idat((*w + 3) >> 3, (*h + 7) >> 3, bpp); + expected_size += lodepng_get_raw_size_idat((*w + 3) >> 2, (*h + 3) >> 3, bpp); + if(*w > 2) expected_size += lodepng_get_raw_size_idat((*w + 1) >> 2, (*h + 3) >> 2, bpp); + expected_size += lodepng_get_raw_size_idat((*w + 1) >> 1, (*h + 1) >> 2, bpp); + if(*w > 1) expected_size += lodepng_get_raw_size_idat((*w + 0) >> 1, (*h + 1) >> 1, bpp); + expected_size += lodepng_get_raw_size_idat((*w + 0), (*h + 0) >> 1, bpp); + } + + state->error = zlib_decompress(&scanlines, &scanlines_size, expected_size, idat, idatsize, &state->decoder.zlibsettings); } - if(!state->error) { - state->error = zlib_decompress(&scanlines, &scanlines_size, idat.data, - idat.size, &state->decoder.zlibsettings); - if(!state->error && scanlines_size != expected_size) state->error = 91; /*decompressed size doesn't match prediction*/ - } - ucvector_cleanup(&idat); + if(!state->error && scanlines_size != expected_size) state->error = 91; /*decompressed size doesn't match prediction*/ + lodepng_free(idat); if(!state->error) { outsize = lodepng_get_raw_size(*w, *h, &state->info_png.color); @@ -4852,7 +4905,7 @@ static void decodeGeneric(unsigned char** out, unsigned* w, unsigned* h, if(!*out) state->error = 83; /*alloc fail*/ } if(!state->error) { - for(i = 0; i < outsize; i++) (*out)[i] = 0; + lodepng_memset(*out, 0, outsize); state->error = postProcessScanlines(*out, scanlines, *w, *h, &state->info_png); } lodepng_free(scanlines); @@ -4872,8 +4925,7 @@ unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, state->error = lodepng_color_mode_copy(&state->info_raw, &state->info_png.color); if(state->error) return state->error; } - } else { - /*color conversion needed; sort of copy of the data*/ + } else { /*color conversion needed*/ unsigned char* data = *out; size_t outsize; @@ -4990,28 +5042,21 @@ void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source) { /* / PNG Encoder / */ /* ////////////////////////////////////////////////////////////////////////// */ -/*chunkName must be string of 4 characters*/ -static unsigned addChunk(ucvector* out, const char* chunkName, const unsigned char* data, size_t length) { - CERROR_TRY_RETURN(lodepng_chunk_create(&out->data, &out->size, (unsigned)length, chunkName, data)); - out->allocsize = out->size; /*fix the allocsize again*/ - return 0; -} -static void writeSignature(ucvector* out) { +static unsigned writeSignature(ucvector* out) { + size_t pos = out->size; + const unsigned char signature[] = {137, 80, 78, 71, 13, 10, 26, 10}; /*8 bytes PNG signature, aka the magic bytes*/ - ucvector_push_back(out, 137); - ucvector_push_back(out, 80); - ucvector_push_back(out, 78); - ucvector_push_back(out, 71); - ucvector_push_back(out, 13); - ucvector_push_back(out, 10); - ucvector_push_back(out, 26); - ucvector_push_back(out, 10); + if(!ucvector_resize(out, out->size + 8)) return 83; /*alloc fail*/ + lodepng_memcpy(out->data + pos, signature, 8); + return 0; } static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, LodePNGColorType colortype, unsigned bitdepth, unsigned interlace_method) { - unsigned char data[13]; + unsigned char *chunk, *data; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 13, "IHDR")); + data = chunk + 8; lodepng_set32bitInt(data + 0, w); /*width*/ lodepng_set32bitInt(data + 4, h); /*height*/ @@ -5021,244 +5066,267 @@ static unsigned addChunk_IHDR(ucvector* out, unsigned w, unsigned h, data[11] = 0; /*filter method*/ data[12] = interlace_method; /*interlace method*/ - return addChunk(out, "IHDR", data, sizeof(data)); + lodepng_chunk_generate_crc(chunk); + return 0; } +/* only adds the chunk if needed (there is a key or palette with alpha) */ static unsigned addChunk_PLTE(ucvector* out, const LodePNGColorMode* info) { - unsigned error = 0; - size_t i; - ucvector PLTE; - ucvector_init(&PLTE); - for(i = 0; i != info->palettesize * 4; ++i) { - /*add all channels except alpha channel*/ - if(i % 4 != 3) ucvector_push_back(&PLTE, info->palette[i]); - } - error = addChunk(out, "PLTE", PLTE.data, PLTE.size); - ucvector_cleanup(&PLTE); + unsigned char* chunk; + size_t i, j = 8; - return error; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, (unsigned)info->palettesize * 3, "PLTE")); + + for(i = 0; i != info->palettesize; ++i) { + /*add all channels except alpha channel*/ + chunk[j++] = info->palette[i * 4 + 0]; + chunk[j++] = info->palette[i * 4 + 1]; + chunk[j++] = info->palette[i * 4 + 2]; + } + + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_tRNS(ucvector* out, const LodePNGColorMode* info) { - unsigned error = 0; - size_t i; - ucvector tRNS; - ucvector_init(&tRNS); + unsigned char* chunk = 0; + if(info->colortype == LCT_PALETTE) { - size_t amount = info->palettesize; + size_t i, amount = info->palettesize; /*the tail of palette values that all have 255 as alpha, does not have to be encoded*/ for(i = info->palettesize; i != 0; --i) { - if(info->palette[4 * (i - 1) + 3] == 255) --amount; - else break; + if(info->palette[4 * (i - 1) + 3] != 255) break; + --amount; + } + if(amount) { + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, (unsigned)amount, "tRNS")); + /*add the alpha channel values from the palette*/ + for(i = 0; i != amount; ++i) chunk[8 + i] = info->palette[4 * i + 3]; } - /*add only alpha channel*/ - for(i = 0; i != amount; ++i) ucvector_push_back(&tRNS, info->palette[4 * i + 3]); } else if(info->colortype == LCT_GREY) { if(info->key_defined) { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r >> 8)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r & 255)); + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 2, "tRNS")); + chunk[8] = (unsigned char)(info->key_r >> 8); + chunk[9] = (unsigned char)(info->key_r & 255); } } else if(info->colortype == LCT_RGB) { if(info->key_defined) { - ucvector_push_back(&tRNS, (unsigned char)(info->key_r >> 8)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_r & 255)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g >> 8)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_g & 255)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b >> 8)); - ucvector_push_back(&tRNS, (unsigned char)(info->key_b & 255)); + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 6, "tRNS")); + chunk[8] = (unsigned char)(info->key_r >> 8); + chunk[9] = (unsigned char)(info->key_r & 255); + chunk[10] = (unsigned char)(info->key_g >> 8); + chunk[11] = (unsigned char)(info->key_g & 255); + chunk[12] = (unsigned char)(info->key_b >> 8); + chunk[13] = (unsigned char)(info->key_b & 255); } } - error = addChunk(out, "tRNS", tRNS.data, tRNS.size); - ucvector_cleanup(&tRNS); - - return error; + if(chunk) lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_IDAT(ucvector* out, const unsigned char* data, size_t datasize, LodePNGCompressSettings* zlibsettings) { - ucvector zlibdata; unsigned error = 0; + unsigned char* zlib = 0; + size_t zlibsize = 0; - /*compress with the Zlib compressor*/ - ucvector_init(&zlibdata); - error = zlib_compress(&zlibdata.data, &zlibdata.size, data, datasize, zlibsettings); - if(!error) error = addChunk(out, "IDAT", zlibdata.data, zlibdata.size); - ucvector_cleanup(&zlibdata); - + error = zlib_compress(&zlib, &zlibsize, data, datasize, zlibsettings); + if(!error) { + error = lodepng_chunk_createv(out, (unsigned)zlibsize, "IDAT", zlib); + } + lodepng_free(zlib); return error; } static unsigned addChunk_IEND(ucvector* out) { - unsigned error = 0; - error = addChunk(out, "IEND", 0, 0); - return error; + return lodepng_chunk_createv(out, 0, "IEND", 0); } #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS static unsigned addChunk_tEXt(ucvector* out, const char* keyword, const char* textstring) { - unsigned error = 0; - size_t i; - ucvector text; - ucvector_init(&text); - for(i = 0; keyword[i] != 0; ++i) ucvector_push_back(&text, (unsigned char)keyword[i]); - if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ - ucvector_push_back(&text, 0); /*0 termination char*/ - for(i = 0; textstring[i] != 0; ++i) ucvector_push_back(&text, (unsigned char)textstring[i]); - error = addChunk(out, "tEXt", text.data, text.size); - ucvector_cleanup(&text); - - return error; + unsigned char* chunk = 0; + size_t keysize = lodepng_strlen(keyword), textsize = lodepng_strlen(textstring); + size_t size = keysize + 1 + textsize; + if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, (unsigned)size, "tEXt")); + lodepng_memcpy(chunk + 8, keyword, keysize); + chunk[8 + keysize] = 0; /*null termination char*/ + lodepng_memcpy(chunk + 9 + keysize, textstring, textsize); + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_zTXt(ucvector* out, const char* keyword, const char* textstring, LodePNGCompressSettings* zlibsettings) { unsigned error = 0; - ucvector data, compressed; - size_t i, textsize = lodepng_strlen(textstring); + unsigned char* chunk = 0; + unsigned char* compressed = 0; + size_t compressedsize = 0; + size_t textsize = lodepng_strlen(textstring); + size_t keysize = lodepng_strlen(keyword); + if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - ucvector_init(&data); - ucvector_init(&compressed); - for(i = 0; keyword[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)keyword[i]); - if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ - ucvector_push_back(&data, 0); /*0 termination char*/ - ucvector_push_back(&data, 0); /*compression method: 0*/ - - error = zlib_compress(&compressed.data, &compressed.size, + error = zlib_compress(&compressed, &compressedsize, (const unsigned char*)textstring, textsize, zlibsettings); if(!error) { - for(i = 0; i != compressed.size; ++i) ucvector_push_back(&data, compressed.data[i]); - error = addChunk(out, "zTXt", data.data, data.size); + size_t size = keysize + 2 + compressedsize; + error = lodepng_chunk_init(&chunk, out, (unsigned)size, "zTXt"); + } + if(!error) { + lodepng_memcpy(chunk + 8, keyword, keysize); + chunk[8 + keysize] = 0; /*null termination char*/ + chunk[9 + keysize] = 0; /*compression method: 0*/ + lodepng_memcpy(chunk + 10 + keysize, compressed, compressedsize); + lodepng_chunk_generate_crc(chunk); } - ucvector_cleanup(&compressed); - ucvector_cleanup(&data); + lodepng_free(compressed); return error; } -static unsigned addChunk_iTXt(ucvector* out, unsigned compressed, const char* keyword, const char* langtag, +static unsigned addChunk_iTXt(ucvector* out, unsigned compress, const char* keyword, const char* langtag, const char* transkey, const char* textstring, LodePNGCompressSettings* zlibsettings) { unsigned error = 0; - ucvector data; - size_t i, textsize = lodepng_strlen(textstring); + unsigned char* chunk = 0; + unsigned char* compressed = 0; + size_t compressedsize = 0; + size_t textsize = lodepng_strlen(textstring); + size_t keysize = lodepng_strlen(keyword), langsize = lodepng_strlen(langtag), transsize = lodepng_strlen(transkey); - ucvector_init(&data); + if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ - for(i = 0; keyword[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)keyword[i]); - if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ - ucvector_push_back(&data, 0); /*null termination char*/ - ucvector_push_back(&data, compressed ? 1 : 0); /*compression flag*/ - ucvector_push_back(&data, 0); /*compression method*/ - for(i = 0; langtag[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)langtag[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - for(i = 0; transkey[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)transkey[i]); - ucvector_push_back(&data, 0); /*null termination char*/ - - if(compressed) { - ucvector compressed_data; - ucvector_init(&compressed_data); - error = zlib_compress(&compressed_data.data, &compressed_data.size, + if(compress) { + error = zlib_compress(&compressed, &compressedsize, (const unsigned char*)textstring, textsize, zlibsettings); - if(!error) { - for(i = 0; i != compressed_data.size; ++i) ucvector_push_back(&data, compressed_data.data[i]); + } + if(!error) { + size_t size = keysize + 3 + langsize + 1 + transsize + 1 + (compress ? compressedsize : textsize); + error = lodepng_chunk_init(&chunk, out, (unsigned)size, "iTXt"); + } + if(!error) { + size_t pos = 8; + lodepng_memcpy(chunk + pos, keyword, keysize); + pos += keysize; + chunk[pos++] = 0; /*null termination char*/ + chunk[pos++] = (compress ? 1 : 0); /*compression flag*/ + chunk[pos++] = 0; /*compression method: 0*/ + lodepng_memcpy(chunk + pos, langtag, langsize); + pos += langsize; + chunk[pos++] = 0; /*null termination char*/ + lodepng_memcpy(chunk + pos, transkey, transsize); + pos += transsize; + chunk[pos++] = 0; /*null termination char*/ + if(compress) { + lodepng_memcpy(chunk + pos, compressed, compressedsize); + } else { + lodepng_memcpy(chunk + pos, textstring, textsize); } - ucvector_cleanup(&compressed_data); - } else /*not compressed*/ { - for(i = 0; textstring[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)textstring[i]); + lodepng_chunk_generate_crc(chunk); } - if(!error) error = addChunk(out, "iTXt", data.data, data.size); - ucvector_cleanup(&data); + lodepng_free(compressed); return error; } static unsigned addChunk_bKGD(ucvector* out, const LodePNGInfo* info) { - unsigned char data[6]; - size_t size = 0; + unsigned char* chunk = 0; if(info->color.colortype == LCT_GREY || info->color.colortype == LCT_GREY_ALPHA) { - data[0] = (unsigned char)(info->background_r >> 8); - data[1] = (unsigned char)(info->background_r & 255); - size = 2; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 2, "bKGD")); + chunk[8] = (unsigned char)(info->background_r >> 8); + chunk[9] = (unsigned char)(info->background_r & 255); } else if(info->color.colortype == LCT_RGB || info->color.colortype == LCT_RGBA) { - data[0] = (unsigned char)(info->background_r >> 8); - data[1] = (unsigned char)(info->background_r & 255); - data[2] = (unsigned char)(info->background_g >> 8); - data[3] = (unsigned char)(info->background_g & 255); - data[4] = (unsigned char)(info->background_b >> 8); - data[5] = (unsigned char)(info->background_b & 255); - size = 6; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 6, "bKGD")); + chunk[8] = (unsigned char)(info->background_r >> 8); + chunk[9] = (unsigned char)(info->background_r & 255); + chunk[10] = (unsigned char)(info->background_g >> 8); + chunk[11] = (unsigned char)(info->background_g & 255); + chunk[12] = (unsigned char)(info->background_b >> 8); + chunk[13] = (unsigned char)(info->background_b & 255); } else if(info->color.colortype == LCT_PALETTE) { - data[0] =(unsigned char)(info->background_r & 255); /*palette index*/ - size = 1; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 1, "bKGD")); + chunk[8] = (unsigned char)(info->background_r & 255); /*palette index*/ } - return addChunk(out, "bKGD", data, size); + if(chunk) lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_tIME(ucvector* out, const LodePNGTime* time) { - unsigned char data[7]; - data[0] = (unsigned char)(time->year >> 8); - data[1] = (unsigned char)(time->year & 255); - data[2] = (unsigned char)time->month; - data[3] = (unsigned char)time->day; - data[4] = (unsigned char)time->hour; - data[5] = (unsigned char)time->minute; - data[6] = (unsigned char)time->second; - return addChunk(out, "tIME", data, sizeof(data)); + unsigned char* chunk; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 7, "tIME")); + chunk[8] = (unsigned char)(time->year >> 8); + chunk[9] = (unsigned char)(time->year & 255); + chunk[10] = (unsigned char)time->month; + chunk[11] = (unsigned char)time->day; + chunk[12] = (unsigned char)time->hour; + chunk[13] = (unsigned char)time->minute; + chunk[14] = (unsigned char)time->second; + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_pHYs(ucvector* out, const LodePNGInfo* info) { - unsigned char data[9]; - lodepng_set32bitInt(data + 0, info->phys_x); - lodepng_set32bitInt(data + 4, info->phys_y); data[8] = info->phys_unit; - return addChunk(out, "pHYs", data, sizeof(data)); + unsigned char* chunk; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 9, "pHYs")); + lodepng_set32bitInt(chunk + 8, info->phys_x); + lodepng_set32bitInt(chunk + 12, info->phys_y); + chunk[16] = info->phys_unit; + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_gAMA(ucvector* out, const LodePNGInfo* info) { - unsigned char data[4]; - lodepng_set32bitInt(data, info->gama_gamma); - return addChunk(out, "gAMA", data, sizeof(data)); + unsigned char* chunk; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 4, "gAMA")); + lodepng_set32bitInt(chunk + 8, info->gama_gamma); + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_cHRM(ucvector* out, const LodePNGInfo* info) { - unsigned char data[32]; - lodepng_set32bitInt(data + 0, info->chrm_white_x); - lodepng_set32bitInt(data + 4, info->chrm_white_y); - lodepng_set32bitInt(data + 8, info->chrm_red_x); - lodepng_set32bitInt(data + 12, info->chrm_red_y); - lodepng_set32bitInt(data + 16, info->chrm_green_x); - lodepng_set32bitInt(data + 20, info->chrm_green_y); - lodepng_set32bitInt(data + 24, info->chrm_blue_x); - lodepng_set32bitInt(data + 28, info->chrm_blue_y); - return addChunk(out, "cHRM", data, sizeof(data)); + unsigned char* chunk; + CERROR_TRY_RETURN(lodepng_chunk_init(&chunk, out, 32, "cHRM")); + lodepng_set32bitInt(chunk + 8, info->chrm_white_x); + lodepng_set32bitInt(chunk + 12, info->chrm_white_y); + lodepng_set32bitInt(chunk + 16, info->chrm_red_x); + lodepng_set32bitInt(chunk + 20, info->chrm_red_y); + lodepng_set32bitInt(chunk + 24, info->chrm_green_x); + lodepng_set32bitInt(chunk + 28, info->chrm_green_y); + lodepng_set32bitInt(chunk + 32, info->chrm_blue_x); + lodepng_set32bitInt(chunk + 36, info->chrm_blue_y); + lodepng_chunk_generate_crc(chunk); + return 0; } static unsigned addChunk_sRGB(ucvector* out, const LodePNGInfo* info) { unsigned char data = info->srgb_intent; - return addChunk(out, "sRGB", &data, 1); + return lodepng_chunk_createv(out, 1, "sRGB", &data); } static unsigned addChunk_iCCP(ucvector* out, const LodePNGInfo* info, LodePNGCompressSettings* zlibsettings) { unsigned error = 0; - ucvector data, compressed; - size_t i; + unsigned char* chunk = 0; + unsigned char* compressed = 0; + size_t compressedsize = 0; + size_t keysize = lodepng_strlen(info->iccp_name); - ucvector_init(&data); - ucvector_init(&compressed); - for(i = 0; info->iccp_name[i] != 0; ++i) ucvector_push_back(&data, (unsigned char)info->iccp_name[i]); - if(i < 1 || i > 79) return 89; /*error: invalid keyword size*/ - ucvector_push_back(&data, 0); /*0 termination char*/ - ucvector_push_back(&data, 0); /*compression method: 0*/ - - error = zlib_compress(&compressed.data, &compressed.size, + if(keysize < 1 || keysize > 79) return 89; /*error: invalid keyword size*/ + error = zlib_compress(&compressed, &compressedsize, info->iccp_profile, info->iccp_profile_size, zlibsettings); if(!error) { - for(i = 0; i != compressed.size; ++i) ucvector_push_back(&data, compressed.data[i]); - error = addChunk(out, "iCCP", data.data, data.size); + size_t size = keysize + 2 + compressedsize; + error = lodepng_chunk_init(&chunk, out, (unsigned)size, "iCCP"); + } + if(!error) { + lodepng_memcpy(chunk + 8, info->iccp_name, keysize); + chunk[8 + keysize] = 0; /*null termination char*/ + chunk[9 + keysize] = 0; /*compression method: 0*/ + lodepng_memcpy(chunk + 10 + keysize, compressed, compressedsize); + lodepng_chunk_generate_crc(chunk); } - ucvector_cleanup(&compressed); - ucvector_cleanup(&data); + lodepng_free(compressed); return error; } @@ -5304,31 +5372,43 @@ static void filterScanline(unsigned char* out, const unsigned char* scanline, co for(i = bytewidth; i < length; ++i) out[i] = (scanline[i] - scanline[i - bytewidth]); } break; - default: return; /*nonexistent filter type given*/ + default: return; /*invalid filter type given*/ } } -/* integer binary logarithm */ +/* integer binary logarithm, max return value is 31 */ static size_t ilog2(size_t i) { size_t result = 0; - while(i >= 65536) { result += 16; i >>= 16; } - while(i >= 256) { result += 8; i >>= 8; } - while(i >= 16) { result += 4; i >>= 4; } - while(i >= 2) { result += 1; i >>= 1; } + if(i >= 65536) { result += 16; i >>= 16; } + if(i >= 256) { result += 8; i >>= 8; } + if(i >= 16) { result += 4; i >>= 4; } + if(i >= 4) { result += 2; i >>= 2; } + if(i >= 2) { result += 1; /*i >>= 1;*/ } return result; } +/* integer approximation for i * log2(i), helper function for LFS_ENTROPY */ +static size_t ilog2i(size_t i) { + size_t l; + if(i == 0) return 0; + l = ilog2(i); + /* approximate i*log2(i): l is integer logarithm, ((i - (1u << l)) << 1u) + linearly approximates the missing fractional part multiplied by i */ + return i * l + ((i - ((size_t) 1u << l)) << 1u); +} + static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, unsigned h, - const LodePNGColorMode* info, const LodePNGEncoderSettings* settings) { + const LodePNGColorMode* color, const LodePNGEncoderSettings* settings) { /* For PNG filter method 0 out must be a buffer with as size: h + (w * h * bpp + 7u) / 8u, because there are the scanlines with 1 extra byte per scanline */ - unsigned bpp = lodepng_get_bpp(info); + unsigned bpp = lodepng_get_bpp(color); /*the width of a scanline in bytes, not including the filter type*/ - size_t linebytes = (w * bpp + 7u) / 8u; + size_t linebytes = lodepng_get_raw_size_idat(w, 1, bpp) - 1u; + /*bytewidth is used for filtering, is 1 when bpp < 8, number of bytes per pixel otherwise*/ size_t bytewidth = (bpp + 7u) / 8u; const unsigned char* prevline = 0; @@ -5350,7 +5430,7 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, heuristic is used. */ if(settings->filter_palette_zero && - (info->colortype == LCT_PALETTE || info->bitdepth < 8)) strategy = LFS_ZERO; + (color->colortype == LCT_PALETTE || color->bitdepth < 8)) strategy = LFS_ZERO; if(bpp == 0) return 31; /*error: invalid color type*/ @@ -5365,40 +5445,39 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, } } else if(strategy == LFS_MINSUM) { /*adaptive filtering*/ - size_t sum[5]; unsigned char* attempt[5]; /*five filtering attempts, one for each filter type*/ size_t smallest = 0; unsigned char type, bestType = 0; for(type = 0; type != 5; ++type) { attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) return 83; /*alloc fail*/ + if(!attempt[type]) error = 83; /*alloc fail*/ } if(!error) { for(y = 0; y != h; ++y) { /*try the 5 filter types*/ for(type = 0; type != 5; ++type) { + size_t sum = 0; filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); /*calculate the sum of the result*/ - sum[type] = 0; if(type == 0) { - for(x = 0; x != linebytes; ++x) sum[type] += (unsigned char)(attempt[type][x]); + for(x = 0; x != linebytes; ++x) sum += (unsigned char)(attempt[type][x]); } else { for(x = 0; x != linebytes; ++x) { /*For differences, each byte should be treated as signed, values above 127 are negative (converted to signed char). Filtertype 0 isn't a difference though, so use unsigned there. This means filtertype 0 is almost never chosen, but that is justified.*/ unsigned char s = attempt[type][x]; - sum[type] += s < 128 ? s : (255U - s); + sum += s < 128 ? s : (255U - s); } } /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || sum[type] < smallest) { + if(type == 0 || sum < smallest) { bestType = type; - smallest = sum[type]; + smallest = sum; } } @@ -5412,7 +5491,6 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); } else if(strategy == LFS_ENTROPY) { - size_t sum[5]; unsigned char* attempt[5]; /*five filtering attempts, one for each filter type*/ size_t bestSum = 0; unsigned type, bestType = 0; @@ -5420,32 +5498,34 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, for(type = 0; type != 5; ++type) { attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) return 83; /*alloc fail*/ + if(!attempt[type]) error = 83; /*alloc fail*/ } - for(y = 0; y != h; ++y) { - /*try the 5 filter types*/ - for(type = 0; type != 5; ++type) { - filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); - for(x = 0; x != 256; ++x) count[x] = 0; - for(x = 0; x != linebytes; ++x) ++count[attempt[type][x]]; - ++count[type]; /*the filter type itself is part of the scanline*/ - sum[type] = 0; - for(x = 0; x != 256; ++x) { - sum[type] += count[x] == 0 ? 0 : ilog2(count[x]) * count[x]; - } - /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || sum[type] > bestSum) { - bestType = type; - bestSum = sum[type]; + if(!error) { + for(y = 0; y != h; ++y) { + /*try the 5 filter types*/ + for(type = 0; type != 5; ++type) { + size_t sum = 0; + filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); + lodepng_memset(count, 0, 256 * sizeof(*count)); + for(x = 0; x != linebytes; ++x) ++count[attempt[type][x]]; + ++count[type]; /*the filter type itself is part of the scanline*/ + for(x = 0; x != 256; ++x) { + sum += ilog2i(count[x]); + } + /*check if this is smallest sum (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || sum > bestSum) { + bestType = type; + bestSum = sum; + } } + + prevline = &in[y * linebytes]; + + /*now fill the out values*/ + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x != linebytes; ++x) out[y * (linebytes + 1) + 1 + x] = attempt[bestType][x]; } - - prevline = &in[y * linebytes]; - - /*now fill the out values*/ - out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ - for(x = 0; x != linebytes; ++x) out[y * (linebytes + 1) + 1 + x] = attempt[bestType][x]; } for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); @@ -5467,7 +5547,8 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, size_t smallest = 0; unsigned type = 0, bestType = 0; unsigned char* dummy; - LodePNGCompressSettings zlibsettings = settings->zlibsettings; + LodePNGCompressSettings zlibsettings; + lodepng_memcpy(&zlibsettings, &settings->zlibsettings, sizeof(LodePNGCompressSettings)); /*use fixed tree on the attempts so that the tree is not adapted to the filtertype on purpose, to simulate the true case where the tree is the same for the whole image. Sometimes it gives better result with dynamic tree anyway. Using the fixed tree sometimes gives worse, but in rare @@ -5479,27 +5560,29 @@ static unsigned filter(unsigned char* out, const unsigned char* in, unsigned w, zlibsettings.custom_deflate = 0; for(type = 0; type != 5; ++type) { attempt[type] = (unsigned char*)lodepng_malloc(linebytes); - if(!attempt[type]) return 83; /*alloc fail*/ + if(!attempt[type]) error = 83; /*alloc fail*/ } - for(y = 0; y != h; ++y) /*try the 5 filter types*/ { - for(type = 0; type != 5; ++type) { - unsigned testsize = (unsigned)linebytes; - /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ + if(!error) { + for(y = 0; y != h; ++y) /*try the 5 filter types*/ { + for(type = 0; type != 5; ++type) { + unsigned testsize = (unsigned)linebytes; + /*if(testsize > 8) testsize /= 8;*/ /*it already works good enough by testing a part of the row*/ - filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); - size[type] = 0; - dummy = 0; - zlib_compress(&dummy, &size[type], attempt[type], testsize, &zlibsettings); - lodepng_free(dummy); - /*check if this is smallest size (or if type == 0 it's the first case so always store the values)*/ - if(type == 0 || size[type] < smallest) { - bestType = type; - smallest = size[type]; + filterScanline(attempt[type], &in[y * linebytes], prevline, linebytes, bytewidth, type); + size[type] = 0; + dummy = 0; + zlib_compress(&dummy, &size[type], attempt[type], testsize, &zlibsettings); + lodepng_free(dummy); + /*check if this is smallest size (or if type == 0 it's the first case so always store the values)*/ + if(type == 0 || size[type] < smallest) { + bestType = type; + smallest = size[type]; + } } + prevline = &in[y * linebytes]; + out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ + for(x = 0; x != linebytes; ++x) out[y * (linebytes + 1) + 1 + x] = attempt[bestType][x]; } - prevline = &in[y * linebytes]; - out[y * (linebytes + 1)] = bestType; /*the first byte of a scanline will be the filter type*/ - for(x = 0; x != linebytes; ++x) out[y * (linebytes + 1) + 1 + x] = attempt[bestType][x]; } for(type = 0; type != 5; ++type) lodepng_free(attempt[type]); } @@ -5652,36 +5735,13 @@ static unsigned preProcessScanlines(unsigned char** out, size_t* outsize, const return error; } -/* -palette must have 4 * palettesize bytes allocated, and given in format RGBARGBARGBARGBA... -returns 0 if the palette is opaque, -returns 1 if the palette has a single color with alpha 0 ==> color key -returns 2 if the palette is semi-translucent. -*/ -static unsigned getPaletteTranslucency(const unsigned char* palette, size_t palettesize) { - size_t i; - unsigned key = 0; - unsigned r = 0, g = 0, b = 0; /*the value of the color with alpha 0, so long as color keying is possible*/ - for(i = 0; i != palettesize; ++i) { - if(!key && palette[4 * i + 3] == 0) { - r = palette[4 * i + 0]; g = palette[4 * i + 1]; b = palette[4 * i + 2]; - key = 1; - i = (size_t)(-1); /*restart from beginning, to detect earlier opaque colors with key's value*/ - } - else if(palette[4 * i + 3] != 255) return 2; - /*when key, no opaque RGB may have key's RGB*/ - else if(key && r == palette[i * 4 + 0] && g == palette[i * 4 + 1] && b == palette[i * 4 + 2]) return 2; - } - return key; -} - #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS static unsigned addUnknownChunks(ucvector* out, unsigned char* data, size_t datasize) { unsigned char* inchunk = data; while((size_t)(inchunk - data) < datasize) { CERROR_TRY_RETURN(lodepng_chunk_append(&out->data, &out->size, inchunk)); out->allocsize = out->size; /*fix the allocsize again*/ - inchunk = lodepng_chunk_next(inchunk); + inchunk = lodepng_chunk_next(inchunk, data + datasize); } return 0; } @@ -5712,11 +5772,10 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, LodePNGState* state) { unsigned char* data = 0; /*uncompressed version of the IDAT chunk data*/ size_t datasize = 0; - ucvector outv; + ucvector outv = ucvector_init(NULL, 0); LodePNGInfo info; const LodePNGInfo* info_png = &state->info_png; - ucvector_init(&outv); lodepng_info_init(&info); /*provide some proper output values if error will happen*/ @@ -5731,17 +5790,17 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, goto cleanup; } if(state->encoder.zlibsettings.btype > 2) { - state->error = 61; /*error: nonexistent btype*/ + state->error = 61; /*error: invalid btype*/ goto cleanup; } if(info_png->interlace_method > 1) { - state->error = 71; /*error: nonexistent interlace mode*/ + state->error = 71; /*error: invalid interlace mode*/ goto cleanup; } state->error = checkColorValidity(info_png->color.colortype, info_png->color.bitdepth); - if(state->error) goto cleanup; /*error: nonexistent color type given*/ + if(state->error) goto cleanup; /*error: invalid color type given*/ state->error = checkColorValidity(state->info_raw.colortype, state->info_raw.bitdepth); - if(state->error) goto cleanup; /*error: nonexistent color type given*/ + if(state->error) goto cleanup; /*error: invalid color type given*/ /* color convert and compute scanline filter types */ lodepng_info_copy(&info, &state->info_png); @@ -5761,14 +5820,16 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, stats.allow_greyscale = 0; } #endif /* LODEPNG_COMPILE_ANCILLARY_CHUNKS */ - lodepng_compute_color_stats(&stats, image, w, h, &state->info_raw); + state->error = lodepng_compute_color_stats(&stats, image, w, h, &state->info_raw); + if(state->error) goto cleanup; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS if(info_png->background_defined) { /*the background chunk's color must be taken into account as well*/ unsigned r = 0, g = 0, b = 0; LodePNGColorMode mode16 = lodepng_color_mode_make(LCT_RGB, 16); lodepng_convert_rgb(&r, &g, &b, info_png->background_r, info_png->background_g, info_png->background_b, &mode16, &info_png->color); - lodepng_color_stats_add(&stats, r, g, b, 65535); + state->error = lodepng_color_stats_add(&stats, r, g, b, 65535); + if(state->error) goto cleanup; } #endif /* LODEPNG_COMPILE_ANCILLARY_CHUNKS */ state->error = auto_choose_color(&info.color, &state->info_raw, &stats); @@ -5810,20 +5871,26 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, if(!state->error) { state->error = lodepng_convert(converted, image, &info.color, &state->info_raw, w, h); } - if(!state->error) preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); + if(!state->error) { + state->error = preProcessScanlines(&data, &datasize, converted, w, h, &info, &state->encoder); + } lodepng_free(converted); if(state->error) goto cleanup; + } else { + state->error = preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); + if(state->error) goto cleanup; } - else preProcessScanlines(&data, &datasize, image, w, h, &info, &state->encoder); /* output all PNG chunks */ { #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS size_t i; #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /*write signature and chunks*/ - writeSignature(&outv); + state->error = writeSignature(&outv); + if(state->error) goto cleanup; /*IHDR*/ - addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); + state->error = addChunk_IHDR(&outv, w, h, info.color.colortype, info.color.bitdepth, info.interlace_method); + if(state->error) goto cleanup; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*unknown chunks between IHDR and PLTE*/ if(info.unknown_chunks_data[0]) { @@ -5831,25 +5898,36 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, if(state->error) goto cleanup; } /*color profile chunks must come before PLTE */ - if(info.iccp_defined) addChunk_iCCP(&outv, &info, &state->encoder.zlibsettings); - if(info.srgb_defined) addChunk_sRGB(&outv, &info); - if(info.gama_defined) addChunk_gAMA(&outv, &info); - if(info.chrm_defined) addChunk_cHRM(&outv, &info); + if(info.iccp_defined) { + state->error = addChunk_iCCP(&outv, &info, &state->encoder.zlibsettings); + if(state->error) goto cleanup; + } + if(info.srgb_defined) { + state->error = addChunk_sRGB(&outv, &info); + if(state->error) goto cleanup; + } + if(info.gama_defined) { + state->error = addChunk_gAMA(&outv, &info); + if(state->error) goto cleanup; + } + if(info.chrm_defined) { + state->error = addChunk_cHRM(&outv, &info); + if(state->error) goto cleanup; + } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ /*PLTE*/ if(info.color.colortype == LCT_PALETTE) { - addChunk_PLTE(&outv, &info.color); + state->error = addChunk_PLTE(&outv, &info.color); + if(state->error) goto cleanup; } if(state->encoder.force_palette && (info.color.colortype == LCT_RGB || info.color.colortype == LCT_RGBA)) { - addChunk_PLTE(&outv, &info.color); - } - /*tRNS*/ - if(info.color.colortype == LCT_PALETTE && getPaletteTranslucency(info.color.palette, info.color.palettesize) != 0) { - addChunk_tRNS(&outv, &info.color); - } - if((info.color.colortype == LCT_GREY || info.color.colortype == LCT_RGB) && info.color.key_defined) { - addChunk_tRNS(&outv, &info.color); + /*force_palette means: write suggested palette for truecolor in PLTE chunk*/ + state->error = addChunk_PLTE(&outv, &info.color); + if(state->error) goto cleanup; } + /*tRNS (this will only add if when necessary) */ + state->error = addChunk_tRNS(&outv, &info.color); + if(state->error) goto cleanup; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*bKGD (must come between PLTE and the IDAt chunks*/ if(info.background_defined) { @@ -5857,7 +5935,10 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, if(state->error) goto cleanup; } /*pHYs (must come before the IDAT chunks)*/ - if(info.phys_defined) addChunk_pHYs(&outv, &info); + if(info.phys_defined) { + state->error = addChunk_pHYs(&outv, &info); + if(state->error) goto cleanup; + } /*unknown chunks between PLTE and IDAT*/ if(info.unknown_chunks_data[1]) { @@ -5870,7 +5951,10 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, if(state->error) goto cleanup; #ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS /*tIME*/ - if(info.time_defined) addChunk_tIME(&outv, &info.time); + if(info.time_defined) { + state->error = addChunk_tIME(&outv, &info.time); + if(state->error) goto cleanup; + } /*tEXt and/or zTXt*/ for(i = 0; i != info.text_num; ++i) { if(lodepng_strlen(info.text_keys[i]) > 79) { @@ -5882,9 +5966,11 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, goto cleanup; } if(state->encoder.text_compression) { - addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); + state->error = addChunk_zTXt(&outv, info.text_keys[i], info.text_strings[i], &state->encoder.zlibsettings); + if(state->error) goto cleanup; } else { - addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); + state->error = addChunk_tEXt(&outv, info.text_keys[i], info.text_strings[i]); + if(state->error) goto cleanup; } } /*LodePNG version id in text chunk*/ @@ -5900,7 +5986,8 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, } } if(already_added_id_text == 0) { - addChunk_tEXt(&outv, "LodePNG", LODEPNG_VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ + state->error = addChunk_tEXt(&outv, "LodePNG", LODEPNG_VERSION_STRING); /*it's shorter as tEXt than as zTXt chunk*/ + if(state->error) goto cleanup; } } /*iTXt*/ @@ -5913,9 +6000,11 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, state->error = 67; /*text chunk too small*/ goto cleanup; } - addChunk_iTXt(&outv, state->encoder.text_compression, - info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], - &state->encoder.zlibsettings); + state->error = addChunk_iTXt( + &outv, state->encoder.text_compression, + info.itext_keys[i], info.itext_langtags[i], info.itext_transkeys[i], info.itext_strings[i], + &state->encoder.zlibsettings); + if(state->error) goto cleanup; } /*unknown chunks between IDAT and IEND*/ @@ -5924,7 +6013,8 @@ unsigned lodepng_encode(unsigned char** out, size_t* outsize, if(state->error) goto cleanup; } #endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - addChunk_IEND(&outv); + state->error = addChunk_IEND(&outv); + if(state->error) goto cleanup; } cleanup: @@ -6011,7 +6101,8 @@ const char* lodepng_error_text(unsigned code) { case 13: return "problem while processing dynamic deflate block"; case 14: return "problem while processing dynamic deflate block"; case 15: return "problem while processing dynamic deflate block"; - case 16: return "nonexistent code while processing dynamic deflate block"; + /*this error could happen if there are only 0 or 1 symbols present in the huffman code:*/ + case 16: return "invalid code while processing dynamic deflate block"; case 17: return "end of out buffer memory reached while inflating"; case 18: return "invalid distance code while inflating"; case 19: return "end of out buffer memory reached while inflating"; @@ -6074,8 +6165,8 @@ const char* lodepng_error_text(unsigned code) { case 67: return "the length of a text chunk keyword given to the encoder is smaller than the minimum of 1 byte"; case 68: return "tried to encode a PLTE chunk with a palette that has less than 1 or more than 256 colors"; case 69: return "unknown chunk type with 'critical' flag encountered by the decoder"; - case 71: return "nonexistent interlace mode given to encoder (must be 0 or 1)"; - case 72: return "while decoding, nonexistent compression method encountering in zTXt or iTXt chunk (it must be 0)"; + case 71: return "invalid interlace mode given to encoder (must be 0 or 1)"; + case 72: return "while decoding, invalid compression method encountering in zTXt or iTXt chunk (it must be 0)"; case 73: return "invalid tIME chunk size"; case 74: return "invalid pHYs chunk size"; /*length could be wrong, or data chopped off*/ @@ -6110,6 +6201,9 @@ const char* lodepng_error_text(unsigned code) { case 103: return "invalid palette index in bKGD chunk. Maybe it came before PLTE chunk?"; case 104: return "invalid bKGD color while encoding (e.g. palette index out of range)"; case 105: return "integer overflow of bitsize"; + case 106: return "PNG file must have PLTE chunk if color type is palette"; + case 107: return "color convert from palette mode requested without setting the palette data in it"; + case 108: return "tried to add more than 256 values to a palette"; } return "unknown error code"; } @@ -6144,7 +6238,7 @@ unsigned decompress(std::vector& out, const unsigned char* in, si const LodePNGDecompressSettings& settings) { unsigned char* buffer = 0; size_t buffersize = 0; - unsigned error = zlib_decompress(&buffer, &buffersize, in, insize, &settings); + unsigned error = zlib_decompress(&buffer, &buffersize, 0, in, insize, &settings); if(buffer) { out.insert(out.end(), &buffer[0], &buffer[buffersize]); lodepng_free(buffer); @@ -6203,7 +6297,7 @@ State& State::operator=(const State& other) { unsigned decode(std::vector& out, unsigned& w, unsigned& h, const unsigned char* in, size_t insize, LodePNGColorType colortype, unsigned bitdepth) { - unsigned char* buffer; + unsigned char* buffer = 0; unsigned error = lodepng_decode_memory(&buffer, &w, &h, in, insize, colortype, bitdepth); if(buffer && !error) { State state; @@ -6211,8 +6305,8 @@ unsigned decode(std::vector& out, unsigned& w, unsigned& h, const state.info_raw.bitdepth = bitdepth; size_t buffersize = lodepng_get_raw_size(w, h, &state.info_raw); out.insert(out.end(), &buffer[0], &buffer[buffersize]); - lodepng_free(buffer); } + lodepng_free(buffer); return error; } diff --git a/app/src/main/cpp/core/lodepng.h b/app/src/main/cpp/core/lodepng.h index 6f09353..a386459 100644 --- a/app/src/main/cpp/core/lodepng.h +++ b/app/src/main/cpp/core/lodepng.h @@ -1,1953 +1,1945 @@ -/* -LodePNG version 20190914 - -Copyright (c) 2005-2019 Lode Vandevenne - -This software is provided 'as-is', without any express or implied -warranty. In no event will the authors be held liable for any damages -arising from the use of this software. - -Permission is granted to anyone to use this software for any purpose, -including commercial applications, and to alter it and redistribute it -freely, subject to the following restrictions: - - 1. The origin of this software must not be misrepresented; you must not - claim that you wrote the original software. If you use this software - in a product, an acknowledgment in the product documentation would be - appreciated but is not required. - - 2. Altered source versions must be plainly marked as such, and must not be - misrepresented as being the original software. - - 3. This notice may not be removed or altered from any source - distribution. -*/ - -#ifndef LODEPNG_H -#define LODEPNG_H - -#include /*for size_t*/ - -extern const char* LODEPNG_VERSION_STRING; - -/* -The following #defines are used to create code sections. They can be disabled -to disable code sections, which can give faster compile time and smaller binary. -The "NO_COMPILE" defines are designed to be used to pass as defines to the -compiler command to disable them without modifying this header, e.g. --DLODEPNG_NO_COMPILE_ZLIB for gcc. -In addition to those below, you can also define LODEPNG_NO_COMPILE_CRC to -allow implementing a custom lodepng_crc32. -*/ -/*deflate & zlib. If disabled, you must specify alternative zlib functions in -the custom_zlib field of the compress and decompress settings*/ -#ifndef LODEPNG_NO_COMPILE_ZLIB -#define LODEPNG_COMPILE_ZLIB -#endif - -/*png encoder and png decoder*/ -#ifndef LODEPNG_NO_COMPILE_PNG -#define LODEPNG_COMPILE_PNG -#endif - -/*deflate&zlib decoder and png decoder*/ -#ifndef LODEPNG_NO_COMPILE_DECODER -#define LODEPNG_COMPILE_DECODER -#endif - -/*deflate&zlib encoder and png encoder*/ -#ifndef LODEPNG_NO_COMPILE_ENCODER -#define LODEPNG_COMPILE_ENCODER -#endif - -/*the optional built in harddisk file loading and saving functions*/ -#ifndef LODEPNG_NO_COMPILE_DISK -#define LODEPNG_COMPILE_DISK -#endif - -/*support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks*/ -#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS -#define LODEPNG_COMPILE_ANCILLARY_CHUNKS -#endif - -/*ability to convert error numerical codes to English text string*/ -#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT -#define LODEPNG_COMPILE_ERROR_TEXT -#endif - -/*Compile the default allocators (C's free, malloc and realloc). If you disable this, -you can define the functions lodepng_free, lodepng_malloc and lodepng_realloc in your -source files with custom allocators.*/ -#ifndef LODEPNG_NO_COMPILE_ALLOCATORS -#define LODEPNG_COMPILE_ALLOCATORS -#endif - -/*compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)*/ -#ifdef __cplusplus -#ifndef LODEPNG_NO_COMPILE_CPP -#define LODEPNG_COMPILE_CPP -#endif -#endif - -#ifdef LODEPNG_COMPILE_CPP -#include -#include -#endif /*LODEPNG_COMPILE_CPP*/ - -#ifdef LODEPNG_COMPILE_PNG -/*The PNG color types (also used for raw image).*/ -typedef enum LodePNGColorType { - LCT_GREY = 0, /*grayscale: 1,2,4,8,16 bit*/ - LCT_RGB = 2, /*RGB: 8,16 bit*/ - LCT_PALETTE = 3, /*palette: 1,2,4,8 bit*/ - LCT_GREY_ALPHA = 4, /*grayscale with alpha: 8,16 bit*/ - LCT_RGBA = 6, /*RGB with alpha: 8,16 bit*/ - /*LCT_MAX_OCTET_VALUE lets the compiler allow this enum to represent any invalid - byte value from 0 to 255 that could be present in an invalid PNG file header. Do - not use, compare with or set the name LCT_MAX_OCTET_VALUE, instead either use - the valid color type names above, or numeric values like 1 or 7 when checking for - particular disallowed color type byte values, or cast to integer to print it.*/ - LCT_MAX_OCTET_VALUE = 255 -} LodePNGColorType; - -#ifdef LODEPNG_COMPILE_DECODER -/* -Converts PNG data in memory to raw pixel data. -out: Output parameter. Pointer to buffer that will contain the raw pixel data. - After decoding, its size is w * h * (bytes per pixel) bytes larger than - initially. Bytes per pixel depends on colortype and bitdepth. - Must be freed after usage with free(*out). - Note: for 16-bit per channel colors, uses big endian format like PNG does. -w: Output parameter. Pointer to width of pixel data. -h: Output parameter. Pointer to height of pixel data. -in: Memory buffer with the PNG file. -insize: size of the in buffer. -colortype: the desired color type for the raw output image. See explanation on PNG color types. -bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). -*/ -unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image*/ -unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize); - -/*Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image*/ -unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, - const unsigned char* in, size_t insize); - -#ifdef LODEPNG_COMPILE_DISK -/* -Load PNG from disk, from file with given name. -Same as the other decode functions, but instead takes a filename as input. -*/ -unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image.*/ -unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename); - -/*Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image.*/ -unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, - const char* filename); -#endif /*LODEPNG_COMPILE_DISK*/ -#endif /*LODEPNG_COMPILE_DECODER*/ - - -#ifdef LODEPNG_COMPILE_ENCODER -/* -Converts raw pixel data into a PNG image in memory. The colortype and bitdepth - of the output PNG image cannot be chosen, they are automatically determined - by the colortype, bitdepth and content of the input pixel data. - Note: for 16-bit per channel colors, needs big endian format like PNG does. -out: Output parameter. Pointer to buffer that will contain the PNG image data. - Must be freed after usage with free(*out). -outsize: Output parameter. Pointer to the size in bytes of the out buffer. -image: The raw pixel data to encode. The size of this buffer should be - w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth. -w: width of the raw pixel data in pixels. -h: height of the raw pixel data in pixels. -colortype: the color type of the raw input image. See explanation on PNG color types. -bitdepth: the bit depth of the raw input image. See explanation on PNG color types. -Return value: LodePNG error code (0 means no error). -*/ -unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image.*/ -unsigned lodepng_encode32(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h); - -/*Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image.*/ -unsigned lodepng_encode24(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h); - -#ifdef LODEPNG_COMPILE_DISK -/* -Converts raw pixel data into a PNG file on disk. -Same as the other encode functions, but instead takes a filename as output. -NOTE: This overwrites existing files without warning! -*/ -unsigned lodepng_encode_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h, - LodePNGColorType colortype, unsigned bitdepth); - -/*Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image.*/ -unsigned lodepng_encode32_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h); - -/*Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image.*/ -unsigned lodepng_encode24_file(const char* filename, - const unsigned char* image, unsigned w, unsigned h); -#endif /*LODEPNG_COMPILE_DISK*/ -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -#ifdef LODEPNG_COMPILE_CPP -namespace lodepng { -#ifdef LODEPNG_COMPILE_DECODER -/*Same as lodepng_decode_memory, but decodes to an std::vector. The colortype -is the format to output the pixels to. Default is RGBA 8-bit per channel.*/ -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const unsigned char* in, size_t insize, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::vector& in, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#ifdef LODEPNG_COMPILE_DISK -/* -Converts PNG file from disk to raw pixel data in memory. -Same as the other decode functions, but instead takes a filename as input. -*/ -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - const std::string& filename, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#endif /* LODEPNG_COMPILE_DISK */ -#endif /* LODEPNG_COMPILE_DECODER */ - -#ifdef LODEPNG_COMPILE_ENCODER -/*Same as lodepng_encode_memory, but encodes to an std::vector. colortype -is that of the raw input data. The output PNG color type will be auto chosen.*/ -unsigned encode(std::vector& out, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#ifdef LODEPNG_COMPILE_DISK -/* -Converts 32-bit RGBA raw pixel data into a PNG file on disk. -Same as the other encode functions, but instead takes a filename as output. -NOTE: This overwrites existing files without warning! -*/ -unsigned encode(const std::string& filename, - const unsigned char* in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -unsigned encode(const std::string& filename, - const std::vector& in, unsigned w, unsigned h, - LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); -#endif /* LODEPNG_COMPILE_DISK */ -#endif /* LODEPNG_COMPILE_ENCODER */ -} /* namespace lodepng */ -#endif /*LODEPNG_COMPILE_CPP*/ -#endif /*LODEPNG_COMPILE_PNG*/ - -#ifdef LODEPNG_COMPILE_ERROR_TEXT -/*Returns an English description of the numerical error code.*/ -const char* lodepng_error_text(unsigned code); -#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ - -#ifdef LODEPNG_COMPILE_DECODER -/*Settings for zlib decompression*/ -typedef struct LodePNGDecompressSettings LodePNGDecompressSettings; -struct LodePNGDecompressSettings { - /* Check LodePNGDecoderSettings for more ignorable errors such as ignore_crc */ - unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ - unsigned ignore_nlen; /*ignore complement of len checksum in uncompressed blocks*/ - - /*use custom zlib decoder instead of built in one (default: null)*/ - unsigned (*custom_zlib)(unsigned char**, size_t*, - const unsigned char*, size_t, - const LodePNGDecompressSettings*); - /*use custom deflate decoder instead of built in one (default: null) - if custom_zlib is not null, custom_inflate is ignored (the zlib format uses deflate)*/ - unsigned (*custom_inflate)(unsigned char**, size_t*, - const unsigned char*, size_t, - const LodePNGDecompressSettings*); - - const void* custom_context; /*optional custom settings for custom functions*/ -}; - -extern const LodePNGDecompressSettings lodepng_default_decompress_settings; -void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/* -Settings for zlib compression. Tweaking these settings tweaks the balance -between speed and compression ratio. -*/ -typedef struct LodePNGCompressSettings LodePNGCompressSettings; -struct LodePNGCompressSettings /*deflate = compress*/ { - /*LZ77 related settings*/ - unsigned btype; /*the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression.*/ - unsigned use_lz77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ - unsigned windowsize; /*must be a power of two <= 32768. higher compresses more but is slower. Default value: 2048.*/ - unsigned minmatch; /*minimum lz77 length. 3 is normally best, 6 can be better for some PNGs. Default: 0*/ - unsigned nicematch; /*stop searching if >= this length found. Set to 258 for best compression. Default: 128*/ - unsigned lazymatching; /*use lazy matching: better compression but a bit slower. Default: true*/ - - /*use custom zlib encoder instead of built in one (default: null)*/ - unsigned (*custom_zlib)(unsigned char**, size_t*, - const unsigned char*, size_t, - const LodePNGCompressSettings*); - /*use custom deflate encoder instead of built in one (default: null) - if custom_zlib is used, custom_deflate is ignored since only the built in - zlib function will call custom_deflate*/ - unsigned (*custom_deflate)(unsigned char**, size_t*, - const unsigned char*, size_t, - const LodePNGCompressSettings*); - - const void* custom_context; /*optional custom settings for custom functions*/ -}; - -extern const LodePNGCompressSettings lodepng_default_compress_settings; -void lodepng_compress_settings_init(LodePNGCompressSettings* settings); -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_PNG -/* -Color mode of an image. Contains all information required to decode the pixel -bits to RGBA colors. This information is the same as used in the PNG file -format, and is used both for PNG and raw image data in LodePNG. -*/ -typedef struct LodePNGColorMode { - /*header (IHDR)*/ - LodePNGColorType colortype; /*color type, see PNG standard or documentation further in this header file*/ - unsigned bitdepth; /*bits per sample, see PNG standard or documentation further in this header file*/ - - /* - palette (PLTE and tRNS) - - Dynamically allocated with the colors of the palette, including alpha. - When encoding a PNG, to store your colors in the palette of the LodePNGColorMode, first use - lodepng_palette_clear, then for each color use lodepng_palette_add. - If you encode an image without alpha with palette, don't forget to put value 255 in each A byte of the palette. - - When decoding, by default you can ignore this palette, since LodePNG already - fills the palette colors in the pixels of the raw RGBA output. - - The palette is only supported for color type 3. - */ - unsigned char* palette; /*palette in RGBARGBA... order. When allocated, must be either 0, or have size 1024*/ - size_t palettesize; /*palette size in number of colors (amount of bytes is 4 * palettesize)*/ - - /* - transparent color key (tRNS) - - This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit. - For grayscale PNGs, r, g and b will all 3 be set to the same. - - When decoding, by default you can ignore this information, since LodePNG sets - pixels with this key to transparent already in the raw RGBA output. - - The color key is only supported for color types 0 and 2. - */ - unsigned key_defined; /*is a transparent color key given? 0 = false, 1 = true*/ - unsigned key_r; /*red/grayscale component of color key*/ - unsigned key_g; /*green component of color key*/ - unsigned key_b; /*blue component of color key*/ -} LodePNGColorMode; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_color_mode_init(LodePNGColorMode* info); -void lodepng_color_mode_cleanup(LodePNGColorMode* info); -/*return value is error code (0 means no error)*/ -unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source); -/* Makes a temporary LodePNGColorMode that does not need cleanup (no palette) */ -LodePNGColorMode lodepng_color_mode_make(LodePNGColorType colortype, unsigned bitdepth); - -void lodepng_palette_clear(LodePNGColorMode* info); -/*add 1 color to the palette*/ -unsigned lodepng_palette_add(LodePNGColorMode* info, - unsigned char r, unsigned char g, unsigned char b, unsigned char a); - -/*get the total amount of bits per pixel, based on colortype and bitdepth in the struct*/ -unsigned lodepng_get_bpp(const LodePNGColorMode* info); -/*get the amount of color channels used, based on colortype in the struct. -If a palette is used, it counts as 1 channel.*/ -unsigned lodepng_get_channels(const LodePNGColorMode* info); -/*is it a grayscale type? (only colortype 0 or 4)*/ -unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info); -/*has it got an alpha channel? (only colortype 2 or 6)*/ -unsigned lodepng_is_alpha_type(const LodePNGColorMode* info); -/*has it got a palette? (only colortype 3)*/ -unsigned lodepng_is_palette_type(const LodePNGColorMode* info); -/*only returns true if there is a palette and there is a value in the palette with alpha < 255. -Loops through the palette to check this.*/ -unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info); -/* -Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image. -Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels). -Returns false if the image can only have opaque pixels. -In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values, -or if "key_defined" is true. -*/ -unsigned lodepng_can_have_alpha(const LodePNGColorMode* info); -/*Returns the byte size of a raw image buffer with given width, height and color mode*/ -size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -/*The information of a Time chunk in PNG.*/ -typedef struct LodePNGTime { - unsigned year; /*2 bytes used (0-65535)*/ - unsigned month; /*1-12*/ - unsigned day; /*1-31*/ - unsigned hour; /*0-23*/ - unsigned minute; /*0-59*/ - unsigned second; /*0-60 (to allow for leap seconds)*/ -} LodePNGTime; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -/*Information about the PNG image, except pixels, width and height.*/ -typedef struct LodePNGInfo { - /*header (IHDR), palette (PLTE) and transparency (tRNS) chunks*/ - unsigned compression_method;/*compression method of the original file. Always 0.*/ - unsigned filter_method; /*filter method of the original file*/ - unsigned interlace_method; /*interlace method of the original file: 0=none, 1=Adam7*/ - LodePNGColorMode color; /*color type and bits, palette and transparency of the PNG file*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /* - Suggested background color chunk (bKGD) - - This uses the same color mode and bit depth as the PNG (except no alpha channel), - with values truncated to the bit depth in the unsigned integer. - - For grayscale and palette PNGs, the value is stored in background_r. The values - in background_g and background_b are then unused. - - So when decoding, you may get these in a different color mode than the one you requested - for the raw pixels. - - When encoding with auto_convert, you must use the color model defined in info_png.color for - these values. The encoder normally ignores info_png.color when auto_convert is on, but will - use it to interpret these values (and convert copies of them to its chosen color model). - - When encoding, avoid setting this to an expensive color, such as a non-gray value - when the image is gray, or the compression will be worse since it will be forced to - write the PNG with a more expensive color mode (when auto_convert is on). - - The decoder does not use this background color to edit the color of pixels. This is a - completely optional metadata feature. - */ - unsigned background_defined; /*is a suggested background color given?*/ - unsigned background_r; /*red/gray/palette component of suggested background color*/ - unsigned background_g; /*green component of suggested background color*/ - unsigned background_b; /*blue component of suggested background color*/ - - /* - non-international text chunks (tEXt and zTXt) - - The char** arrays each contain num strings. The actual messages are in - text_strings, while text_keys are keywords that give a short description what - the actual text represents, e.g. Title, Author, Description, or anything else. - - All the string fields below including keys, names and language tags are null terminated. - The PNG specification uses null characters for the keys, names and tags, and forbids null - characters to appear in the main text which is why we can use null termination everywhere here. - - A keyword is minimum 1 character and maximum 79 characters long. It's - discouraged to use a single line length longer than 79 characters for texts. - - Don't allocate these text buffers yourself. Use the init/cleanup functions - correctly and use lodepng_add_text and lodepng_clear_text. - */ - size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ - char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ - char** text_strings; /*the actual text*/ - - /* - international text chunks (iTXt) - Similar to the non-international text chunks, but with additional strings - "langtags" and "transkeys". - */ - size_t itext_num; /*the amount of international texts in this PNG*/ - char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ - char** itext_langtags; /*language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ - char** itext_transkeys; /*keyword translated to the international language - UTF-8 string*/ - char** itext_strings; /*the actual international text - UTF-8 string*/ - - /*time chunk (tIME)*/ - unsigned time_defined; /*set to 1 to make the encoder generate a tIME chunk*/ - LodePNGTime time; - - /*phys chunk (pHYs)*/ - unsigned phys_defined; /*if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one*/ - unsigned phys_x; /*pixels per unit in x direction*/ - unsigned phys_y; /*pixels per unit in y direction*/ - unsigned phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ - - /* - Color profile related chunks: gAMA, cHRM, sRGB, iCPP - - LodePNG does not apply any color conversions on pixels in the encoder or decoder and does not interpret these color - profile values. It merely passes on the information. If you wish to use color profiles and convert colors, please - use these values with a color management library. - - See the PNG, ICC and sRGB specifications for more information about the meaning of these values. - */ - - /* gAMA chunk: optional, overridden by sRGB or iCCP if those are present. */ - unsigned gama_defined; /* Whether a gAMA chunk is present (0 = not present, 1 = present). */ - unsigned gama_gamma; /* Gamma exponent times 100000 */ - - /* cHRM chunk: optional, overridden by sRGB or iCCP if those are present. */ - unsigned chrm_defined; /* Whether a cHRM chunk is present (0 = not present, 1 = present). */ - unsigned chrm_white_x; /* White Point x times 100000 */ - unsigned chrm_white_y; /* White Point y times 100000 */ - unsigned chrm_red_x; /* Red x times 100000 */ - unsigned chrm_red_y; /* Red y times 100000 */ - unsigned chrm_green_x; /* Green x times 100000 */ - unsigned chrm_green_y; /* Green y times 100000 */ - unsigned chrm_blue_x; /* Blue x times 100000 */ - unsigned chrm_blue_y; /* Blue y times 100000 */ - - /* - sRGB chunk: optional. May not appear at the same time as iCCP. - If gAMA is also present gAMA must contain value 45455. - If cHRM is also present cHRM must contain respectively 31270,32900,64000,33000,30000,60000,15000,6000. - */ - unsigned srgb_defined; /* Whether an sRGB chunk is present (0 = not present, 1 = present). */ - unsigned srgb_intent; /* Rendering intent: 0=perceptual, 1=rel. colorimetric, 2=saturation, 3=abs. colorimetric */ - - /* - iCCP chunk: optional. May not appear at the same time as sRGB. - - LodePNG does not parse or use the ICC profile (except its color space header field for an edge case), a - separate library to handle the ICC data (not included in LodePNG) format is needed to use it for color - management and conversions. - - For encoding, if iCCP is present, gAMA and cHRM are recommended to be added as well with values that match the ICC - profile as closely as possible, if you wish to do this you should provide the correct values for gAMA and cHRM and - enable their '_defined' flags since LodePNG will not automatically compute them from the ICC profile. - - For encoding, the ICC profile is required by the PNG specification to be an "RGB" profile for non-gray - PNG color types and a "GRAY" profile for gray PNG color types. If you disable auto_convert, you must ensure - the ICC profile type matches your requested color type, else the encoder gives an error. If auto_convert is - enabled (the default), and the ICC profile is not a good match for the pixel data, this will result in an encoder - error if the pixel data has non-gray pixels for a GRAY profile, or a silent less-optimal compression of the pixel - data if the pixels could be encoded as grayscale but the ICC profile is RGB. - - To avoid this do not set an ICC profile in the image unless there is a good reason for it, and when doing so - make sure you compute it carefully to avoid the above problems. - */ - unsigned iccp_defined; /* Whether an iCCP chunk is present (0 = not present, 1 = present). */ - char* iccp_name; /* Null terminated string with profile name, 1-79 bytes */ - /* - The ICC profile in iccp_profile_size bytes. - Don't allocate this buffer yourself. Use the init/cleanup functions - correctly and use lodepng_set_icc and lodepng_clear_icc. - */ - unsigned char* iccp_profile; - unsigned iccp_profile_size; /* The size of iccp_profile in bytes */ - - /* End of color profile related chunks */ - - - /* - unknown chunks: chunks not known by LodePNG, passed on byte for byte. - - There are 3 buffers, one for each position in the PNG where unknown chunks can appear. - Each buffer contains all unknown chunks for that position consecutively. - The 3 positions are: - 0: between IHDR and PLTE, 1: between PLTE and IDAT, 2: between IDAT and IEND. - - For encoding, do not store critical chunks or known chunks that are enabled with a "_defined" flag - above in here, since the encoder will blindly follow this and could then encode an invalid PNG file - (such as one with two IHDR chunks or the disallowed combination of sRGB with iCCP). But do use - this if you wish to store an ancillary chunk that is not supported by LodePNG (such as sPLT or hIST), - or any non-standard PNG chunk. - - Do not allocate or traverse this data yourself. Use the chunk traversing functions declared - later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct. - */ - unsigned char* unknown_chunks_data[3]; - size_t unknown_chunks_size[3]; /*size in bytes of the unknown chunks, given for protection*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGInfo; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_info_init(LodePNGInfo* info); -void lodepng_info_cleanup(LodePNGInfo* info); -/*return value is error code (0 means no error)*/ -unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source); - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS -unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /*push back both texts at once*/ -void lodepng_clear_text(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ - -unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, - const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ -void lodepng_clear_itext(LodePNGInfo* info); /*use this to clear the itexts again after you filled them in*/ - -/*replaces if exists*/ -unsigned lodepng_set_icc(LodePNGInfo* info, const char* name, const unsigned char* profile, unsigned profile_size); -void lodepng_clear_icc(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ - -/* -Converts raw buffer from one color type to another color type, based on -LodePNGColorMode structs to describe the input and output color type. -See the reference manual at the end of this header file to see which color conversions are supported. -return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported) -The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel -of the output color type (lodepng_get_bpp). -For < 8 bpp images, there should not be padding bits at the end of scanlines. -For 16-bit per channel colors, uses big endian format like PNG does. -Return value is LodePNG error code -*/ -unsigned lodepng_convert(unsigned char* out, const unsigned char* in, - const LodePNGColorMode* mode_out, const LodePNGColorMode* mode_in, - unsigned w, unsigned h); - -#ifdef LODEPNG_COMPILE_DECODER -/* -Settings for the decoder. This contains settings for the PNG and the Zlib -decoder, but not the Info settings from the Info structs. -*/ -typedef struct LodePNGDecoderSettings { - LodePNGDecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ - - /* Check LodePNGDecompressSettings for more ignorable errors such as ignore_adler32 */ - unsigned ignore_crc; /*ignore CRC checksums*/ - unsigned ignore_critical; /*ignore unknown critical chunks*/ - unsigned ignore_end; /*ignore issues at end of file if possible (missing IEND chunk, too large chunk, ...)*/ - /* TODO: make a system involving warnings with levels and a strict mode instead. Other potentially recoverable - errors: srgb rendering intent value, size of content of ancillary chunks, more than 79 characters for some - strings, placement/combination rules for ancillary chunks, crc of unknown chunks, allowed characters - in string keys, etc... */ - - unsigned color_convert; /*whether to convert the PNG to the color type you want. Default: yes*/ - -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ - /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ - unsigned remember_unknown_chunks; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGDecoderSettings; - -void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/*automatically use color type with less bits per pixel if losslessly possible. Default: AUTO*/ -typedef enum LodePNGFilterStrategy { - /*every filter at zero*/ - LFS_ZERO = 0, - /*every filter at 1, 2, 3 or 4 (paeth), unlike LFS_ZERO not a good choice, but for testing*/ - LFS_ONE = 1, - LFS_TWO = 2, - LFS_THREE = 3, - LFS_FOUR = 4, - /*Use filter that gives minimum sum, as described in the official PNG filter heuristic.*/ - LFS_MINSUM, - /*Use the filter type that gives smallest Shannon entropy for this scanline. Depending - on the image, this is better or worse than minsum.*/ - LFS_ENTROPY, - /* - Brute-force-search PNG filters by compressing each filter for each scanline. - Experimental, very slow, and only rarely gives better compression than MINSUM. - */ - LFS_BRUTE_FORCE, - /*use predefined_filters buffer: you specify the filter type for each scanline*/ - LFS_PREDEFINED -} LodePNGFilterStrategy; - -/*Gives characteristics about the integer RGBA colors of the image (count, alpha channel usage, bit depth, ...), -which helps decide which color model to use for encoding. -Used internally by default if "auto_convert" is enabled. Public because it's useful for custom algorithms.*/ -typedef struct LodePNGColorStats { - unsigned colored; /*not grayscale*/ - unsigned key; /*image is not opaque and color key is possible instead of full alpha*/ - unsigned short key_r; /*key values, always as 16-bit, in 8-bit case the byte is duplicated, e.g. 65535 means 255*/ - unsigned short key_g; - unsigned short key_b; - unsigned alpha; /*image is not opaque and alpha channel or alpha palette required*/ - unsigned numcolors; /*amount of colors, up to 257. Not valid if bits == 16 or allow_palette is disabled.*/ - unsigned char palette[1024]; /*Remembers up to the first 256 RGBA colors, in no particular order, only valid when numcolors is valid*/ - unsigned bits; /*bits per channel (not for palette). 1,2 or 4 for grayscale only. 16 if 16-bit per channel required.*/ - size_t numpixels; - - /*user settings for computing/using the stats*/ - unsigned allow_palette; /*default 1. if 0, disallow choosing palette colortype in auto_choose_color, and don't count numcolors*/ - unsigned allow_greyscale; /*default 1. if 0, choose RGB or RGBA even if the image only has gray colors*/ -} LodePNGColorStats; - -void lodepng_color_stats_init(LodePNGColorStats* stats); - -/*Get a LodePNGColorStats of the image. The stats must already have been inited.*/ -void lodepng_compute_color_stats(LodePNGColorStats* stats, - const unsigned char* image, unsigned w, unsigned h, - const LodePNGColorMode* mode_in); -/*Computes a minimal PNG color model that can contain all colors as indicated by the stats and it settings. -The stats should be computed with lodepng_compute_color_stats. -mode_in is raw color profile of the image the stats were computed on, to copy palette order from when relevant. -Minimal PNG color model means the color type and bit depth that gives smallest amount of bits in the output image, -e.g. gray if only grayscale pixels, palette if less than 256 colors, color key if only single transparent color, ... -LodePNG uses this function internally if auto_convert is enabled (it is by default). -*/ -unsigned lodepng_auto_choose_color(LodePNGColorMode* mode_out, - const LodePNGColorMode* mode_in, - const LodePNGColorMode* stats); - -/*Settings for the encoder.*/ -typedef struct LodePNGEncoderSettings { - LodePNGCompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ - - unsigned auto_convert; /*automatically choose output PNG color type. Default: true*/ - - /*If true, follows the official PNG heuristic: if the PNG uses a palette or lower than - 8 bit depth, set all filters to zero. Otherwise use the filter_strategy. Note that to - completely follow the official PNG heuristic, filter_palette_zero must be true and - filter_strategy must be LFS_MINSUM*/ - unsigned filter_palette_zero; - /*Which filter strategy to use when not using zeroes due to filter_palette_zero. - Set filter_palette_zero to 0 to ensure always using your chosen strategy. Default: LFS_MINSUM*/ - LodePNGFilterStrategy filter_strategy; - /*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with - the same length as the amount of scanlines in the image, and each value must <= 5. You - have to cleanup this buffer, LodePNG will never free it. Don't forget that filter_palette_zero - must be set to 0 to ensure this is also used on palette or low bitdepth images.*/ - const unsigned char* predefined_filters; - - /*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette). - If colortype is 3, PLTE is _always_ created.*/ - unsigned force_palette; -#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS - /*add LodePNG identifier and version as a text chunk, for debugging*/ - unsigned add_id; - /*encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks*/ - unsigned text_compression; -#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ -} LodePNGEncoderSettings; - -void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings); -#endif /*LODEPNG_COMPILE_ENCODER*/ - - -#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) -/*The settings, state and information for extended encoding and decoding.*/ -typedef struct LodePNGState { -#ifdef LODEPNG_COMPILE_DECODER - LodePNGDecoderSettings decoder; /*the decoding settings*/ -#endif /*LODEPNG_COMPILE_DECODER*/ -#ifdef LODEPNG_COMPILE_ENCODER - LodePNGEncoderSettings encoder; /*the encoding settings*/ -#endif /*LODEPNG_COMPILE_ENCODER*/ - LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ - LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ - unsigned error; -#ifdef LODEPNG_COMPILE_CPP - /* For the lodepng::State subclass. */ - virtual ~LodePNGState(){} -#endif -} LodePNGState; - -/*init, cleanup and copy functions to use with this struct*/ -void lodepng_state_init(LodePNGState* state); -void lodepng_state_cleanup(LodePNGState* state); -void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source); -#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ - -#ifdef LODEPNG_COMPILE_DECODER -/* -Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and -getting much more information about the PNG image and color mode. -*/ -unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize); - -/* -Read the PNG header, but not the actual data. This returns only the information -that is in the IHDR chunk of the PNG, such as width, height and color type. The -information is placed in the info_png field of the LodePNGState. -*/ -unsigned lodepng_inspect(unsigned* w, unsigned* h, - LodePNGState* state, - const unsigned char* in, size_t insize); -#endif /*LODEPNG_COMPILE_DECODER*/ - -/* -Reads one metadata chunk (other than IHDR) of the PNG file and outputs what it -read in the state. Returns error code on failure. -Use lodepng_inspect first with a new state, then e.g. lodepng_chunk_find_const -to find the desired chunk type, and if non null use lodepng_inspect_chunk (with -chunk_pointer - start_of_file as pos). -Supports most metadata chunks from the PNG standard (gAMA, bKGD, tEXt, ...). -Ignores unsupported, unknown, non-metadata or IHDR chunks (without error). -Requirements: &in[pos] must point to start of a chunk, must use regular -lodepng_inspect first since format of most other chunks depends on IHDR, and if -there is a PLTE chunk, that one must be inspected before tRNS or bKGD. -*/ -unsigned lodepng_inspect_chunk(LodePNGState* state, size_t pos, - const unsigned char* in, size_t insize); - -#ifdef LODEPNG_COMPILE_ENCODER -/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ -unsigned lodepng_encode(unsigned char** out, size_t* outsize, - const unsigned char* image, unsigned w, unsigned h, - LodePNGState* state); -#endif /*LODEPNG_COMPILE_ENCODER*/ - -/* -The lodepng_chunk functions are normally not needed, except to traverse the -unknown chunks stored in the LodePNGInfo struct, or add new ones to it. -It also allows traversing the chunks of an encoded PNG file yourself. - -The chunk pointer always points to the beginning of the chunk itself, that is -the first byte of the 4 length bytes. - -In the PNG file format, chunks have the following format: --4 bytes length: length of the data of the chunk in bytes (chunk itself is 12 bytes longer) --4 bytes chunk type (ASCII a-z,A-Z only, see below) --length bytes of data (may be 0 bytes if length was 0) --4 bytes of CRC, computed on chunk name + data - -The first chunk starts at the 8th byte of the PNG file, the entire rest of the file -exists out of concatenated chunks with the above format. - -PNG standard chunk ASCII naming conventions: --First byte: uppercase = critical, lowercase = ancillary --Second byte: uppercase = public, lowercase = private --Third byte: must be uppercase --Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy -*/ - -/* -Gets the length of the data of the chunk. Total chunk length has 12 bytes more. -There must be at least 4 bytes to read from. If the result value is too large, -it may be corrupt data. -*/ -unsigned lodepng_chunk_length(const unsigned char* chunk); - -/*puts the 4-byte type in null terminated string*/ -void lodepng_chunk_type(char type[5], const unsigned char* chunk); - -/*check if the type is the given type*/ -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type); - -/*0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)*/ -unsigned char lodepng_chunk_ancillary(const unsigned char* chunk); - -/*0: public, 1: private (see PNG standard)*/ -unsigned char lodepng_chunk_private(const unsigned char* chunk); - -/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)*/ -unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk); - -/*get pointer to the data of the chunk, where the input points to the header of the chunk*/ -unsigned char* lodepng_chunk_data(unsigned char* chunk); -const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk); - -/*returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)*/ -unsigned lodepng_chunk_check_crc(const unsigned char* chunk); - -/*generates the correct CRC from the data and puts it in the last 4 bytes of the chunk*/ -void lodepng_chunk_generate_crc(unsigned char* chunk); - -/* -Iterate to next chunks, allows iterating through all chunks of the PNG file. -Input must be at the beginning of a chunk (result of a previous lodepng_chunk_next call, -or the 8th byte of a PNG file which always has the first chunk), or alternatively may -point to the first byte of the PNG file (which is not a chunk but the magic header, the -function will then skip over it and return the first real chunk). -Expects at least 8 readable bytes of memory in the input pointer. -Will output pointer to the start of the next chunk or the end of the file if there -is no more chunk after this. Start this process at the 8th byte of the PNG file. -In a non-corrupt PNG file, the last chunk should have name "IEND". -*/ -unsigned char* lodepng_chunk_next(unsigned char* chunk); -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk); - -/*Finds the first chunk with the given type in the range [chunk, end), or returns NULL if not found.*/ -unsigned char* lodepng_chunk_find(unsigned char* chunk, const unsigned char* end, const char type[5]); -const unsigned char* lodepng_chunk_find_const(const unsigned char* chunk, const unsigned char* end, const char type[5]); - -/* -Appends chunk to the data in out. The given chunk should already have its chunk header. -The out variable and outlength are updated to reflect the new reallocated buffer. -Returns error code (0 if it went ok) -*/ -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk); - -/* -Appends new chunk to out. The chunk to append is given by giving its length, type -and data separately. The type is a 4-letter string. -The out variable and outlength are updated to reflect the new reallocated buffer. -Returne error code (0 if it went ok) -*/ -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data); - - -/*Calculate CRC32 of buffer*/ -unsigned lodepng_crc32(const unsigned char* buf, size_t len); -#endif /*LODEPNG_COMPILE_PNG*/ - - -#ifdef LODEPNG_COMPILE_ZLIB -/* -This zlib part can be used independently to zlib compress and decompress a -buffer. It cannot be used to create gzip files however, and it only supports the -part of zlib that is required for PNG, it does not support dictionaries. -*/ - -#ifdef LODEPNG_COMPILE_DECODER -/*Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use.*/ -unsigned lodepng_inflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); - -/* -Decompresses Zlib data. Reallocates the out buffer and appends the data. The -data must be according to the zlib specification. -Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage. -*/ -unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGDecompressSettings* settings); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/* -Compresses data with Zlib. Reallocates the out buffer and appends the data. -Zlib adds a small header and trailer around the deflate data. -The data is output in the format of the zlib specification. -Either, *out must be NULL and *outsize must be 0, or, *out must be a valid -buffer and *outsize its size in bytes. out must be freed by user after usage. -*/ -unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); - -/* -Find length-limited Huffman code for given frequencies. This function is in the -public interface only for tests, it's used internally by lodepng_deflate. -*/ -unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, - size_t numcodes, unsigned maxbitlen); - -/*Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use.*/ -unsigned lodepng_deflate(unsigned char** out, size_t* outsize, - const unsigned char* in, size_t insize, - const LodePNGCompressSettings* settings); - -#endif /*LODEPNG_COMPILE_ENCODER*/ -#endif /*LODEPNG_COMPILE_ZLIB*/ - -#ifdef LODEPNG_COMPILE_DISK -/* -Load a file from disk into buffer. The function allocates the out buffer, and -after usage you should free it. -out: output parameter, contains pointer to loaded buffer. -outsize: output parameter, size of the allocated out buffer -filename: the path to the file to load -return value: error code (0 means ok) -*/ -unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename); - -/* -Save a file from buffer to disk. Warning, if it exists, this function overwrites -the file without warning! -buffer: the buffer to write -buffersize: size of the buffer to write -filename: the path to the file to save to -return value: error code (0 means ok) -*/ -unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename); -#endif /*LODEPNG_COMPILE_DISK*/ - -#ifdef LODEPNG_COMPILE_CPP -/* The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers. */ -namespace lodepng { -#ifdef LODEPNG_COMPILE_PNG -class State : public LodePNGState { - public: - State(); - State(const State& other); - virtual ~State(); - State& operator=(const State& other); -}; - -#ifdef LODEPNG_COMPILE_DECODER -/* Same as other lodepng::decode, but using a State for more settings and information. */ -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const unsigned char* in, size_t insize); -unsigned decode(std::vector& out, unsigned& w, unsigned& h, - State& state, - const std::vector& in); -#endif /*LODEPNG_COMPILE_DECODER*/ - -#ifdef LODEPNG_COMPILE_ENCODER -/* Same as other lodepng::encode, but using a State for more settings and information. */ -unsigned encode(std::vector& out, - const unsigned char* in, unsigned w, unsigned h, - State& state); -unsigned encode(std::vector& out, - const std::vector& in, unsigned w, unsigned h, - State& state); -#endif /*LODEPNG_COMPILE_ENCODER*/ - -#ifdef LODEPNG_COMPILE_DISK -/* -Load a file from disk into an std::vector. -return value: error code (0 means ok) -*/ -unsigned load_file(std::vector& buffer, const std::string& filename); - -/* -Save the binary data in an std::vector to a file on disk. The file is overwritten -without warning. -*/ -unsigned save_file(const std::vector& buffer, const std::string& filename); -#endif /* LODEPNG_COMPILE_DISK */ -#endif /* LODEPNG_COMPILE_PNG */ - -#ifdef LODEPNG_COMPILE_ZLIB -#ifdef LODEPNG_COMPILE_DECODER -/* Zlib-decompress an unsigned char buffer */ -unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); - -/* Zlib-decompress an std::vector */ -unsigned decompress(std::vector& out, const std::vector& in, - const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); -#endif /* LODEPNG_COMPILE_DECODER */ - -#ifdef LODEPNG_COMPILE_ENCODER -/* Zlib-compress an unsigned char buffer */ -unsigned compress(std::vector& out, const unsigned char* in, size_t insize, - const LodePNGCompressSettings& settings = lodepng_default_compress_settings); - -/* Zlib-compress an std::vector */ -unsigned compress(std::vector& out, const std::vector& in, - const LodePNGCompressSettings& settings = lodepng_default_compress_settings); -#endif /* LODEPNG_COMPILE_ENCODER */ -#endif /* LODEPNG_COMPILE_ZLIB */ -} /* namespace lodepng */ -#endif /*LODEPNG_COMPILE_CPP*/ - -/* -TODO: -[.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often -[.] check compatibility with various compilers - done but needs to be redone for every newer version -[X] converting color to 16-bit per channel types -[X] support color profile chunk types (but never let them touch RGB values by default) -[ ] support all public PNG chunk types (almost done except sBIT, sPLT and hIST) -[ ] make sure encoder generates no chunks with size > (2^31)-1 -[ ] partial decoding (stream processing) -[X] let the "isFullyOpaque" function check color keys and transparent palettes too -[X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl" -[ ] allow treating some errors like warnings, when image is recoverable (e.g. 69, 57, 58) -[ ] make warnings like: oob palette, checksum fail, data after iend, wrong/unknown crit chunk, no null terminator in text, ... -[ ] error messages with line numbers (and version) -[ ] errors in state instead of as return code? -[ ] new errors/warnings like suspiciously big decompressed ztxt or iccp chunk -[ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes -[ ] allow user to provide custom color conversion functions, e.g. for premultiplied alpha, padding bits or not, ... -[ ] allow user to give data (void*) to custom allocator -[ ] provide alternatives for C library functions not present on some platforms (memcpy, ...) -[ ] rename "grey" to "gray" everywhere since "color" also uses US spelling (keep "grey" copies for backwards compatibility) -*/ - -#endif /*LODEPNG_H inclusion guard*/ - -/* -LodePNG Documentation ---------------------- - -0. table of contents --------------------- - - 1. about - 1.1. supported features - 1.2. features not supported - 2. C and C++ version - 3. security - 4. decoding - 5. encoding - 6. color conversions - 6.1. PNG color types - 6.2. color conversions - 6.3. padding bits - 6.4. A note about 16-bits per channel and endianness - 7. error values - 8. chunks and PNG editing - 9. compiler support - 10. examples - 10.1. decoder C++ example - 10.2. decoder C example - 11. state settings reference - 12. changes - 13. contact information - - -1. about --------- - -PNG is a file format to store raster images losslessly with good compression, -supporting different color types and alpha channel. - -LodePNG is a PNG codec according to the Portable Network Graphics (PNG) -Specification (Second Edition) - W3C Recommendation 10 November 2003. - -The specifications used are: - -*) Portable Network Graphics (PNG) Specification (Second Edition): - http://www.w3.org/TR/2003/REC-PNG-20031110 -*) RFC 1950 ZLIB Compressed Data Format version 3.3: - http://www.gzip.org/zlib/rfc-zlib.html -*) RFC 1951 DEFLATE Compressed Data Format Specification ver 1.3: - http://www.gzip.org/zlib/rfc-deflate.html - -The most recent version of LodePNG can currently be found at -http://lodev.org/lodepng/ - -LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds -extra functionality. - -LodePNG exists out of two files: --lodepng.h: the header file for both C and C++ --lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage - -If you want to start using LodePNG right away without reading this doc, get the -examples from the LodePNG website to see how to use it in code, or check the -smaller examples in chapter 13 here. - -LodePNG is simple but only supports the basic requirements. To achieve -simplicity, the following design choices were made: There are no dependencies -on any external library. There are functions to decode and encode a PNG with -a single function call, and extended versions of these functions taking a -LodePNGState struct allowing to specify or get more information. By default -the colors of the raw image are always RGB or RGBA, no matter what color type -the PNG file uses. To read and write files, there are simple functions to -convert the files to/from buffers in memory. - -This all makes LodePNG suitable for loading textures in games, demos and small -programs, ... It's less suitable for full fledged image editors, loading PNGs -over network (it requires all the image data to be available before decoding can -begin), life-critical systems, ... - -1.1. supported features ------------------------ - -The following features are supported by the decoder: - -*) decoding of PNGs with any color type, bit depth and interlace mode, to a 24- or 32-bit color raw image, - or the same color type as the PNG -*) encoding of PNGs, from any raw image to 24- or 32-bit color, or the same color type as the raw image -*) Adam7 interlace and deinterlace for any color type -*) loading the image from harddisk or decoding it from a buffer from other sources than harddisk -*) support for alpha channels, including RGBA color model, translucent palettes and color keying -*) zlib decompression (inflate) -*) zlib compression (deflate) -*) CRC32 and ADLER32 checksums -*) colorimetric color profile conversions: currently experimentally available in lodepng_util.cpp only, - plus alternatively ability to pass on chroma/gamma/ICC profile information to other color management system. -*) handling of unknown chunks, allowing making a PNG editor that stores custom and unknown chunks. -*) the following chunks are supported by both encoder and decoder: - IHDR: header information - PLTE: color palette - IDAT: pixel data - IEND: the final chunk - tRNS: transparency for palettized images - tEXt: textual information - zTXt: compressed textual information - iTXt: international textual information - bKGD: suggested background color - pHYs: physical dimensions - tIME: modification time - cHRM: RGB chromaticities - gAMA: RGB gamma correction - iCCP: ICC color profile - sRGB: rendering intent - -1.2. features not supported ---------------------------- - -The following features are _not_ supported: - -*) some features needed to make a conformant PNG-Editor might be still missing. -*) partial loading/stream processing. All data must be available and is processed in one call. -*) The following public chunks are not (yet) supported but treated as unknown chunks by LodePNG: - sBIT - hIST - sPLT - - -2. C and C++ version --------------------- - -The C version uses buffers allocated with alloc that you need to free() -yourself. You need to use init and cleanup functions for each struct whenever -using a struct from the C version to avoid exploits and memory leaks. - -The C++ version has extra functions with std::vectors in the interface and the -lodepng::State class which is a LodePNGState with constructor and destructor. - -These files work without modification for both C and C++ compilers because all -the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers -ignore it, and the C code is made to compile both with strict ISO C90 and C++. - -To use the C++ version, you need to rename the source file to lodepng.cpp -(instead of lodepng.c), and compile it with a C++ compiler. - -To use the C version, you need to rename the source file to lodepng.c (instead -of lodepng.cpp), and compile it with a C compiler. - - -3. Security ------------ - -Even if carefully designed, it's always possible that LodePNG contains possible -exploits. If you discover one, please let me know, and it will be fixed. - -When using LodePNG, care has to be taken with the C version of LodePNG, as well -as the C-style structs when working with C++. The following conventions are used -for all C-style structs: - --if a struct has a corresponding init function, always call the init function when making a new one --if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks --if a struct has a corresponding copy function, use the copy function instead of "=". - The destination must also be inited already. - - -4. Decoding ------------ - -Decoding converts a PNG compressed image to a raw pixel buffer. - -Most documentation on using the decoder is at its declarations in the header -above. For C, simple decoding can be done with functions such as -lodepng_decode32, and more advanced decoding can be done with the struct -LodePNGState and lodepng_decode. For C++, all decoding can be done with the -various lodepng::decode functions, and lodepng::State can be used for advanced -features. - -When using the LodePNGState, it uses the following fields for decoding: -*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here -*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get -*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use - -LodePNGInfo info_png --------------------- - -After decoding, this contains extra information of the PNG image, except the actual -pixels, width and height because these are already gotten directly from the decoder -functions. - -It contains for example the original color type of the PNG image, text comments, -suggested background color, etc... More details about the LodePNGInfo struct are -at its declaration documentation. - -LodePNGColorMode info_raw -------------------------- - -When decoding, here you can specify which color type you want -the resulting raw image to be. If this is different from the colortype of the -PNG, then the decoder will automatically convert the result. This conversion -always works, except if you want it to convert a color PNG to grayscale or to -a palette with missing colors. - -By default, 32-bit color is used for the result. - -LodePNGDecoderSettings decoder ------------------------------- - -The settings can be used to ignore the errors created by invalid CRC and Adler32 -chunks, and to disable the decoding of tEXt chunks. - -There's also a setting color_convert, true by default. If false, no conversion -is done, the resulting data will be as it was in the PNG (after decompression) -and you'll have to puzzle the colors of the pixels together yourself using the -color type information in the LodePNGInfo. - - -5. Encoding ------------ - -Encoding converts a raw pixel buffer to a PNG compressed image. - -Most documentation on using the encoder is at its declarations in the header -above. For C, simple encoding can be done with functions such as -lodepng_encode32, and more advanced decoding can be done with the struct -LodePNGState and lodepng_encode. For C++, all encoding can be done with the -various lodepng::encode functions, and lodepng::State can be used for advanced -features. - -Like the decoder, the encoder can also give errors. However it gives less errors -since the encoder input is trusted, the decoder input (a PNG image that could -be forged by anyone) is not trusted. - -When using the LodePNGState, it uses the following fields for encoding: -*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be. -*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has -*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use - -LodePNGInfo info_png --------------------- - -When encoding, you use this the opposite way as when decoding: for encoding, -you fill in the values you want the PNG to have before encoding. By default it's -not needed to specify a color type for the PNG since it's automatically chosen, -but it's possible to choose it yourself given the right settings. - -The encoder will not always exactly match the LodePNGInfo struct you give, -it tries as close as possible. Some things are ignored by the encoder. The -encoder uses, for example, the following settings from it when applicable: -colortype and bitdepth, text chunks, time chunk, the color key, the palette, the -background color, the interlace method, unknown chunks, ... - -When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk. -If the palette contains any colors for which the alpha channel is not 255 (so -there are translucent colors in the palette), it'll add a tRNS chunk. - -LodePNGColorMode info_raw -------------------------- - -You specify the color type of the raw image that you give to the input here, -including a possible transparent color key and palette you happen to be using in -your raw image data. - -By default, 32-bit color is assumed, meaning your input has to be in RGBA -format with 4 bytes (unsigned chars) per pixel. - -LodePNGEncoderSettings encoder ------------------------------- - -The following settings are supported (some are in sub-structs): -*) auto_convert: when this option is enabled, the encoder will -automatically choose the smallest possible color mode (including color key) that -can encode the colors of all pixels without information loss. -*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree, - 2 = dynamic huffman tree (best compression). Should be 2 for proper - compression. -*) use_lz77: whether or not to use LZ77 for compressed block types. Should be - true for proper compression. -*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value - 2048 by default, but can be set to 32768 for better, but slow, compression. -*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE - chunk if force_palette is true. This can used as suggested palette to convert - to by viewers that don't support more than 256 colors (if those still exist) -*) add_id: add text chunk "Encoder: LodePNG " to the image. -*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks. - zTXt chunks use zlib compression on the text. This gives a smaller result on - large texts but a larger result on small texts (such as a single program name). - It's all tEXt or all zTXt though, there's no separate setting per text yet. - - -6. color conversions --------------------- - -An important thing to note about LodePNG, is that the color type of the PNG, and -the color type of the raw image, are completely independent. By default, when -you decode a PNG, you get the result as a raw image in the color type you want, -no matter whether the PNG was encoded with a palette, grayscale or RGBA color. -And if you encode an image, by default LodePNG will automatically choose the PNG -color type that gives good compression based on the values of colors and amount -of colors in the image. It can be configured to let you control it instead as -well, though. - -To be able to do this, LodePNG does conversions from one color mode to another. -It can convert from almost any color type to any other color type, except the -following conversions: RGB to grayscale is not supported, and converting to a -palette when the palette doesn't have a required color is not supported. This is -not supported on purpose: this is information loss which requires a color -reduction algorithm that is beyond the scope of a PNG encoder (yes, RGB to gray -is easy, but there are multiple ways if you want to give some channels more -weight). - -By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB -color, no matter what color type the PNG has. And by default when encoding, -LodePNG automatically picks the best color model for the output PNG, and expects -the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control -the color format of the images yourself, you can skip this chapter. - -6.1. PNG color types --------------------- - -A PNG image can have many color types, ranging from 1-bit color to 64-bit color, -as well as palettized color modes. After the zlib decompression and unfiltering -in the PNG image is done, the raw pixel data will have that color type and thus -a certain amount of bits per pixel. If you want the output raw image after -decoding to have another color type, a conversion is done by LodePNG. - -The PNG specification gives the following color types: - -0: grayscale, bit depths 1, 2, 4, 8, 16 -2: RGB, bit depths 8 and 16 -3: palette, bit depths 1, 2, 4 and 8 -4: grayscale with alpha, bit depths 8 and 16 -6: RGBA, bit depths 8 and 16 - -Bit depth is the amount of bits per pixel per color channel. So the total amount -of bits per pixel is: amount of channels * bitdepth. - -6.2. color conversions ----------------------- - -As explained in the sections about the encoder and decoder, you can specify -color types and bit depths in info_png and info_raw to change the default -behaviour. - -If, when decoding, you want the raw image to be something else than the default, -you need to set the color type and bit depth you want in the LodePNGColorMode, -or the parameters colortype and bitdepth of the simple decoding function. - -If, when encoding, you use another color type than the default in the raw input -image, you need to specify its color type and bit depth in the LodePNGColorMode -of the raw image, or use the parameters colortype and bitdepth of the simple -encoding function. - -If, when encoding, you don't want LodePNG to choose the output PNG color type -but control it yourself, you need to set auto_convert in the encoder settings -to false, and specify the color type you want in the LodePNGInfo of the -encoder (including palette: it can generate a palette if auto_convert is true, -otherwise not). - -If the input and output color type differ (whether user chosen or auto chosen), -LodePNG will do a color conversion, which follows the rules below, and may -sometimes result in an error. - -To avoid some confusion: --the decoder converts from PNG to raw image --the encoder converts from raw image to PNG --the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image --the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG --when encoding, the color type in LodePNGInfo is ignored if auto_convert - is enabled, it is automatically generated instead --when decoding, the color type in LodePNGInfo is set by the decoder to that of the original - PNG image, but it can be ignored since the raw image has the color type you requested instead --if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion - between the color types is done if the color types are supported. If it is not - supported, an error is returned. If the types are the same, no conversion is done. --even though some conversions aren't supported, LodePNG supports loading PNGs from any - colortype and saving PNGs to any colortype, sometimes it just requires preparing - the raw image correctly before encoding. --both encoder and decoder use the same color converter. - -The function lodepng_convert does the color conversion. It is available in the -interface but normally isn't needed since the encoder and decoder already call -it. - -Non supported color conversions: --color to grayscale when non-gray pixels are present: no error is thrown, but -the result will look ugly because only the red channel is taken (it assumes all -three channels are the same in this case so ignores green and blue). The reason -no error is given is to allow converting from three-channel grayscale images to -one-channel even if there are numerical imprecisions. --anything to palette when the palette does not have an exact match for a from-color -in it: in this case an error is thrown - -Supported color conversions: --anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA --any gray or gray+alpha, to gray or gray+alpha --anything to a palette, as long as the palette has the requested colors in it --removing alpha channel --higher to smaller bitdepth, and vice versa - -If you want no color conversion to be done (e.g. for speed or control): --In the encoder, you can make it save a PNG with any color type by giving the -raw color mode and LodePNGInfo the same color mode, and setting auto_convert to -false. --In the decoder, you can make it store the pixel data in the same color type -as the PNG has, by setting the color_convert setting to false. Settings in -info_raw are then ignored. - -6.3. padding bits ------------------ - -In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines -have a bit amount that isn't a multiple of 8, then padding bits are used so that each -scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output. -The raw input image you give to the encoder, and the raw output image you get from the decoder -will NOT have these padding bits, e.g. in the case of a 1-bit image with a width -of 7 pixels, the first pixel of the second scanline will the 8th bit of the first byte, -not the first bit of a new byte. - -6.4. A note about 16-bits per channel and endianness ----------------------------------------------------- - -LodePNG uses unsigned char arrays for 16-bit per channel colors too, just like -for any other color format. The 16-bit values are stored in big endian (most -significant byte first) in these arrays. This is the opposite order of the -little endian used by x86 CPU's. - -LodePNG always uses big endian because the PNG file format does so internally. -Conversions to other formats than PNG uses internally are not supported by -LodePNG on purpose, there are myriads of formats, including endianness of 16-bit -colors, the order in which you store R, G, B and A, and so on. Supporting and -converting to/from all that is outside the scope of LodePNG. - -This may mean that, depending on your use case, you may want to convert the big -endian output of LodePNG to little endian with a for loop. This is certainly not -always needed, many applications and libraries support big endian 16-bit colors -anyway, but it means you cannot simply cast the unsigned char* buffer to an -unsigned short* buffer on x86 CPUs. - - -7. error values ---------------- - -All functions in LodePNG that return an error code, return 0 if everything went -OK, or a non-zero code if there was an error. - -The meaning of the LodePNG error values can be retrieved with the function -lodepng_error_text: given the numerical error code, it returns a description -of the error in English as a string. - -Check the implementation of lodepng_error_text to see the meaning of each code. - - -8. chunks and PNG editing -------------------------- - -If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG -editor that should follow the rules about handling of unknown chunks, or if your -program is able to read other types of chunks than the ones handled by LodePNG, -then that's possible with the chunk functions of LodePNG. - -A PNG chunk has the following layout: - -4 bytes length -4 bytes type name -length bytes data -4 bytes CRC - -8.1. iterating through chunks ------------------------------ - -If you have a buffer containing the PNG image data, then the first chunk (the -IHDR chunk) starts at byte number 8 of that buffer. The first 8 bytes are the -signature of the PNG and are not part of a chunk. But if you start at byte 8 -then you have a chunk, and can check the following things of it. - -NOTE: none of these functions check for memory buffer boundaries. To avoid -exploits, always make sure the buffer contains all the data of the chunks. -When using lodepng_chunk_next, make sure the returned value is within the -allocated memory. - -unsigned lodepng_chunk_length(const unsigned char* chunk): - -Get the length of the chunk's data. The total chunk length is this length + 12. - -void lodepng_chunk_type(char type[5], const unsigned char* chunk): -unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type): - -Get the type of the chunk or compare if it's a certain type - -unsigned char lodepng_chunk_critical(const unsigned char* chunk): -unsigned char lodepng_chunk_private(const unsigned char* chunk): -unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk): - -Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are). -Check if the chunk is private (public chunks are part of the standard, private ones not). -Check if the chunk is safe to copy. If it's not, then, when modifying data in a critical -chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your -program doesn't handle that type of unknown chunk. - -unsigned char* lodepng_chunk_data(unsigned char* chunk): -const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk): - -Get a pointer to the start of the data of the chunk. - -unsigned lodepng_chunk_check_crc(const unsigned char* chunk): -void lodepng_chunk_generate_crc(unsigned char* chunk): - -Check if the crc is correct or generate a correct one. - -unsigned char* lodepng_chunk_next(unsigned char* chunk): -const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk): - -Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these -functions do no boundary checking of the allocated data whatsoever, so make sure there is enough -data available in the buffer to be able to go to the next chunk. - -unsigned lodepng_chunk_append(unsigned char** out, size_t* outlength, const unsigned char* chunk): -unsigned lodepng_chunk_create(unsigned char** out, size_t* outlength, unsigned length, - const char* type, const unsigned char* data): - -These functions are used to create new chunks that are appended to the data in *out that has -length *outlength. The append function appends an existing chunk to the new data. The create -function creates a new chunk with the given parameters and appends it. Type is the 4-letter -name of the chunk. - -8.2. chunks in info_png ------------------------ - -The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3 -buffers (each with size) to contain 3 types of unknown chunks: -the ones that come before the PLTE chunk, the ones that come between the PLTE -and the IDAT chunks, and the ones that come after the IDAT chunks. -It's necessary to make the distinction between these 3 cases because the PNG -standard forces to keep the ordering of unknown chunks compared to the critical -chunks, but does not force any other ordering rules. - -info_png.unknown_chunks_data[0] is the chunks before PLTE -info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT -info_png.unknown_chunks_data[2] is the chunks after IDAT - -The chunks in these 3 buffers can be iterated through and read by using the same -way described in the previous subchapter. - -When using the decoder to decode a PNG, you can make it store all unknown chunks -if you set the option settings.remember_unknown_chunks to 1. By default, this -option is off (0). - -The encoder will always encode unknown chunks that are stored in the info_png. -If you need it to add a particular chunk that isn't known by LodePNG, you can -use lodepng_chunk_append or lodepng_chunk_create to the chunk data in -info_png.unknown_chunks_data[x]. - -Chunks that are known by LodePNG should not be added in that way. E.g. to make -LodePNG add a bKGD chunk, set background_defined to true and add the correct -parameters there instead. - - -9. compiler support -------------------- - -No libraries other than the current standard C library are needed to compile -LodePNG. For the C++ version, only the standard C++ library is needed on top. -Add the files lodepng.c(pp) and lodepng.h to your project, include -lodepng.h where needed, and your program can read/write PNG files. - -It is compatible with C90 and up, and C++03 and up. - -If performance is important, use optimization when compiling! For both the -encoder and decoder, this makes a large difference. - -Make sure that LodePNG is compiled with the same compiler of the same version -and with the same settings as the rest of the program, or the interfaces with -std::vectors and std::strings in C++ can be incompatible. - -CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. - -*) gcc and g++ - -LodePNG is developed in gcc so this compiler is natively supported. It gives no -warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++ -version 4.7.1 on Linux, 32-bit and 64-bit. - -*) Clang - -Fully supported and warning-free. - -*) Mingw - -The Mingw compiler (a port of gcc for Windows) should be fully supported by -LodePNG. - -*) Visual Studio and Visual C++ Express Edition - -LodePNG should be warning-free with warning level W4. Two warnings were disabled -with pragmas though: warning 4244 about implicit conversions, and warning 4996 -where it wants to use a non-standard function fopen_s instead of the standard C -fopen. - -Visual Studio may want "stdafx.h" files to be included in each source file and -give an error "unexpected end of file while looking for precompiled header". -This is not standard C++ and will not be added to the stock LodePNG. You can -disable it for lodepng.cpp only by right clicking it, Properties, C/C++, -Precompiled Headers, and set it to Not Using Precompiled Headers there. - -NOTE: Modern versions of VS should be fully supported, but old versions, e.g. -VS6, are not guaranteed to work. - -*) Compilers on Macintosh - -LodePNG has been reported to work both with gcc and LLVM for Macintosh, both for -C and C++. - -*) Other Compilers - -If you encounter problems on any compilers, feel free to let me know and I may -try to fix it if the compiler is modern and standards compliant. - - -10. examples ------------- - -This decoder example shows the most basic usage of LodePNG. More complex -examples can be found on the LodePNG website. - -10.1. decoder C++ example -------------------------- - -#include "lodepng.h" -#include - -int main(int argc, char *argv[]) { - const char* filename = argc > 1 ? argv[1] : "test.png"; - - //load and decode - std::vector image; - unsigned width, height; - unsigned error = lodepng::decode(image, width, height, filename); - - //if there's an error, display it - if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; - - //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... -} - -10.2. decoder C example ------------------------ - -#include "lodepng.h" - -int main(int argc, char *argv[]) { - unsigned error; - unsigned char* image; - size_t width, height; - const char* filename = argc > 1 ? argv[1] : "test.png"; - - error = lodepng_decode32_file(&image, &width, &height, filename); - - if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error)); - - / * use image here * / - - free(image); - return 0; -} - -11. state settings reference ----------------------------- - -A quick reference of some settings to set on the LodePNGState - -For decoding: - -state.decoder.zlibsettings.ignore_adler32: ignore ADLER32 checksums -state.decoder.zlibsettings.custom_...: use custom inflate function -state.decoder.ignore_crc: ignore CRC checksums -state.decoder.ignore_critical: ignore unknown critical chunks -state.decoder.ignore_end: ignore missing IEND chunk. May fail if this corruption causes other errors -state.decoder.color_convert: convert internal PNG color to chosen one -state.decoder.read_text_chunks: whether to read in text metadata chunks -state.decoder.remember_unknown_chunks: whether to read in unknown chunks -state.info_raw.colortype: desired color type for decoded image -state.info_raw.bitdepth: desired bit depth for decoded image -state.info_raw....: more color settings, see struct LodePNGColorMode -state.info_png....: no settings for decoder but ouput, see struct LodePNGInfo - -For encoding: - -state.encoder.zlibsettings.btype: disable compression by setting it to 0 -state.encoder.zlibsettings.use_lz77: use LZ77 in compression -state.encoder.zlibsettings.windowsize: tweak LZ77 windowsize -state.encoder.zlibsettings.minmatch: tweak min LZ77 length to match -state.encoder.zlibsettings.nicematch: tweak LZ77 match where to stop searching -state.encoder.zlibsettings.lazymatching: try one more LZ77 matching -state.encoder.zlibsettings.custom_...: use custom deflate function -state.encoder.auto_convert: choose optimal PNG color type, if 0 uses info_png -state.encoder.filter_palette_zero: PNG filter strategy for palette -state.encoder.filter_strategy: PNG filter strategy to encode with -state.encoder.force_palette: add palette even if not encoding to one -state.encoder.add_id: add LodePNG identifier and version as a text chunk -state.encoder.text_compression: use compressed text chunks for metadata -state.info_raw.colortype: color type of raw input image you provide -state.info_raw.bitdepth: bit depth of raw input image you provide -state.info_raw: more color settings, see struct LodePNGColorMode -state.info_png.color.colortype: desired color type if auto_convert is false -state.info_png.color.bitdepth: desired bit depth if auto_convert is false -state.info_png.color....: more color settings, see struct LodePNGColorMode -state.info_png....: more PNG related settings, see struct LodePNGInfo - - -12. changes ------------ - -The version number of LodePNG is the date of the change given in the format -yyyymmdd. - -Some changes aren't backwards compatible. Those are indicated with a (!) -symbol. - -Not all changes are listed here, the commit history in github lists more: -https://github.com/lvandeve/lodepng - -*) 14 aug 2019: around 25% faster decoding thanks to huffman lookup tables. -*) 15 jun 2019 (!): auto_choose_color API changed (for bugfix: don't use palette - if gray ICC profile) and non-ICC LodePNGColorProfile renamed to LodePNGColorStats. -*) 30 dec 2018: code style changes only: removed newlines before opening braces. -*) 10 sep 2018: added way to inspect metadata chunks without full decoding. -*) 19 aug 2018 (!): fixed color mode bKGD is encoded with and made it use - palette index in case of palette. -*) 10 aug 2018 (!): added support for gAMA, cHRM, sRGB and iCCP chunks. This - change is backwards compatible unless you relied on unknown_chunks for those. -*) 11 jun 2018: less restrictive check for pixel size integer overflow -*) 14 jan 2018: allow optionally ignoring a few more recoverable errors -*) 17 sep 2017: fix memory leak for some encoder input error cases -*) 27 nov 2016: grey+alpha auto color model detection bugfix -*) 18 apr 2016: Changed qsort to custom stable sort (for platforms w/o qsort). -*) 09 apr 2016: Fixed colorkey usage detection, and better file loading (within - the limits of pure C90). -*) 08 dec 2015: Made load_file function return error if file can't be opened. -*) 24 okt 2015: Bugfix with decoding to palette output. -*) 18 apr 2015: Boundary PM instead of just package-merge for faster encoding. -*) 24 aug 2014: Moved to github -*) 23 aug 2014: Reduced needless memory usage of decoder. -*) 28 jun 2014: Removed fix_png setting, always support palette OOB for - simplicity. Made ColorProfile public. -*) 09 jun 2014: Faster encoder by fixing hash bug and more zeros optimization. -*) 22 dec 2013: Power of two windowsize required for optimization. -*) 15 apr 2013: Fixed bug with LAC_ALPHA and color key. -*) 25 mar 2013: Added an optional feature to ignore some PNG errors (fix_png). -*) 11 mar 2013 (!): Bugfix with custom free. Changed from "my" to "lodepng_" - prefix for the custom allocators and made it possible with a new #define to - use custom ones in your project without needing to change lodepng's code. -*) 28 jan 2013: Bugfix with color key. -*) 27 okt 2012: Tweaks in text chunk keyword length error handling. -*) 8 okt 2012 (!): Added new filter strategy (entropy) and new auto color mode. - (no palette). Better deflate tree encoding. New compression tweak settings. - Faster color conversions while decoding. Some internal cleanups. -*) 23 sep 2012: Reduced warnings in Visual Studio a little bit. -*) 1 sep 2012 (!): Removed #define's for giving custom (de)compression functions - and made it work with function pointers instead. -*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc - and free functions and toggle #defines from compiler flags. Small fixes. -*) 6 may 2012 (!): Made plugging in custom zlib/deflate functions more flexible. -*) 22 apr 2012 (!): Made interface more consistent, renaming a lot. Removed - redundant C++ codec classes. Reduced amount of structs. Everything changed, - but it is cleaner now imho and functionality remains the same. Also fixed - several bugs and shrunk the implementation code. Made new samples. -*) 6 nov 2011 (!): By default, the encoder now automatically chooses the best - PNG color model and bit depth, based on the amount and type of colors of the - raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. -*) 9 okt 2011: simpler hash chain implementation for the encoder. -*) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching. -*) 23 aug 2011: tweaked the zlib compression parameters after benchmarking. - A bug with the PNG filtertype heuristic was fixed, so that it chooses much - better ones (it's quite significant). A setting to do an experimental, slow, - brute force search for PNG filter types is added. -*) 17 aug 2011 (!): changed some C zlib related function names. -*) 16 aug 2011: made the code less wide (max 120 characters per line). -*) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors. -*) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled. -*) 11 dec 2010: encoding is made faster, based on suggestion by Peter Eastman - to optimize long sequences of zeros. -*) 13 nov 2010: added LodePNG_InfoColor_hasPaletteAlpha and - LodePNG_InfoColor_canHaveAlpha functions for convenience. -*) 7 nov 2010: added LodePNG_error_text function to get error code description. -*) 30 okt 2010: made decoding slightly faster -*) 26 okt 2010: (!) changed some C function and struct names (more consistent). - Reorganized the documentation and the declaration order in the header. -*) 08 aug 2010: only changed some comments and external samples. -*) 05 jul 2010: fixed bug thanks to warnings in the new gcc version. -*) 14 mar 2010: fixed bug where too much memory was allocated for char buffers. -*) 02 sep 2008: fixed bug where it could create empty tree that linux apps could - read by ignoring the problem but windows apps couldn't. -*) 06 jun 2008: added more error checks for out of memory cases. -*) 26 apr 2008: added a few more checks here and there to ensure more safety. -*) 06 mar 2008: crash with encoding of strings fixed -*) 02 feb 2008: support for international text chunks added (iTXt) -*) 23 jan 2008: small cleanups, and #defines to divide code in sections -*) 20 jan 2008: support for unknown chunks allowing using LodePNG for an editor. -*) 18 jan 2008: support for tIME and pHYs chunks added to encoder and decoder. -*) 17 jan 2008: ability to encode and decode compressed zTXt chunks added - Also various fixes, such as in the deflate and the padding bits code. -*) 13 jan 2008: Added ability to encode Adam7-interlaced images. Improved - filtering code of encoder. -*) 07 jan 2008: (!) changed LodePNG to use ISO C90 instead of C++. A - C++ wrapper around this provides an interface almost identical to before. - Having LodePNG be pure ISO C90 makes it more portable. The C and C++ code - are together in these files but it works both for C and C++ compilers. -*) 29 dec 2007: (!) changed most integer types to unsigned int + other tweaks -*) 30 aug 2007: bug fixed which makes this Borland C++ compatible -*) 09 aug 2007: some VS2005 warnings removed again -*) 21 jul 2007: deflate code placed in new namespace separate from zlib code -*) 08 jun 2007: fixed bug with 2- and 4-bit color, and small interlaced images -*) 04 jun 2007: improved support for Visual Studio 2005: crash with accessing - invalid std::vector element [0] fixed, and level 3 and 4 warnings removed -*) 02 jun 2007: made the encoder add a tag with version by default -*) 27 may 2007: zlib and png code separated (but still in the same file), - simple encoder/decoder functions added for more simple usage cases -*) 19 may 2007: minor fixes, some code cleaning, new error added (error 69), - moved some examples from here to lodepng_examples.cpp -*) 12 may 2007: palette decoding bug fixed -*) 24 apr 2007: changed the license from BSD to the zlib license -*) 11 mar 2007: very simple addition: ability to encode bKGD chunks. -*) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding - palettized PNG images. Plus little interface change with palette and texts. -*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. - Fixed a bug where the end code of a block had length 0 in the Huffman tree. -*) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented - and supported by the encoder, resulting in smaller PNGs at the output. -*) 27 jan 2007: Made the Adler-32 test faster so that a timewaste is gone. -*) 24 jan 2007: gave encoder an error interface. Added color conversion from any - greyscale type to 8-bit greyscale with or without alpha. -*) 21 jan 2007: (!) Totally changed the interface. It allows more color types - to convert to and is more uniform. See the manual for how it works now. -*) 07 jan 2007: Some cleanup & fixes, and a few changes over the last days: - encode/decode custom tEXt chunks, separate classes for zlib & deflate, and - at last made the decoder give errors for incorrect Adler32 or Crc. -*) 01 jan 2007: Fixed bug with encoding PNGs with less than 8 bits per channel. -*) 29 dec 2006: Added support for encoding images without alpha channel, and - cleaned out code as well as making certain parts faster. -*) 28 dec 2006: Added "Settings" to the encoder. -*) 26 dec 2006: The encoder now does LZ77 encoding and produces much smaller files now. - Removed some code duplication in the decoder. Fixed little bug in an example. -*) 09 dec 2006: (!) Placed output parameters of public functions as first parameter. - Fixed a bug of the decoder with 16-bit per color. -*) 15 okt 2006: Changed documentation structure -*) 09 okt 2006: Encoder class added. It encodes a valid PNG image from the - given image buffer, however for now it's not compressed. -*) 08 sep 2006: (!) Changed to interface with a Decoder class -*) 30 jul 2006: (!) LodePNG_InfoPng , width and height are now retrieved in different - way. Renamed decodePNG to decodePNGGeneric. -*) 29 jul 2006: (!) Changed the interface: image info is now returned as a - struct of type LodePNG::LodePNG_Info, instead of a vector, which was a bit clumsy. -*) 28 jul 2006: Cleaned the code and added new error checks. - Corrected terminology "deflate" into "inflate". -*) 23 jun 2006: Added SDL example in the documentation in the header, this - example allows easy debugging by displaying the PNG and its transparency. -*) 22 jun 2006: (!) Changed way to obtain error value. Added - loadFile function for convenience. Made decodePNG32 faster. -*) 21 jun 2006: (!) Changed type of info vector to unsigned. - Changed position of palette in info vector. Fixed an important bug that - happened on PNGs with an uncompressed block. -*) 16 jun 2006: Internally changed unsigned into unsigned where - needed, and performed some optimizations. -*) 07 jun 2006: (!) Renamed functions to decodePNG and placed them - in LodePNG namespace. Changed the order of the parameters. Rewrote the - documentation in the header. Renamed files to lodepng.cpp and lodepng.h -*) 22 apr 2006: Optimized and improved some code -*) 07 sep 2005: (!) Changed to std::vector interface -*) 12 aug 2005: Initial release (C++, decoder only) - - -13. contact information ------------------------ - -Feel free to contact me with suggestions, problems, comments, ... concerning -LodePNG. If you encounter a PNG image that doesn't work properly with this -decoder, feel free to send it and I'll use it to find and fix the problem. - -My email address is (puzzle the account and domain together with an @ symbol): -Domain: gmail dot com. -Account: lode dot vandevenne. - - -Copyright (c) 2005-2019 Lode Vandevenne -*/ +/* +LodePNG version 20200306 + +Copyright (c) 2005-2020 Lode Vandevenne + +This software is provided 'as-is', without any express or implied +warranty. In no event will the authors be held liable for any damages +arising from the use of this software. + +Permission is granted to anyone to use this software for any purpose, +including commercial applications, and to alter it and redistribute it +freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + + 3. This notice may not be removed or altered from any source + distribution. +*/ + +#ifndef LODEPNG_H +#define LODEPNG_H + +#include /*for size_t*/ + +extern const char* LODEPNG_VERSION_STRING; + +/* +The following #defines are used to create code sections. They can be disabled +to disable code sections, which can give faster compile time and smaller binary. +The "NO_COMPILE" defines are designed to be used to pass as defines to the +compiler command to disable them without modifying this header, e.g. +-DLODEPNG_NO_COMPILE_ZLIB for gcc. +In addition to those below, you can also define LODEPNG_NO_COMPILE_CRC to +allow implementing a custom lodepng_crc32. +*/ +/*deflate & zlib. If disabled, you must specify alternative zlib functions in +the custom_zlib field of the compress and decompress settings*/ +#ifndef LODEPNG_NO_COMPILE_ZLIB +#define LODEPNG_COMPILE_ZLIB +#endif + +/*png encoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_PNG +#define LODEPNG_COMPILE_PNG +#endif + +/*deflate&zlib decoder and png decoder*/ +#ifndef LODEPNG_NO_COMPILE_DECODER +#define LODEPNG_COMPILE_DECODER +#endif + +/*deflate&zlib encoder and png encoder*/ +#ifndef LODEPNG_NO_COMPILE_ENCODER +#define LODEPNG_COMPILE_ENCODER +#endif + +/*the optional built in harddisk file loading and saving functions*/ +#ifndef LODEPNG_NO_COMPILE_DISK +#define LODEPNG_COMPILE_DISK +#endif + +/*support for chunks other than IHDR, IDAT, PLTE, tRNS, IEND: ancillary and unknown chunks*/ +#ifndef LODEPNG_NO_COMPILE_ANCILLARY_CHUNKS +#define LODEPNG_COMPILE_ANCILLARY_CHUNKS +#endif + +/*ability to convert error numerical codes to English text string*/ +#ifndef LODEPNG_NO_COMPILE_ERROR_TEXT +#define LODEPNG_COMPILE_ERROR_TEXT +#endif + +/*Compile the default allocators (C's free, malloc and realloc). If you disable this, +you can define the functions lodepng_free, lodepng_malloc and lodepng_realloc in your +source files with custom allocators.*/ +#ifndef LODEPNG_NO_COMPILE_ALLOCATORS +#define LODEPNG_COMPILE_ALLOCATORS +#endif + +/*compile the C++ version (you can disable the C++ wrapper here even when compiling for C++)*/ +#ifdef __cplusplus +#ifndef LODEPNG_NO_COMPILE_CPP +#define LODEPNG_COMPILE_CPP +#endif +#endif + +#ifdef LODEPNG_COMPILE_CPP +#include +#include +#endif /*LODEPNG_COMPILE_CPP*/ + +#ifdef LODEPNG_COMPILE_PNG +/*The PNG color types (also used for raw image).*/ +typedef enum LodePNGColorType { + LCT_GREY = 0, /*grayscale: 1,2,4,8,16 bit*/ + LCT_RGB = 2, /*RGB: 8,16 bit*/ + LCT_PALETTE = 3, /*palette: 1,2,4,8 bit*/ + LCT_GREY_ALPHA = 4, /*grayscale with alpha: 8,16 bit*/ + LCT_RGBA = 6, /*RGB with alpha: 8,16 bit*/ + /*LCT_MAX_OCTET_VALUE lets the compiler allow this enum to represent any invalid + byte value from 0 to 255 that could be present in an invalid PNG file header. Do + not use, compare with or set the name LCT_MAX_OCTET_VALUE, instead either use + the valid color type names above, or numeric values like 1 or 7 when checking for + particular disallowed color type byte values, or cast to integer to print it.*/ + LCT_MAX_OCTET_VALUE = 255 +} LodePNGColorType; + +#ifdef LODEPNG_COMPILE_DECODER +/* +Converts PNG data in memory to raw pixel data. +out: Output parameter. Pointer to buffer that will contain the raw pixel data. + After decoding, its size is w * h * (bytes per pixel) bytes larger than + initially. Bytes per pixel depends on colortype and bitdepth. + Must be freed after usage with free(*out). + Note: for 16-bit per channel colors, uses big endian format like PNG does. +w: Output parameter. Pointer to width of pixel data. +h: Output parameter. Pointer to height of pixel data. +in: Memory buffer with the PNG file. +insize: size of the in buffer. +colortype: the desired color type for the raw output image. See explanation on PNG color types. +bitdepth: the desired bit depth for the raw output image. See explanation on PNG color types. +Return value: LodePNG error code (0 means no error). +*/ +unsigned lodepng_decode_memory(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_decode_memory, but always decodes to 32-bit RGBA raw image*/ +unsigned lodepng_decode32(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize); + +/*Same as lodepng_decode_memory, but always decodes to 24-bit RGB raw image*/ +unsigned lodepng_decode24(unsigned char** out, unsigned* w, unsigned* h, + const unsigned char* in, size_t insize); + +#ifdef LODEPNG_COMPILE_DISK +/* +Load PNG from disk, from file with given name. +Same as the other decode functions, but instead takes a filename as input. +*/ +unsigned lodepng_decode_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_decode_file, but always decodes to 32-bit RGBA raw image.*/ +unsigned lodepng_decode32_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); + +/*Same as lodepng_decode_file, but always decodes to 24-bit RGB raw image.*/ +unsigned lodepng_decode24_file(unsigned char** out, unsigned* w, unsigned* h, + const char* filename); +#endif /*LODEPNG_COMPILE_DISK*/ +#endif /*LODEPNG_COMPILE_DECODER*/ + + +#ifdef LODEPNG_COMPILE_ENCODER +/* +Converts raw pixel data into a PNG image in memory. The colortype and bitdepth + of the output PNG image cannot be chosen, they are automatically determined + by the colortype, bitdepth and content of the input pixel data. + Note: for 16-bit per channel colors, needs big endian format like PNG does. +out: Output parameter. Pointer to buffer that will contain the PNG image data. + Must be freed after usage with free(*out). +outsize: Output parameter. Pointer to the size in bytes of the out buffer. +image: The raw pixel data to encode. The size of this buffer should be + w * h * (bytes per pixel), bytes per pixel depends on colortype and bitdepth. +w: width of the raw pixel data in pixels. +h: height of the raw pixel data in pixels. +colortype: the color type of the raw input image. See explanation on PNG color types. +bitdepth: the bit depth of the raw input image. See explanation on PNG color types. +Return value: LodePNG error code (0 means no error). +*/ +unsigned lodepng_encode_memory(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_encode_memory, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); + +/*Same as lodepng_encode_memory, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h); + +#ifdef LODEPNG_COMPILE_DISK +/* +Converts raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! +*/ +unsigned lodepng_encode_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h, + LodePNGColorType colortype, unsigned bitdepth); + +/*Same as lodepng_encode_file, but always encodes from 32-bit RGBA raw image.*/ +unsigned lodepng_encode32_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); + +/*Same as lodepng_encode_file, but always encodes from 24-bit RGB raw image.*/ +unsigned lodepng_encode24_file(const char* filename, + const unsigned char* image, unsigned w, unsigned h); +#endif /*LODEPNG_COMPILE_DISK*/ +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +#ifdef LODEPNG_COMPILE_CPP +namespace lodepng { +#ifdef LODEPNG_COMPILE_DECODER +/*Same as lodepng_decode_memory, but decodes to an std::vector. The colortype +is the format to output the pixels to. Default is RGBA 8-bit per channel.*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const unsigned char* in, size_t insize, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::vector& in, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#ifdef LODEPNG_COMPILE_DISK +/* +Converts PNG file from disk to raw pixel data in memory. +Same as the other decode functions, but instead takes a filename as input. +*/ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + const std::string& filename, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#endif /* LODEPNG_COMPILE_DISK */ +#endif /* LODEPNG_COMPILE_DECODER */ + +#ifdef LODEPNG_COMPILE_ENCODER +/*Same as lodepng_encode_memory, but encodes to an std::vector. colortype +is that of the raw input data. The output PNG color type will be auto chosen.*/ +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#ifdef LODEPNG_COMPILE_DISK +/* +Converts 32-bit RGBA raw pixel data into a PNG file on disk. +Same as the other encode functions, but instead takes a filename as output. +NOTE: This overwrites existing files without warning! +*/ +unsigned encode(const std::string& filename, + const unsigned char* in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +unsigned encode(const std::string& filename, + const std::vector& in, unsigned w, unsigned h, + LodePNGColorType colortype = LCT_RGBA, unsigned bitdepth = 8); +#endif /* LODEPNG_COMPILE_DISK */ +#endif /* LODEPNG_COMPILE_ENCODER */ +} /* namespace lodepng */ +#endif /*LODEPNG_COMPILE_CPP*/ +#endif /*LODEPNG_COMPILE_PNG*/ + +#ifdef LODEPNG_COMPILE_ERROR_TEXT +/*Returns an English description of the numerical error code.*/ +const char* lodepng_error_text(unsigned code); +#endif /*LODEPNG_COMPILE_ERROR_TEXT*/ + +#ifdef LODEPNG_COMPILE_DECODER +/*Settings for zlib decompression*/ +typedef struct LodePNGDecompressSettings LodePNGDecompressSettings; +struct LodePNGDecompressSettings { + /* Check LodePNGDecoderSettings for more ignorable errors such as ignore_crc */ + unsigned ignore_adler32; /*if 1, continue and don't give an error message if the Adler32 checksum is corrupted*/ + unsigned ignore_nlen; /*ignore complement of len checksum in uncompressed blocks*/ + + /*use custom zlib decoder instead of built in one (default: null)*/ + unsigned (*custom_zlib)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGDecompressSettings*); + /*use custom deflate decoder instead of built in one (default: null) + if custom_zlib is not null, custom_inflate is ignored (the zlib format uses deflate)*/ + unsigned (*custom_inflate)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGDecompressSettings*); + + const void* custom_context; /*optional custom settings for custom functions*/ +}; + +extern const LodePNGDecompressSettings lodepng_default_decompress_settings; +void lodepng_decompress_settings_init(LodePNGDecompressSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/* +Settings for zlib compression. Tweaking these settings tweaks the balance +between speed and compression ratio. +*/ +typedef struct LodePNGCompressSettings LodePNGCompressSettings; +struct LodePNGCompressSettings /*deflate = compress*/ { + /*LZ77 related settings*/ + unsigned btype; /*the block type for LZ (0, 1, 2 or 3, see zlib standard). Should be 2 for proper compression.*/ + unsigned use_lz77; /*whether or not to use LZ77. Should be 1 for proper compression.*/ + unsigned windowsize; /*must be a power of two <= 32768. higher compresses more but is slower. Default value: 2048.*/ + unsigned minmatch; /*minimum lz77 length. 3 is normally best, 6 can be better for some PNGs. Default: 0*/ + unsigned nicematch; /*stop searching if >= this length found. Set to 258 for best compression. Default: 128*/ + unsigned lazymatching; /*use lazy matching: better compression but a bit slower. Default: true*/ + + /*use custom zlib encoder instead of built in one (default: null)*/ + unsigned (*custom_zlib)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGCompressSettings*); + /*use custom deflate encoder instead of built in one (default: null) + if custom_zlib is used, custom_deflate is ignored since only the built in + zlib function will call custom_deflate*/ + unsigned (*custom_deflate)(unsigned char**, size_t*, + const unsigned char*, size_t, + const LodePNGCompressSettings*); + + const void* custom_context; /*optional custom settings for custom functions*/ +}; + +extern const LodePNGCompressSettings lodepng_default_compress_settings; +void lodepng_compress_settings_init(LodePNGCompressSettings* settings); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#ifdef LODEPNG_COMPILE_PNG +/* +Color mode of an image. Contains all information required to decode the pixel +bits to RGBA colors. This information is the same as used in the PNG file +format, and is used both for PNG and raw image data in LodePNG. +*/ +typedef struct LodePNGColorMode { + /*header (IHDR)*/ + LodePNGColorType colortype; /*color type, see PNG standard or documentation further in this header file*/ + unsigned bitdepth; /*bits per sample, see PNG standard or documentation further in this header file*/ + + /* + palette (PLTE and tRNS) + + Dynamically allocated with the colors of the palette, including alpha. + This field may not be allocated directly, use lodepng_color_mode_init first, + then lodepng_palette_add per color to correctly initialize it (to ensure size + of exactly 1024 bytes). + + The alpha channels must be set as well, set them to 255 for opaque images. + + When decoding, by default you can ignore this palette, since LodePNG already + fills the palette colors in the pixels of the raw RGBA output. + + The palette is only supported for color type 3. + */ + unsigned char* palette; /*palette in RGBARGBA... order. Must be either 0, or when allocated must have 1024 bytes*/ + size_t palettesize; /*palette size in number of colors (amount of used bytes is 4 * palettesize)*/ + + /* + transparent color key (tRNS) + + This color uses the same bit depth as the bitdepth value in this struct, which can be 1-bit to 16-bit. + For grayscale PNGs, r, g and b will all 3 be set to the same. + + When decoding, by default you can ignore this information, since LodePNG sets + pixels with this key to transparent already in the raw RGBA output. + + The color key is only supported for color types 0 and 2. + */ + unsigned key_defined; /*is a transparent color key given? 0 = false, 1 = true*/ + unsigned key_r; /*red/grayscale component of color key*/ + unsigned key_g; /*green component of color key*/ + unsigned key_b; /*blue component of color key*/ +} LodePNGColorMode; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_color_mode_init(LodePNGColorMode* info); +void lodepng_color_mode_cleanup(LodePNGColorMode* info); +/*return value is error code (0 means no error)*/ +unsigned lodepng_color_mode_copy(LodePNGColorMode* dest, const LodePNGColorMode* source); +/* Makes a temporary LodePNGColorMode that does not need cleanup (no palette) */ +LodePNGColorMode lodepng_color_mode_make(LodePNGColorType colortype, unsigned bitdepth); + +void lodepng_palette_clear(LodePNGColorMode* info); +/*add 1 color to the palette*/ +unsigned lodepng_palette_add(LodePNGColorMode* info, + unsigned char r, unsigned char g, unsigned char b, unsigned char a); + +/*get the total amount of bits per pixel, based on colortype and bitdepth in the struct*/ +unsigned lodepng_get_bpp(const LodePNGColorMode* info); +/*get the amount of color channels used, based on colortype in the struct. +If a palette is used, it counts as 1 channel.*/ +unsigned lodepng_get_channels(const LodePNGColorMode* info); +/*is it a grayscale type? (only colortype 0 or 4)*/ +unsigned lodepng_is_greyscale_type(const LodePNGColorMode* info); +/*has it got an alpha channel? (only colortype 2 or 6)*/ +unsigned lodepng_is_alpha_type(const LodePNGColorMode* info); +/*has it got a palette? (only colortype 3)*/ +unsigned lodepng_is_palette_type(const LodePNGColorMode* info); +/*only returns true if there is a palette and there is a value in the palette with alpha < 255. +Loops through the palette to check this.*/ +unsigned lodepng_has_palette_alpha(const LodePNGColorMode* info); +/* +Check if the given color info indicates the possibility of having non-opaque pixels in the PNG image. +Returns true if the image can have translucent or invisible pixels (it still be opaque if it doesn't use such pixels). +Returns false if the image can only have opaque pixels. +In detail, it returns true only if it's a color type with alpha, or has a palette with non-opaque values, +or if "key_defined" is true. +*/ +unsigned lodepng_can_have_alpha(const LodePNGColorMode* info); +/*Returns the byte size of a raw image buffer with given width, height and color mode*/ +size_t lodepng_get_raw_size(unsigned w, unsigned h, const LodePNGColorMode* color); + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +/*The information of a Time chunk in PNG.*/ +typedef struct LodePNGTime { + unsigned year; /*2 bytes used (0-65535)*/ + unsigned month; /*1-12*/ + unsigned day; /*1-31*/ + unsigned hour; /*0-23*/ + unsigned minute; /*0-59*/ + unsigned second; /*0-60 (to allow for leap seconds)*/ +} LodePNGTime; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +/*Information about the PNG image, except pixels, width and height.*/ +typedef struct LodePNGInfo { + /*header (IHDR), palette (PLTE) and transparency (tRNS) chunks*/ + unsigned compression_method;/*compression method of the original file. Always 0.*/ + unsigned filter_method; /*filter method of the original file*/ + unsigned interlace_method; /*interlace method of the original file: 0=none, 1=Adam7*/ + LodePNGColorMode color; /*color type and bits, palette and transparency of the PNG file*/ + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /* + Suggested background color chunk (bKGD) + + This uses the same color mode and bit depth as the PNG (except no alpha channel), + with values truncated to the bit depth in the unsigned integer. + + For grayscale and palette PNGs, the value is stored in background_r. The values + in background_g and background_b are then unused. + + So when decoding, you may get these in a different color mode than the one you requested + for the raw pixels. + + When encoding with auto_convert, you must use the color model defined in info_png.color for + these values. The encoder normally ignores info_png.color when auto_convert is on, but will + use it to interpret these values (and convert copies of them to its chosen color model). + + When encoding, avoid setting this to an expensive color, such as a non-gray value + when the image is gray, or the compression will be worse since it will be forced to + write the PNG with a more expensive color mode (when auto_convert is on). + + The decoder does not use this background color to edit the color of pixels. This is a + completely optional metadata feature. + */ + unsigned background_defined; /*is a suggested background color given?*/ + unsigned background_r; /*red/gray/palette component of suggested background color*/ + unsigned background_g; /*green component of suggested background color*/ + unsigned background_b; /*blue component of suggested background color*/ + + /* + non-international text chunks (tEXt and zTXt) + + The char** arrays each contain num strings. The actual messages are in + text_strings, while text_keys are keywords that give a short description what + the actual text represents, e.g. Title, Author, Description, or anything else. + + All the string fields below including keys, names and language tags are null terminated. + The PNG specification uses null characters for the keys, names and tags, and forbids null + characters to appear in the main text which is why we can use null termination everywhere here. + + A keyword is minimum 1 character and maximum 79 characters long. It's + discouraged to use a single line length longer than 79 characters for texts. + + Don't allocate these text buffers yourself. Use the init/cleanup functions + correctly and use lodepng_add_text and lodepng_clear_text. + */ + size_t text_num; /*the amount of texts in these char** buffers (there may be more texts in itext)*/ + char** text_keys; /*the keyword of a text chunk (e.g. "Comment")*/ + char** text_strings; /*the actual text*/ + + /* + international text chunks (iTXt) + Similar to the non-international text chunks, but with additional strings + "langtags" and "transkeys". + */ + size_t itext_num; /*the amount of international texts in this PNG*/ + char** itext_keys; /*the English keyword of the text chunk (e.g. "Comment")*/ + char** itext_langtags; /*language tag for this text's language, ISO/IEC 646 string, e.g. ISO 639 language tag*/ + char** itext_transkeys; /*keyword translated to the international language - UTF-8 string*/ + char** itext_strings; /*the actual international text - UTF-8 string*/ + + /*time chunk (tIME)*/ + unsigned time_defined; /*set to 1 to make the encoder generate a tIME chunk*/ + LodePNGTime time; + + /*phys chunk (pHYs)*/ + unsigned phys_defined; /*if 0, there is no pHYs chunk and the values below are undefined, if 1 else there is one*/ + unsigned phys_x; /*pixels per unit in x direction*/ + unsigned phys_y; /*pixels per unit in y direction*/ + unsigned phys_unit; /*may be 0 (unknown unit) or 1 (metre)*/ + + /* + Color profile related chunks: gAMA, cHRM, sRGB, iCPP + + LodePNG does not apply any color conversions on pixels in the encoder or decoder and does not interpret these color + profile values. It merely passes on the information. If you wish to use color profiles and convert colors, please + use these values with a color management library. + + See the PNG, ICC and sRGB specifications for more information about the meaning of these values. + */ + + /* gAMA chunk: optional, overridden by sRGB or iCCP if those are present. */ + unsigned gama_defined; /* Whether a gAMA chunk is present (0 = not present, 1 = present). */ + unsigned gama_gamma; /* Gamma exponent times 100000 */ + + /* cHRM chunk: optional, overridden by sRGB or iCCP if those are present. */ + unsigned chrm_defined; /* Whether a cHRM chunk is present (0 = not present, 1 = present). */ + unsigned chrm_white_x; /* White Point x times 100000 */ + unsigned chrm_white_y; /* White Point y times 100000 */ + unsigned chrm_red_x; /* Red x times 100000 */ + unsigned chrm_red_y; /* Red y times 100000 */ + unsigned chrm_green_x; /* Green x times 100000 */ + unsigned chrm_green_y; /* Green y times 100000 */ + unsigned chrm_blue_x; /* Blue x times 100000 */ + unsigned chrm_blue_y; /* Blue y times 100000 */ + + /* + sRGB chunk: optional. May not appear at the same time as iCCP. + If gAMA is also present gAMA must contain value 45455. + If cHRM is also present cHRM must contain respectively 31270,32900,64000,33000,30000,60000,15000,6000. + */ + unsigned srgb_defined; /* Whether an sRGB chunk is present (0 = not present, 1 = present). */ + unsigned srgb_intent; /* Rendering intent: 0=perceptual, 1=rel. colorimetric, 2=saturation, 3=abs. colorimetric */ + + /* + iCCP chunk: optional. May not appear at the same time as sRGB. + + LodePNG does not parse or use the ICC profile (except its color space header field for an edge case), a + separate library to handle the ICC data (not included in LodePNG) format is needed to use it for color + management and conversions. + + For encoding, if iCCP is present, gAMA and cHRM are recommended to be added as well with values that match the ICC + profile as closely as possible, if you wish to do this you should provide the correct values for gAMA and cHRM and + enable their '_defined' flags since LodePNG will not automatically compute them from the ICC profile. + + For encoding, the ICC profile is required by the PNG specification to be an "RGB" profile for non-gray + PNG color types and a "GRAY" profile for gray PNG color types. If you disable auto_convert, you must ensure + the ICC profile type matches your requested color type, else the encoder gives an error. If auto_convert is + enabled (the default), and the ICC profile is not a good match for the pixel data, this will result in an encoder + error if the pixel data has non-gray pixels for a GRAY profile, or a silent less-optimal compression of the pixel + data if the pixels could be encoded as grayscale but the ICC profile is RGB. + + To avoid this do not set an ICC profile in the image unless there is a good reason for it, and when doing so + make sure you compute it carefully to avoid the above problems. + */ + unsigned iccp_defined; /* Whether an iCCP chunk is present (0 = not present, 1 = present). */ + char* iccp_name; /* Null terminated string with profile name, 1-79 bytes */ + /* + The ICC profile in iccp_profile_size bytes. + Don't allocate this buffer yourself. Use the init/cleanup functions + correctly and use lodepng_set_icc and lodepng_clear_icc. + */ + unsigned char* iccp_profile; + unsigned iccp_profile_size; /* The size of iccp_profile in bytes */ + + /* End of color profile related chunks */ + + + /* + unknown chunks: chunks not known by LodePNG, passed on byte for byte. + + There are 3 buffers, one for each position in the PNG where unknown chunks can appear. + Each buffer contains all unknown chunks for that position consecutively. + The 3 positions are: + 0: between IHDR and PLTE, 1: between PLTE and IDAT, 2: between IDAT and IEND. + + For encoding, do not store critical chunks or known chunks that are enabled with a "_defined" flag + above in here, since the encoder will blindly follow this and could then encode an invalid PNG file + (such as one with two IHDR chunks or the disallowed combination of sRGB with iCCP). But do use + this if you wish to store an ancillary chunk that is not supported by LodePNG (such as sPLT or hIST), + or any non-standard PNG chunk. + + Do not allocate or traverse this data yourself. Use the chunk traversing functions declared + later, such as lodepng_chunk_next and lodepng_chunk_append, to read/write this struct. + */ + unsigned char* unknown_chunks_data[3]; + size_t unknown_chunks_size[3]; /*size in bytes of the unknown chunks, given for protection*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGInfo; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_info_init(LodePNGInfo* info); +void lodepng_info_cleanup(LodePNGInfo* info); +/*return value is error code (0 means no error)*/ +unsigned lodepng_info_copy(LodePNGInfo* dest, const LodePNGInfo* source); + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS +unsigned lodepng_add_text(LodePNGInfo* info, const char* key, const char* str); /*push back both texts at once*/ +void lodepng_clear_text(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ + +unsigned lodepng_add_itext(LodePNGInfo* info, const char* key, const char* langtag, + const char* transkey, const char* str); /*push back the 4 texts of 1 chunk at once*/ +void lodepng_clear_itext(LodePNGInfo* info); /*use this to clear the itexts again after you filled them in*/ + +/*replaces if exists*/ +unsigned lodepng_set_icc(LodePNGInfo* info, const char* name, const unsigned char* profile, unsigned profile_size); +void lodepng_clear_icc(LodePNGInfo* info); /*use this to clear the texts again after you filled them in*/ +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ + +/* +Converts raw buffer from one color type to another color type, based on +LodePNGColorMode structs to describe the input and output color type. +See the reference manual at the end of this header file to see which color conversions are supported. +return value = LodePNG error code (0 if all went ok, an error if the conversion isn't supported) +The out buffer must have size (w * h * bpp + 7) / 8, where bpp is the bits per pixel +of the output color type (lodepng_get_bpp). +For < 8 bpp images, there should not be padding bits at the end of scanlines. +For 16-bit per channel colors, uses big endian format like PNG does. +Return value is LodePNG error code +*/ +unsigned lodepng_convert(unsigned char* out, const unsigned char* in, + const LodePNGColorMode* mode_out, const LodePNGColorMode* mode_in, + unsigned w, unsigned h); + +#ifdef LODEPNG_COMPILE_DECODER +/* +Settings for the decoder. This contains settings for the PNG and the Zlib +decoder, but not the Info settings from the Info structs. +*/ +typedef struct LodePNGDecoderSettings { + LodePNGDecompressSettings zlibsettings; /*in here is the setting to ignore Adler32 checksums*/ + + /* Check LodePNGDecompressSettings for more ignorable errors such as ignore_adler32 */ + unsigned ignore_crc; /*ignore CRC checksums*/ + unsigned ignore_critical; /*ignore unknown critical chunks*/ + unsigned ignore_end; /*ignore issues at end of file if possible (missing IEND chunk, too large chunk, ...)*/ + /* TODO: make a system involving warnings with levels and a strict mode instead. Other potentially recoverable + errors: srgb rendering intent value, size of content of ancillary chunks, more than 79 characters for some + strings, placement/combination rules for ancillary chunks, crc of unknown chunks, allowed characters + in string keys, etc... */ + + unsigned color_convert; /*whether to convert the PNG to the color type you want. Default: yes*/ + +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + unsigned read_text_chunks; /*if false but remember_unknown_chunks is true, they're stored in the unknown chunks*/ + /*store all bytes from unknown chunks in the LodePNGInfo (off by default, useful for a png editor)*/ + unsigned remember_unknown_chunks; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGDecoderSettings; + +void lodepng_decoder_settings_init(LodePNGDecoderSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/*automatically use color type with less bits per pixel if losslessly possible. Default: AUTO*/ +typedef enum LodePNGFilterStrategy { + /*every filter at zero*/ + LFS_ZERO = 0, + /*every filter at 1, 2, 3 or 4 (paeth), unlike LFS_ZERO not a good choice, but for testing*/ + LFS_ONE = 1, + LFS_TWO = 2, + LFS_THREE = 3, + LFS_FOUR = 4, + /*Use filter that gives minimum sum, as described in the official PNG filter heuristic.*/ + LFS_MINSUM, + /*Use the filter type that gives smallest Shannon entropy for this scanline. Depending + on the image, this is better or worse than minsum.*/ + LFS_ENTROPY, + /* + Brute-force-search PNG filters by compressing each filter for each scanline. + Experimental, very slow, and only rarely gives better compression than MINSUM. + */ + LFS_BRUTE_FORCE, + /*use predefined_filters buffer: you specify the filter type for each scanline*/ + LFS_PREDEFINED +} LodePNGFilterStrategy; + +/*Gives characteristics about the integer RGBA colors of the image (count, alpha channel usage, bit depth, ...), +which helps decide which color model to use for encoding. +Used internally by default if "auto_convert" is enabled. Public because it's useful for custom algorithms.*/ +typedef struct LodePNGColorStats { + unsigned colored; /*not grayscale*/ + unsigned key; /*image is not opaque and color key is possible instead of full alpha*/ + unsigned short key_r; /*key values, always as 16-bit, in 8-bit case the byte is duplicated, e.g. 65535 means 255*/ + unsigned short key_g; + unsigned short key_b; + unsigned alpha; /*image is not opaque and alpha channel or alpha palette required*/ + unsigned numcolors; /*amount of colors, up to 257. Not valid if bits == 16 or allow_palette is disabled.*/ + unsigned char palette[1024]; /*Remembers up to the first 256 RGBA colors, in no particular order, only valid when numcolors is valid*/ + unsigned bits; /*bits per channel (not for palette). 1,2 or 4 for grayscale only. 16 if 16-bit per channel required.*/ + size_t numpixels; + + /*user settings for computing/using the stats*/ + unsigned allow_palette; /*default 1. if 0, disallow choosing palette colortype in auto_choose_color, and don't count numcolors*/ + unsigned allow_greyscale; /*default 1. if 0, choose RGB or RGBA even if the image only has gray colors*/ +} LodePNGColorStats; + +void lodepng_color_stats_init(LodePNGColorStats* stats); + +/*Get a LodePNGColorStats of the image. The stats must already have been inited. +Returns error code (e.g. alloc fail) or 0 if ok.*/ +unsigned lodepng_compute_color_stats(LodePNGColorStats* stats, + const unsigned char* image, unsigned w, unsigned h, + const LodePNGColorMode* mode_in); + +/*Settings for the encoder.*/ +typedef struct LodePNGEncoderSettings { + LodePNGCompressSettings zlibsettings; /*settings for the zlib encoder, such as window size, ...*/ + + unsigned auto_convert; /*automatically choose output PNG color type. Default: true*/ + + /*If true, follows the official PNG heuristic: if the PNG uses a palette or lower than + 8 bit depth, set all filters to zero. Otherwise use the filter_strategy. Note that to + completely follow the official PNG heuristic, filter_palette_zero must be true and + filter_strategy must be LFS_MINSUM*/ + unsigned filter_palette_zero; + /*Which filter strategy to use when not using zeroes due to filter_palette_zero. + Set filter_palette_zero to 0 to ensure always using your chosen strategy. Default: LFS_MINSUM*/ + LodePNGFilterStrategy filter_strategy; + /*used if filter_strategy is LFS_PREDEFINED. In that case, this must point to a buffer with + the same length as the amount of scanlines in the image, and each value must <= 5. You + have to cleanup this buffer, LodePNG will never free it. Don't forget that filter_palette_zero + must be set to 0 to ensure this is also used on palette or low bitdepth images.*/ + const unsigned char* predefined_filters; + + /*force creating a PLTE chunk if colortype is 2 or 6 (= a suggested palette). + If colortype is 3, PLTE is _always_ created.*/ + unsigned force_palette; +#ifdef LODEPNG_COMPILE_ANCILLARY_CHUNKS + /*add LodePNG identifier and version as a text chunk, for debugging*/ + unsigned add_id; + /*encode text chunks as zTXt chunks instead of tEXt chunks, and use compression in iTXt chunks*/ + unsigned text_compression; +#endif /*LODEPNG_COMPILE_ANCILLARY_CHUNKS*/ +} LodePNGEncoderSettings; + +void lodepng_encoder_settings_init(LodePNGEncoderSettings* settings); +#endif /*LODEPNG_COMPILE_ENCODER*/ + + +#if defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) +/*The settings, state and information for extended encoding and decoding.*/ +typedef struct LodePNGState { +#ifdef LODEPNG_COMPILE_DECODER + LodePNGDecoderSettings decoder; /*the decoding settings*/ +#endif /*LODEPNG_COMPILE_DECODER*/ +#ifdef LODEPNG_COMPILE_ENCODER + LodePNGEncoderSettings encoder; /*the encoding settings*/ +#endif /*LODEPNG_COMPILE_ENCODER*/ + LodePNGColorMode info_raw; /*specifies the format in which you would like to get the raw pixel buffer*/ + LodePNGInfo info_png; /*info of the PNG image obtained after decoding*/ + unsigned error; +} LodePNGState; + +/*init, cleanup and copy functions to use with this struct*/ +void lodepng_state_init(LodePNGState* state); +void lodepng_state_cleanup(LodePNGState* state); +void lodepng_state_copy(LodePNGState* dest, const LodePNGState* source); +#endif /* defined(LODEPNG_COMPILE_DECODER) || defined(LODEPNG_COMPILE_ENCODER) */ + +#ifdef LODEPNG_COMPILE_DECODER +/* +Same as lodepng_decode_memory, but uses a LodePNGState to allow custom settings and +getting much more information about the PNG image and color mode. +*/ +unsigned lodepng_decode(unsigned char** out, unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); + +/* +Read the PNG header, but not the actual data. This returns only the information +that is in the IHDR chunk of the PNG, such as width, height and color type. The +information is placed in the info_png field of the LodePNGState. +*/ +unsigned lodepng_inspect(unsigned* w, unsigned* h, + LodePNGState* state, + const unsigned char* in, size_t insize); +#endif /*LODEPNG_COMPILE_DECODER*/ + +/* +Reads one metadata chunk (other than IHDR) of the PNG file and outputs what it +read in the state. Returns error code on failure. +Use lodepng_inspect first with a new state, then e.g. lodepng_chunk_find_const +to find the desired chunk type, and if non null use lodepng_inspect_chunk (with +chunk_pointer - start_of_file as pos). +Supports most metadata chunks from the PNG standard (gAMA, bKGD, tEXt, ...). +Ignores unsupported, unknown, non-metadata or IHDR chunks (without error). +Requirements: &in[pos] must point to start of a chunk, must use regular +lodepng_inspect first since format of most other chunks depends on IHDR, and if +there is a PLTE chunk, that one must be inspected before tRNS or bKGD. +*/ +unsigned lodepng_inspect_chunk(LodePNGState* state, size_t pos, + const unsigned char* in, size_t insize); + +#ifdef LODEPNG_COMPILE_ENCODER +/*This function allocates the out buffer with standard malloc and stores the size in *outsize.*/ +unsigned lodepng_encode(unsigned char** out, size_t* outsize, + const unsigned char* image, unsigned w, unsigned h, + LodePNGState* state); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +/* +The lodepng_chunk functions are normally not needed, except to traverse the +unknown chunks stored in the LodePNGInfo struct, or add new ones to it. +It also allows traversing the chunks of an encoded PNG file yourself. + +The chunk pointer always points to the beginning of the chunk itself, that is +the first byte of the 4 length bytes. + +In the PNG file format, chunks have the following format: +-4 bytes length: length of the data of the chunk in bytes (chunk itself is 12 bytes longer) +-4 bytes chunk type (ASCII a-z,A-Z only, see below) +-length bytes of data (may be 0 bytes if length was 0) +-4 bytes of CRC, computed on chunk name + data + +The first chunk starts at the 8th byte of the PNG file, the entire rest of the file +exists out of concatenated chunks with the above format. + +PNG standard chunk ASCII naming conventions: +-First byte: uppercase = critical, lowercase = ancillary +-Second byte: uppercase = public, lowercase = private +-Third byte: must be uppercase +-Fourth byte: uppercase = unsafe to copy, lowercase = safe to copy +*/ + +/* +Gets the length of the data of the chunk. Total chunk length has 12 bytes more. +There must be at least 4 bytes to read from. If the result value is too large, +it may be corrupt data. +*/ +unsigned lodepng_chunk_length(const unsigned char* chunk); + +/*puts the 4-byte type in null terminated string*/ +void lodepng_chunk_type(char type[5], const unsigned char* chunk); + +/*check if the type is the given type*/ +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type); + +/*0: it's one of the critical chunk types, 1: it's an ancillary chunk (see PNG standard)*/ +unsigned char lodepng_chunk_ancillary(const unsigned char* chunk); + +/*0: public, 1: private (see PNG standard)*/ +unsigned char lodepng_chunk_private(const unsigned char* chunk); + +/*0: the chunk is unsafe to copy, 1: the chunk is safe to copy (see PNG standard)*/ +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk); + +/*get pointer to the data of the chunk, where the input points to the header of the chunk*/ +unsigned char* lodepng_chunk_data(unsigned char* chunk); +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk); + +/*returns 0 if the crc is correct, 1 if it's incorrect (0 for OK as usual!)*/ +unsigned lodepng_chunk_check_crc(const unsigned char* chunk); + +/*generates the correct CRC from the data and puts it in the last 4 bytes of the chunk*/ +void lodepng_chunk_generate_crc(unsigned char* chunk); + +/* +Iterate to next chunks, allows iterating through all chunks of the PNG file. +Input must be at the beginning of a chunk (result of a previous lodepng_chunk_next call, +or the 8th byte of a PNG file which always has the first chunk), or alternatively may +point to the first byte of the PNG file (which is not a chunk but the magic header, the +function will then skip over it and return the first real chunk). +Will output pointer to the start of the next chunk, or at or beyond end of the file if there +is no more chunk after this or possibly if the chunk is corrupt. +Start this process at the 8th byte of the PNG file. +In a non-corrupt PNG file, the last chunk should have name "IEND". +*/ +unsigned char* lodepng_chunk_next(unsigned char* chunk, unsigned char* end); +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk, const unsigned char* end); + +/*Finds the first chunk with the given type in the range [chunk, end), or returns NULL if not found.*/ +unsigned char* lodepng_chunk_find(unsigned char* chunk, unsigned char* end, const char type[5]); +const unsigned char* lodepng_chunk_find_const(const unsigned char* chunk, const unsigned char* end, const char type[5]); + +/* +Appends chunk to the data in out. The given chunk should already have its chunk header. +The out variable and outsize are updated to reflect the new reallocated buffer. +Returns error code (0 if it went ok) +*/ +unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk); + +/* +Appends new chunk to out. The chunk to append is given by giving its length, type +and data separately. The type is a 4-letter string. +The out variable and outsize are updated to reflect the new reallocated buffer. +Returne error code (0 if it went ok) +*/ +unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, unsigned length, + const char* type, const unsigned char* data); + + +/*Calculate CRC32 of buffer*/ +unsigned lodepng_crc32(const unsigned char* buf, size_t len); +#endif /*LODEPNG_COMPILE_PNG*/ + + +#ifdef LODEPNG_COMPILE_ZLIB +/* +This zlib part can be used independently to zlib compress and decompress a +buffer. It cannot be used to create gzip files however, and it only supports the +part of zlib that is required for PNG, it does not support dictionaries. +*/ + +#ifdef LODEPNG_COMPILE_DECODER +/*Inflate a buffer. Inflate is the decompression step of deflate. Out buffer must be freed after use.*/ +unsigned lodepng_inflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); + +/* +Decompresses Zlib data. Reallocates the out buffer and appends the data. The +data must be according to the zlib specification. +Either, *out must be NULL and *outsize must be 0, or, *out must be a valid +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_decompress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGDecompressSettings* settings); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/* +Compresses data with Zlib. Reallocates the out buffer and appends the data. +Zlib adds a small header and trailer around the deflate data. +The data is output in the format of the zlib specification. +Either, *out must be NULL and *outsize must be 0, or, *out must be a valid +buffer and *outsize its size in bytes. out must be freed by user after usage. +*/ +unsigned lodepng_zlib_compress(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +/* +Find length-limited Huffman code for given frequencies. This function is in the +public interface only for tests, it's used internally by lodepng_deflate. +*/ +unsigned lodepng_huffman_code_lengths(unsigned* lengths, const unsigned* frequencies, + size_t numcodes, unsigned maxbitlen); + +/*Compress a buffer with deflate. See RFC 1951. Out buffer must be freed after use.*/ +unsigned lodepng_deflate(unsigned char** out, size_t* outsize, + const unsigned char* in, size_t insize, + const LodePNGCompressSettings* settings); + +#endif /*LODEPNG_COMPILE_ENCODER*/ +#endif /*LODEPNG_COMPILE_ZLIB*/ + +#ifdef LODEPNG_COMPILE_DISK +/* +Load a file from disk into buffer. The function allocates the out buffer, and +after usage you should free it. +out: output parameter, contains pointer to loaded buffer. +outsize: output parameter, size of the allocated out buffer +filename: the path to the file to load +return value: error code (0 means ok) +*/ +unsigned lodepng_load_file(unsigned char** out, size_t* outsize, const char* filename); + +/* +Save a file from buffer to disk. Warning, if it exists, this function overwrites +the file without warning! +buffer: the buffer to write +buffersize: size of the buffer to write +filename: the path to the file to save to +return value: error code (0 means ok) +*/ +unsigned lodepng_save_file(const unsigned char* buffer, size_t buffersize, const char* filename); +#endif /*LODEPNG_COMPILE_DISK*/ + +#ifdef LODEPNG_COMPILE_CPP +/* The LodePNG C++ wrapper uses std::vectors instead of manually allocated memory buffers. */ +namespace lodepng { +#ifdef LODEPNG_COMPILE_PNG +class State : public LodePNGState { + public: + State(); + State(const State& other); + ~State(); + State& operator=(const State& other); +}; + +#ifdef LODEPNG_COMPILE_DECODER +/* Same as other lodepng::decode, but using a State for more settings and information. */ +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const unsigned char* in, size_t insize); +unsigned decode(std::vector& out, unsigned& w, unsigned& h, + State& state, + const std::vector& in); +#endif /*LODEPNG_COMPILE_DECODER*/ + +#ifdef LODEPNG_COMPILE_ENCODER +/* Same as other lodepng::encode, but using a State for more settings and information. */ +unsigned encode(std::vector& out, + const unsigned char* in, unsigned w, unsigned h, + State& state); +unsigned encode(std::vector& out, + const std::vector& in, unsigned w, unsigned h, + State& state); +#endif /*LODEPNG_COMPILE_ENCODER*/ + +#ifdef LODEPNG_COMPILE_DISK +/* +Load a file from disk into an std::vector. +return value: error code (0 means ok) +*/ +unsigned load_file(std::vector& buffer, const std::string& filename); + +/* +Save the binary data in an std::vector to a file on disk. The file is overwritten +without warning. +*/ +unsigned save_file(const std::vector& buffer, const std::string& filename); +#endif /* LODEPNG_COMPILE_DISK */ +#endif /* LODEPNG_COMPILE_PNG */ + +#ifdef LODEPNG_COMPILE_ZLIB +#ifdef LODEPNG_COMPILE_DECODER +/* Zlib-decompress an unsigned char buffer */ +unsigned decompress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); + +/* Zlib-decompress an std::vector */ +unsigned decompress(std::vector& out, const std::vector& in, + const LodePNGDecompressSettings& settings = lodepng_default_decompress_settings); +#endif /* LODEPNG_COMPILE_DECODER */ + +#ifdef LODEPNG_COMPILE_ENCODER +/* Zlib-compress an unsigned char buffer */ +unsigned compress(std::vector& out, const unsigned char* in, size_t insize, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); + +/* Zlib-compress an std::vector */ +unsigned compress(std::vector& out, const std::vector& in, + const LodePNGCompressSettings& settings = lodepng_default_compress_settings); +#endif /* LODEPNG_COMPILE_ENCODER */ +#endif /* LODEPNG_COMPILE_ZLIB */ +} /* namespace lodepng */ +#endif /*LODEPNG_COMPILE_CPP*/ + +/* +TODO: +[.] test if there are no memory leaks or security exploits - done a lot but needs to be checked often +[.] check compatibility with various compilers - done but needs to be redone for every newer version +[X] converting color to 16-bit per channel types +[X] support color profile chunk types (but never let them touch RGB values by default) +[ ] support all public PNG chunk types (almost done except sBIT, sPLT and hIST) +[ ] make sure encoder generates no chunks with size > (2^31)-1 +[ ] partial decoding (stream processing) +[X] let the "isFullyOpaque" function check color keys and transparent palettes too +[X] better name for the variables "codes", "codesD", "codelengthcodes", "clcl" and "lldl" +[ ] allow treating some errors like warnings, when image is recoverable (e.g. 69, 57, 58) +[ ] make warnings like: oob palette, checksum fail, data after iend, wrong/unknown crit chunk, no null terminator in text, ... +[ ] error messages with line numbers (and version) +[ ] errors in state instead of as return code? +[ ] new errors/warnings like suspiciously big decompressed ztxt or iccp chunk +[ ] let the C++ wrapper catch exceptions coming from the standard library and return LodePNG error codes +[ ] allow user to provide custom color conversion functions, e.g. for premultiplied alpha, padding bits or not, ... +[ ] allow user to give data (void*) to custom allocator +[X] provide alternatives for C library functions not present on some platforms (memcpy, ...) +*/ + +#endif /*LODEPNG_H inclusion guard*/ + +/* +LodePNG Documentation +--------------------- + +0. table of contents +-------------------- + + 1. about + 1.1. supported features + 1.2. features not supported + 2. C and C++ version + 3. security + 4. decoding + 5. encoding + 6. color conversions + 6.1. PNG color types + 6.2. color conversions + 6.3. padding bits + 6.4. A note about 16-bits per channel and endianness + 7. error values + 8. chunks and PNG editing + 9. compiler support + 10. examples + 10.1. decoder C++ example + 10.2. decoder C example + 11. state settings reference + 12. changes + 13. contact information + + +1. about +-------- + +PNG is a file format to store raster images losslessly with good compression, +supporting different color types and alpha channel. + +LodePNG is a PNG codec according to the Portable Network Graphics (PNG) +Specification (Second Edition) - W3C Recommendation 10 November 2003. + +The specifications used are: + +*) Portable Network Graphics (PNG) Specification (Second Edition): + http://www.w3.org/TR/2003/REC-PNG-20031110 +*) RFC 1950 ZLIB Compressed Data Format version 3.3: + http://www.gzip.org/zlib/rfc-zlib.html +*) RFC 1951 DEFLATE Compressed Data Format Specification ver 1.3: + http://www.gzip.org/zlib/rfc-deflate.html + +The most recent version of LodePNG can currently be found at +http://lodev.org/lodepng/ + +LodePNG works both in C (ISO C90) and C++, with a C++ wrapper that adds +extra functionality. + +LodePNG exists out of two files: +-lodepng.h: the header file for both C and C++ +-lodepng.c(pp): give it the name lodepng.c or lodepng.cpp (or .cc) depending on your usage + +If you want to start using LodePNG right away without reading this doc, get the +examples from the LodePNG website to see how to use it in code, or check the +smaller examples in chapter 13 here. + +LodePNG is simple but only supports the basic requirements. To achieve +simplicity, the following design choices were made: There are no dependencies +on any external library. There are functions to decode and encode a PNG with +a single function call, and extended versions of these functions taking a +LodePNGState struct allowing to specify or get more information. By default +the colors of the raw image are always RGB or RGBA, no matter what color type +the PNG file uses. To read and write files, there are simple functions to +convert the files to/from buffers in memory. + +This all makes LodePNG suitable for loading textures in games, demos and small +programs, ... It's less suitable for full fledged image editors, loading PNGs +over network (it requires all the image data to be available before decoding can +begin), life-critical systems, ... + +1.1. supported features +----------------------- + +The following features are supported by the decoder: + +*) decoding of PNGs with any color type, bit depth and interlace mode, to a 24- or 32-bit color raw image, + or the same color type as the PNG +*) encoding of PNGs, from any raw image to 24- or 32-bit color, or the same color type as the raw image +*) Adam7 interlace and deinterlace for any color type +*) loading the image from harddisk or decoding it from a buffer from other sources than harddisk +*) support for alpha channels, including RGBA color model, translucent palettes and color keying +*) zlib decompression (inflate) +*) zlib compression (deflate) +*) CRC32 and ADLER32 checksums +*) colorimetric color profile conversions: currently experimentally available in lodepng_util.cpp only, + plus alternatively ability to pass on chroma/gamma/ICC profile information to other color management system. +*) handling of unknown chunks, allowing making a PNG editor that stores custom and unknown chunks. +*) the following chunks are supported by both encoder and decoder: + IHDR: header information + PLTE: color palette + IDAT: pixel data + IEND: the final chunk + tRNS: transparency for palettized images + tEXt: textual information + zTXt: compressed textual information + iTXt: international textual information + bKGD: suggested background color + pHYs: physical dimensions + tIME: modification time + cHRM: RGB chromaticities + gAMA: RGB gamma correction + iCCP: ICC color profile + sRGB: rendering intent + +1.2. features not supported +--------------------------- + +The following features are _not_ supported: + +*) some features needed to make a conformant PNG-Editor might be still missing. +*) partial loading/stream processing. All data must be available and is processed in one call. +*) The following public chunks are not (yet) supported but treated as unknown chunks by LodePNG: + sBIT + hIST + sPLT + + +2. C and C++ version +-------------------- + +The C version uses buffers allocated with alloc that you need to free() +yourself. You need to use init and cleanup functions for each struct whenever +using a struct from the C version to avoid exploits and memory leaks. + +The C++ version has extra functions with std::vectors in the interface and the +lodepng::State class which is a LodePNGState with constructor and destructor. + +These files work without modification for both C and C++ compilers because all +the additional C++ code is in "#ifdef __cplusplus" blocks that make C-compilers +ignore it, and the C code is made to compile both with strict ISO C90 and C++. + +To use the C++ version, you need to rename the source file to lodepng.cpp +(instead of lodepng.c), and compile it with a C++ compiler. + +To use the C version, you need to rename the source file to lodepng.c (instead +of lodepng.cpp), and compile it with a C compiler. + + +3. Security +----------- + +Even if carefully designed, it's always possible that LodePNG contains possible +exploits. If you discover one, please let me know, and it will be fixed. + +When using LodePNG, care has to be taken with the C version of LodePNG, as well +as the C-style structs when working with C++. The following conventions are used +for all C-style structs: + +-if a struct has a corresponding init function, always call the init function when making a new one +-if a struct has a corresponding cleanup function, call it before the struct disappears to avoid memory leaks +-if a struct has a corresponding copy function, use the copy function instead of "=". + The destination must also be inited already. + + +4. Decoding +----------- + +Decoding converts a PNG compressed image to a raw pixel buffer. + +Most documentation on using the decoder is at its declarations in the header +above. For C, simple decoding can be done with functions such as +lodepng_decode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_decode. For C++, all decoding can be done with the +various lodepng::decode functions, and lodepng::State can be used for advanced +features. + +When using the LodePNGState, it uses the following fields for decoding: +*) LodePNGInfo info_png: it stores extra information about the PNG (the input) in here +*) LodePNGColorMode info_raw: here you can say what color mode of the raw image (the output) you want to get +*) LodePNGDecoderSettings decoder: you can specify a few extra settings for the decoder to use + +LodePNGInfo info_png +-------------------- + +After decoding, this contains extra information of the PNG image, except the actual +pixels, width and height because these are already gotten directly from the decoder +functions. + +It contains for example the original color type of the PNG image, text comments, +suggested background color, etc... More details about the LodePNGInfo struct are +at its declaration documentation. + +LodePNGColorMode info_raw +------------------------- + +When decoding, here you can specify which color type you want +the resulting raw image to be. If this is different from the colortype of the +PNG, then the decoder will automatically convert the result. This conversion +always works, except if you want it to convert a color PNG to grayscale or to +a palette with missing colors. + +By default, 32-bit color is used for the result. + +LodePNGDecoderSettings decoder +------------------------------ + +The settings can be used to ignore the errors created by invalid CRC and Adler32 +chunks, and to disable the decoding of tEXt chunks. + +There's also a setting color_convert, true by default. If false, no conversion +is done, the resulting data will be as it was in the PNG (after decompression) +and you'll have to puzzle the colors of the pixels together yourself using the +color type information in the LodePNGInfo. + + +5. Encoding +----------- + +Encoding converts a raw pixel buffer to a PNG compressed image. + +Most documentation on using the encoder is at its declarations in the header +above. For C, simple encoding can be done with functions such as +lodepng_encode32, and more advanced decoding can be done with the struct +LodePNGState and lodepng_encode. For C++, all encoding can be done with the +various lodepng::encode functions, and lodepng::State can be used for advanced +features. + +Like the decoder, the encoder can also give errors. However it gives less errors +since the encoder input is trusted, the decoder input (a PNG image that could +be forged by anyone) is not trusted. + +When using the LodePNGState, it uses the following fields for encoding: +*) LodePNGInfo info_png: here you specify how you want the PNG (the output) to be. +*) LodePNGColorMode info_raw: here you say what color type of the raw image (the input) has +*) LodePNGEncoderSettings encoder: you can specify a few settings for the encoder to use + +LodePNGInfo info_png +-------------------- + +When encoding, you use this the opposite way as when decoding: for encoding, +you fill in the values you want the PNG to have before encoding. By default it's +not needed to specify a color type for the PNG since it's automatically chosen, +but it's possible to choose it yourself given the right settings. + +The encoder will not always exactly match the LodePNGInfo struct you give, +it tries as close as possible. Some things are ignored by the encoder. The +encoder uses, for example, the following settings from it when applicable: +colortype and bitdepth, text chunks, time chunk, the color key, the palette, the +background color, the interlace method, unknown chunks, ... + +When encoding to a PNG with colortype 3, the encoder will generate a PLTE chunk. +If the palette contains any colors for which the alpha channel is not 255 (so +there are translucent colors in the palette), it'll add a tRNS chunk. + +LodePNGColorMode info_raw +------------------------- + +You specify the color type of the raw image that you give to the input here, +including a possible transparent color key and palette you happen to be using in +your raw image data. + +By default, 32-bit color is assumed, meaning your input has to be in RGBA +format with 4 bytes (unsigned chars) per pixel. + +LodePNGEncoderSettings encoder +------------------------------ + +The following settings are supported (some are in sub-structs): +*) auto_convert: when this option is enabled, the encoder will +automatically choose the smallest possible color mode (including color key) that +can encode the colors of all pixels without information loss. +*) btype: the block type for LZ77. 0 = uncompressed, 1 = fixed huffman tree, + 2 = dynamic huffman tree (best compression). Should be 2 for proper + compression. +*) use_lz77: whether or not to use LZ77 for compressed block types. Should be + true for proper compression. +*) windowsize: the window size used by the LZ77 encoder (1 - 32768). Has value + 2048 by default, but can be set to 32768 for better, but slow, compression. +*) force_palette: if colortype is 2 or 6, you can make the encoder write a PLTE + chunk if force_palette is true. This can used as suggested palette to convert + to by viewers that don't support more than 256 colors (if those still exist) +*) add_id: add text chunk "Encoder: LodePNG " to the image. +*) text_compression: default 1. If 1, it'll store texts as zTXt instead of tEXt chunks. + zTXt chunks use zlib compression on the text. This gives a smaller result on + large texts but a larger result on small texts (such as a single program name). + It's all tEXt or all zTXt though, there's no separate setting per text yet. + + +6. color conversions +-------------------- + +An important thing to note about LodePNG, is that the color type of the PNG, and +the color type of the raw image, are completely independent. By default, when +you decode a PNG, you get the result as a raw image in the color type you want, +no matter whether the PNG was encoded with a palette, grayscale or RGBA color. +And if you encode an image, by default LodePNG will automatically choose the PNG +color type that gives good compression based on the values of colors and amount +of colors in the image. It can be configured to let you control it instead as +well, though. + +To be able to do this, LodePNG does conversions from one color mode to another. +It can convert from almost any color type to any other color type, except the +following conversions: RGB to grayscale is not supported, and converting to a +palette when the palette doesn't have a required color is not supported. This is +not supported on purpose: this is information loss which requires a color +reduction algorithm that is beyond the scope of a PNG encoder (yes, RGB to gray +is easy, but there are multiple ways if you want to give some channels more +weight). + +By default, when decoding, you get the raw image in 32-bit RGBA or 24-bit RGB +color, no matter what color type the PNG has. And by default when encoding, +LodePNG automatically picks the best color model for the output PNG, and expects +the input image to be 32-bit RGBA or 24-bit RGB. So, unless you want to control +the color format of the images yourself, you can skip this chapter. + +6.1. PNG color types +-------------------- + +A PNG image can have many color types, ranging from 1-bit color to 64-bit color, +as well as palettized color modes. After the zlib decompression and unfiltering +in the PNG image is done, the raw pixel data will have that color type and thus +a certain amount of bits per pixel. If you want the output raw image after +decoding to have another color type, a conversion is done by LodePNG. + +The PNG specification gives the following color types: + +0: grayscale, bit depths 1, 2, 4, 8, 16 +2: RGB, bit depths 8 and 16 +3: palette, bit depths 1, 2, 4 and 8 +4: grayscale with alpha, bit depths 8 and 16 +6: RGBA, bit depths 8 and 16 + +Bit depth is the amount of bits per pixel per color channel. So the total amount +of bits per pixel is: amount of channels * bitdepth. + +6.2. color conversions +---------------------- + +As explained in the sections about the encoder and decoder, you can specify +color types and bit depths in info_png and info_raw to change the default +behaviour. + +If, when decoding, you want the raw image to be something else than the default, +you need to set the color type and bit depth you want in the LodePNGColorMode, +or the parameters colortype and bitdepth of the simple decoding function. + +If, when encoding, you use another color type than the default in the raw input +image, you need to specify its color type and bit depth in the LodePNGColorMode +of the raw image, or use the parameters colortype and bitdepth of the simple +encoding function. + +If, when encoding, you don't want LodePNG to choose the output PNG color type +but control it yourself, you need to set auto_convert in the encoder settings +to false, and specify the color type you want in the LodePNGInfo of the +encoder (including palette: it can generate a palette if auto_convert is true, +otherwise not). + +If the input and output color type differ (whether user chosen or auto chosen), +LodePNG will do a color conversion, which follows the rules below, and may +sometimes result in an error. + +To avoid some confusion: +-the decoder converts from PNG to raw image +-the encoder converts from raw image to PNG +-the colortype and bitdepth in LodePNGColorMode info_raw, are those of the raw image +-the colortype and bitdepth in the color field of LodePNGInfo info_png, are those of the PNG +-when encoding, the color type in LodePNGInfo is ignored if auto_convert + is enabled, it is automatically generated instead +-when decoding, the color type in LodePNGInfo is set by the decoder to that of the original + PNG image, but it can be ignored since the raw image has the color type you requested instead +-if the color type of the LodePNGColorMode and PNG image aren't the same, a conversion + between the color types is done if the color types are supported. If it is not + supported, an error is returned. If the types are the same, no conversion is done. +-even though some conversions aren't supported, LodePNG supports loading PNGs from any + colortype and saving PNGs to any colortype, sometimes it just requires preparing + the raw image correctly before encoding. +-both encoder and decoder use the same color converter. + +The function lodepng_convert does the color conversion. It is available in the +interface but normally isn't needed since the encoder and decoder already call +it. + +Non supported color conversions: +-color to grayscale when non-gray pixels are present: no error is thrown, but +the result will look ugly because only the red channel is taken (it assumes all +three channels are the same in this case so ignores green and blue). The reason +no error is given is to allow converting from three-channel grayscale images to +one-channel even if there are numerical imprecisions. +-anything to palette when the palette does not have an exact match for a from-color +in it: in this case an error is thrown + +Supported color conversions: +-anything to 8-bit RGB, 8-bit RGBA, 16-bit RGB, 16-bit RGBA +-any gray or gray+alpha, to gray or gray+alpha +-anything to a palette, as long as the palette has the requested colors in it +-removing alpha channel +-higher to smaller bitdepth, and vice versa + +If you want no color conversion to be done (e.g. for speed or control): +-In the encoder, you can make it save a PNG with any color type by giving the +raw color mode and LodePNGInfo the same color mode, and setting auto_convert to +false. +-In the decoder, you can make it store the pixel data in the same color type +as the PNG has, by setting the color_convert setting to false. Settings in +info_raw are then ignored. + +6.3. padding bits +----------------- + +In the PNG file format, if a less than 8-bit per pixel color type is used and the scanlines +have a bit amount that isn't a multiple of 8, then padding bits are used so that each +scanline starts at a fresh byte. But that is NOT true for the LodePNG raw input and output. +The raw input image you give to the encoder, and the raw output image you get from the decoder +will NOT have these padding bits, e.g. in the case of a 1-bit image with a width +of 7 pixels, the first pixel of the second scanline will the 8th bit of the first byte, +not the first bit of a new byte. + +6.4. A note about 16-bits per channel and endianness +---------------------------------------------------- + +LodePNG uses unsigned char arrays for 16-bit per channel colors too, just like +for any other color format. The 16-bit values are stored in big endian (most +significant byte first) in these arrays. This is the opposite order of the +little endian used by x86 CPU's. + +LodePNG always uses big endian because the PNG file format does so internally. +Conversions to other formats than PNG uses internally are not supported by +LodePNG on purpose, there are myriads of formats, including endianness of 16-bit +colors, the order in which you store R, G, B and A, and so on. Supporting and +converting to/from all that is outside the scope of LodePNG. + +This may mean that, depending on your use case, you may want to convert the big +endian output of LodePNG to little endian with a for loop. This is certainly not +always needed, many applications and libraries support big endian 16-bit colors +anyway, but it means you cannot simply cast the unsigned char* buffer to an +unsigned short* buffer on x86 CPUs. + + +7. error values +--------------- + +All functions in LodePNG that return an error code, return 0 if everything went +OK, or a non-zero code if there was an error. + +The meaning of the LodePNG error values can be retrieved with the function +lodepng_error_text: given the numerical error code, it returns a description +of the error in English as a string. + +Check the implementation of lodepng_error_text to see the meaning of each code. + + +8. chunks and PNG editing +------------------------- + +If you want to add extra chunks to a PNG you encode, or use LodePNG for a PNG +editor that should follow the rules about handling of unknown chunks, or if your +program is able to read other types of chunks than the ones handled by LodePNG, +then that's possible with the chunk functions of LodePNG. + +A PNG chunk has the following layout: + +4 bytes length +4 bytes type name +length bytes data +4 bytes CRC + +8.1. iterating through chunks +----------------------------- + +If you have a buffer containing the PNG image data, then the first chunk (the +IHDR chunk) starts at byte number 8 of that buffer. The first 8 bytes are the +signature of the PNG and are not part of a chunk. But if you start at byte 8 +then you have a chunk, and can check the following things of it. + +NOTE: none of these functions check for memory buffer boundaries. To avoid +exploits, always make sure the buffer contains all the data of the chunks. +When using lodepng_chunk_next, make sure the returned value is within the +allocated memory. + +unsigned lodepng_chunk_length(const unsigned char* chunk): + +Get the length of the chunk's data. The total chunk length is this length + 12. + +void lodepng_chunk_type(char type[5], const unsigned char* chunk): +unsigned char lodepng_chunk_type_equals(const unsigned char* chunk, const char* type): + +Get the type of the chunk or compare if it's a certain type + +unsigned char lodepng_chunk_critical(const unsigned char* chunk): +unsigned char lodepng_chunk_private(const unsigned char* chunk): +unsigned char lodepng_chunk_safetocopy(const unsigned char* chunk): + +Check if the chunk is critical in the PNG standard (only IHDR, PLTE, IDAT and IEND are). +Check if the chunk is private (public chunks are part of the standard, private ones not). +Check if the chunk is safe to copy. If it's not, then, when modifying data in a critical +chunk, unsafe to copy chunks of the old image may NOT be saved in the new one if your +program doesn't handle that type of unknown chunk. + +unsigned char* lodepng_chunk_data(unsigned char* chunk): +const unsigned char* lodepng_chunk_data_const(const unsigned char* chunk): + +Get a pointer to the start of the data of the chunk. + +unsigned lodepng_chunk_check_crc(const unsigned char* chunk): +void lodepng_chunk_generate_crc(unsigned char* chunk): + +Check if the crc is correct or generate a correct one. + +unsigned char* lodepng_chunk_next(unsigned char* chunk): +const unsigned char* lodepng_chunk_next_const(const unsigned char* chunk): + +Iterate to the next chunk. This works if you have a buffer with consecutive chunks. Note that these +functions do no boundary checking of the allocated data whatsoever, so make sure there is enough +data available in the buffer to be able to go to the next chunk. + +unsigned lodepng_chunk_append(unsigned char** out, size_t* outsize, const unsigned char* chunk): +unsigned lodepng_chunk_create(unsigned char** out, size_t* outsize, unsigned length, + const char* type, const unsigned char* data): + +These functions are used to create new chunks that are appended to the data in *out that has +length *outsize. The append function appends an existing chunk to the new data. The create +function creates a new chunk with the given parameters and appends it. Type is the 4-letter +name of the chunk. + +8.2. chunks in info_png +----------------------- + +The LodePNGInfo struct contains fields with the unknown chunk in it. It has 3 +buffers (each with size) to contain 3 types of unknown chunks: +the ones that come before the PLTE chunk, the ones that come between the PLTE +and the IDAT chunks, and the ones that come after the IDAT chunks. +It's necessary to make the distinction between these 3 cases because the PNG +standard forces to keep the ordering of unknown chunks compared to the critical +chunks, but does not force any other ordering rules. + +info_png.unknown_chunks_data[0] is the chunks before PLTE +info_png.unknown_chunks_data[1] is the chunks after PLTE, before IDAT +info_png.unknown_chunks_data[2] is the chunks after IDAT + +The chunks in these 3 buffers can be iterated through and read by using the same +way described in the previous subchapter. + +When using the decoder to decode a PNG, you can make it store all unknown chunks +if you set the option settings.remember_unknown_chunks to 1. By default, this +option is off (0). + +The encoder will always encode unknown chunks that are stored in the info_png. +If you need it to add a particular chunk that isn't known by LodePNG, you can +use lodepng_chunk_append or lodepng_chunk_create to the chunk data in +info_png.unknown_chunks_data[x]. + +Chunks that are known by LodePNG should not be added in that way. E.g. to make +LodePNG add a bKGD chunk, set background_defined to true and add the correct +parameters there instead. + + +9. compiler support +------------------- + +No libraries other than the current standard C library are needed to compile +LodePNG. For the C++ version, only the standard C++ library is needed on top. +Add the files lodepng.c(pp) and lodepng.h to your project, include +lodepng.h where needed, and your program can read/write PNG files. + +It is compatible with C90 and up, and C++03 and up. + +If performance is important, use optimization when compiling! For both the +encoder and decoder, this makes a large difference. + +Make sure that LodePNG is compiled with the same compiler of the same version +and with the same settings as the rest of the program, or the interfaces with +std::vectors and std::strings in C++ can be incompatible. + +CHAR_BITS must be 8 or higher, because LodePNG uses unsigned chars for octets. + +*) gcc and g++ + +LodePNG is developed in gcc so this compiler is natively supported. It gives no +warnings with compiler options "-Wall -Wextra -pedantic -ansi", with gcc and g++ +version 4.7.1 on Linux, 32-bit and 64-bit. + +*) Clang + +Fully supported and warning-free. + +*) Mingw + +The Mingw compiler (a port of gcc for Windows) should be fully supported by +LodePNG. + +*) Visual Studio and Visual C++ Express Edition + +LodePNG should be warning-free with warning level W4. Two warnings were disabled +with pragmas though: warning 4244 about implicit conversions, and warning 4996 +where it wants to use a non-standard function fopen_s instead of the standard C +fopen. + +Visual Studio may want "stdafx.h" files to be included in each source file and +give an error "unexpected end of file while looking for precompiled header". +This is not standard C++ and will not be added to the stock LodePNG. You can +disable it for lodepng.cpp only by right clicking it, Properties, C/C++, +Precompiled Headers, and set it to Not Using Precompiled Headers there. + +NOTE: Modern versions of VS should be fully supported, but old versions, e.g. +VS6, are not guaranteed to work. + +*) Compilers on Macintosh + +LodePNG has been reported to work both with gcc and LLVM for Macintosh, both for +C and C++. + +*) Other Compilers + +If you encounter problems on any compilers, feel free to let me know and I may +try to fix it if the compiler is modern and standards compliant. + + +10. examples +------------ + +This decoder example shows the most basic usage of LodePNG. More complex +examples can be found on the LodePNG website. + +10.1. decoder C++ example +------------------------- + +#include "lodepng.h" +#include + +int main(int argc, char *argv[]) { + const char* filename = argc > 1 ? argv[1] : "test.png"; + + //load and decode + std::vector image; + unsigned width, height; + unsigned error = lodepng::decode(image, width, height, filename); + + //if there's an error, display it + if(error) std::cout << "decoder error " << error << ": " << lodepng_error_text(error) << std::endl; + + //the pixels are now in the vector "image", 4 bytes per pixel, ordered RGBARGBA..., use it as texture, draw it, ... +} + +10.2. decoder C example +----------------------- + +#include "lodepng.h" + +int main(int argc, char *argv[]) { + unsigned error; + unsigned char* image; + size_t width, height; + const char* filename = argc > 1 ? argv[1] : "test.png"; + + error = lodepng_decode32_file(&image, &width, &height, filename); + + if(error) printf("decoder error %u: %s\n", error, lodepng_error_text(error)); + + / * use image here * / + + free(image); + return 0; +} + +11. state settings reference +---------------------------- + +A quick reference of some settings to set on the LodePNGState + +For decoding: + +state.decoder.zlibsettings.ignore_adler32: ignore ADLER32 checksums +state.decoder.zlibsettings.custom_...: use custom inflate function +state.decoder.ignore_crc: ignore CRC checksums +state.decoder.ignore_critical: ignore unknown critical chunks +state.decoder.ignore_end: ignore missing IEND chunk. May fail if this corruption causes other errors +state.decoder.color_convert: convert internal PNG color to chosen one +state.decoder.read_text_chunks: whether to read in text metadata chunks +state.decoder.remember_unknown_chunks: whether to read in unknown chunks +state.info_raw.colortype: desired color type for decoded image +state.info_raw.bitdepth: desired bit depth for decoded image +state.info_raw....: more color settings, see struct LodePNGColorMode +state.info_png....: no settings for decoder but ouput, see struct LodePNGInfo + +For encoding: + +state.encoder.zlibsettings.btype: disable compression by setting it to 0 +state.encoder.zlibsettings.use_lz77: use LZ77 in compression +state.encoder.zlibsettings.windowsize: tweak LZ77 windowsize +state.encoder.zlibsettings.minmatch: tweak min LZ77 length to match +state.encoder.zlibsettings.nicematch: tweak LZ77 match where to stop searching +state.encoder.zlibsettings.lazymatching: try one more LZ77 matching +state.encoder.zlibsettings.custom_...: use custom deflate function +state.encoder.auto_convert: choose optimal PNG color type, if 0 uses info_png +state.encoder.filter_palette_zero: PNG filter strategy for palette +state.encoder.filter_strategy: PNG filter strategy to encode with +state.encoder.force_palette: add palette even if not encoding to one +state.encoder.add_id: add LodePNG identifier and version as a text chunk +state.encoder.text_compression: use compressed text chunks for metadata +state.info_raw.colortype: color type of raw input image you provide +state.info_raw.bitdepth: bit depth of raw input image you provide +state.info_raw: more color settings, see struct LodePNGColorMode +state.info_png.color.colortype: desired color type if auto_convert is false +state.info_png.color.bitdepth: desired bit depth if auto_convert is false +state.info_png.color....: more color settings, see struct LodePNGColorMode +state.info_png....: more PNG related settings, see struct LodePNGInfo + + +12. changes +----------- + +The version number of LodePNG is the date of the change given in the format +yyyymmdd. + +Some changes aren't backwards compatible. Those are indicated with a (!) +symbol. + +Not all changes are listed here, the commit history in github lists more: +https://github.com/lvandeve/lodepng + +*) 06 mar 2020: simplified some of the dynamic memory allocations. +*) 12 jan 2020: (!) added 'end' argument to lodepng_chunk_next to allow correct + overflow checks. +*) 14 aug 2019: around 25% faster decoding thanks to huffman lookup tables. +*) 15 jun 2019: (!) auto_choose_color API changed (for bugfix: don't use palette + if gray ICC profile) and non-ICC LodePNGColorProfile renamed to + LodePNGColorStats. +*) 30 dec 2018: code style changes only: removed newlines before opening braces. +*) 10 sep 2018: added way to inspect metadata chunks without full decoding. +*) 19 aug 2018: (!) fixed color mode bKGD is encoded with and made it use + palette index in case of palette. +*) 10 aug 2018: (!) added support for gAMA, cHRM, sRGB and iCCP chunks. This + change is backwards compatible unless you relied on unknown_chunks for those. +*) 11 jun 2018: less restrictive check for pixel size integer overflow +*) 14 jan 2018: allow optionally ignoring a few more recoverable errors +*) 17 sep 2017: fix memory leak for some encoder input error cases +*) 27 nov 2016: grey+alpha auto color model detection bugfix +*) 18 apr 2016: Changed qsort to custom stable sort (for platforms w/o qsort). +*) 09 apr 2016: Fixed colorkey usage detection, and better file loading (within + the limits of pure C90). +*) 08 dec 2015: Made load_file function return error if file can't be opened. +*) 24 okt 2015: Bugfix with decoding to palette output. +*) 18 apr 2015: Boundary PM instead of just package-merge for faster encoding. +*) 24 aug 2014: Moved to github +*) 23 aug 2014: Reduced needless memory usage of decoder. +*) 28 jun 2014: Removed fix_png setting, always support palette OOB for + simplicity. Made ColorProfile public. +*) 09 jun 2014: Faster encoder by fixing hash bug and more zeros optimization. +*) 22 dec 2013: Power of two windowsize required for optimization. +*) 15 apr 2013: Fixed bug with LAC_ALPHA and color key. +*) 25 mar 2013: Added an optional feature to ignore some PNG errors (fix_png). +*) 11 mar 2013: (!) Bugfix with custom free. Changed from "my" to "lodepng_" + prefix for the custom allocators and made it possible with a new #define to + use custom ones in your project without needing to change lodepng's code. +*) 28 jan 2013: Bugfix with color key. +*) 27 okt 2012: Tweaks in text chunk keyword length error handling. +*) 8 okt 2012: (!) Added new filter strategy (entropy) and new auto color mode. + (no palette). Better deflate tree encoding. New compression tweak settings. + Faster color conversions while decoding. Some internal cleanups. +*) 23 sep 2012: Reduced warnings in Visual Studio a little bit. +*) 1 sep 2012: (!) Removed #define's for giving custom (de)compression functions + and made it work with function pointers instead. +*) 23 jun 2012: Added more filter strategies. Made it easier to use custom alloc + and free functions and toggle #defines from compiler flags. Small fixes. +*) 6 may 2012: (!) Made plugging in custom zlib/deflate functions more flexible. +*) 22 apr 2012: (!) Made interface more consistent, renaming a lot. Removed + redundant C++ codec classes. Reduced amount of structs. Everything changed, + but it is cleaner now imho and functionality remains the same. Also fixed + several bugs and shrunk the implementation code. Made new samples. +*) 6 nov 2011: (!) By default, the encoder now automatically chooses the best + PNG color model and bit depth, based on the amount and type of colors of the + raw image. For this, autoLeaveOutAlphaChannel replaced by auto_choose_color. +*) 9 okt 2011: simpler hash chain implementation for the encoder. +*) 8 sep 2011: lz77 encoder lazy matching instead of greedy matching. +*) 23 aug 2011: tweaked the zlib compression parameters after benchmarking. + A bug with the PNG filtertype heuristic was fixed, so that it chooses much + better ones (it's quite significant). A setting to do an experimental, slow, + brute force search for PNG filter types is added. +*) 17 aug 2011: (!) changed some C zlib related function names. +*) 16 aug 2011: made the code less wide (max 120 characters per line). +*) 17 apr 2011: code cleanup. Bugfixes. Convert low to 16-bit per sample colors. +*) 21 feb 2011: fixed compiling for C90. Fixed compiling with sections disabled. +*) 11 dec 2010: encoding is made faster, based on suggestion by Peter Eastman + to optimize long sequences of zeros. +*) 13 nov 2010: added LodePNG_InfoColor_hasPaletteAlpha and + LodePNG_InfoColor_canHaveAlpha functions for convenience. +*) 7 nov 2010: added LodePNG_error_text function to get error code description. +*) 30 okt 2010: made decoding slightly faster +*) 26 okt 2010: (!) changed some C function and struct names (more consistent). + Reorganized the documentation and the declaration order in the header. +*) 08 aug 2010: only changed some comments and external samples. +*) 05 jul 2010: fixed bug thanks to warnings in the new gcc version. +*) 14 mar 2010: fixed bug where too much memory was allocated for char buffers. +*) 02 sep 2008: fixed bug where it could create empty tree that linux apps could + read by ignoring the problem but windows apps couldn't. +*) 06 jun 2008: added more error checks for out of memory cases. +*) 26 apr 2008: added a few more checks here and there to ensure more safety. +*) 06 mar 2008: crash with encoding of strings fixed +*) 02 feb 2008: support for international text chunks added (iTXt) +*) 23 jan 2008: small cleanups, and #defines to divide code in sections +*) 20 jan 2008: support for unknown chunks allowing using LodePNG for an editor. +*) 18 jan 2008: support for tIME and pHYs chunks added to encoder and decoder. +*) 17 jan 2008: ability to encode and decode compressed zTXt chunks added + Also various fixes, such as in the deflate and the padding bits code. +*) 13 jan 2008: Added ability to encode Adam7-interlaced images. Improved + filtering code of encoder. +*) 07 jan 2008: (!) changed LodePNG to use ISO C90 instead of C++. A + C++ wrapper around this provides an interface almost identical to before. + Having LodePNG be pure ISO C90 makes it more portable. The C and C++ code + are together in these files but it works both for C and C++ compilers. +*) 29 dec 2007: (!) changed most integer types to unsigned int + other tweaks +*) 30 aug 2007: bug fixed which makes this Borland C++ compatible +*) 09 aug 2007: some VS2005 warnings removed again +*) 21 jul 2007: deflate code placed in new namespace separate from zlib code +*) 08 jun 2007: fixed bug with 2- and 4-bit color, and small interlaced images +*) 04 jun 2007: improved support for Visual Studio 2005: crash with accessing + invalid std::vector element [0] fixed, and level 3 and 4 warnings removed +*) 02 jun 2007: made the encoder add a tag with version by default +*) 27 may 2007: zlib and png code separated (but still in the same file), + simple encoder/decoder functions added for more simple usage cases +*) 19 may 2007: minor fixes, some code cleaning, new error added (error 69), + moved some examples from here to lodepng_examples.cpp +*) 12 may 2007: palette decoding bug fixed +*) 24 apr 2007: changed the license from BSD to the zlib license +*) 11 mar 2007: very simple addition: ability to encode bKGD chunks. +*) 04 mar 2007: (!) tEXt chunk related fixes, and support for encoding + palettized PNG images. Plus little interface change with palette and texts. +*) 03 mar 2007: Made it encode dynamic Huffman shorter with repeat codes. + Fixed a bug where the end code of a block had length 0 in the Huffman tree. +*) 26 feb 2007: Huffman compression with dynamic trees (BTYPE 2) now implemented + and supported by the encoder, resulting in smaller PNGs at the output. +*) 27 jan 2007: Made the Adler-32 test faster so that a timewaste is gone. +*) 24 jan 2007: gave encoder an error interface. Added color conversion from any + greyscale type to 8-bit greyscale with or without alpha. +*) 21 jan 2007: (!) Totally changed the interface. It allows more color types + to convert to and is more uniform. See the manual for how it works now. +*) 07 jan 2007: Some cleanup & fixes, and a few changes over the last days: + encode/decode custom tEXt chunks, separate classes for zlib & deflate, and + at last made the decoder give errors for incorrect Adler32 or Crc. +*) 01 jan 2007: Fixed bug with encoding PNGs with less than 8 bits per channel. +*) 29 dec 2006: Added support for encoding images without alpha channel, and + cleaned out code as well as making certain parts faster. +*) 28 dec 2006: Added "Settings" to the encoder. +*) 26 dec 2006: The encoder now does LZ77 encoding and produces much smaller files now. + Removed some code duplication in the decoder. Fixed little bug in an example. +*) 09 dec 2006: (!) Placed output parameters of public functions as first parameter. + Fixed a bug of the decoder with 16-bit per color. +*) 15 okt 2006: Changed documentation structure +*) 09 okt 2006: Encoder class added. It encodes a valid PNG image from the + given image buffer, however for now it's not compressed. +*) 08 sep 2006: (!) Changed to interface with a Decoder class +*) 30 jul 2006: (!) LodePNG_InfoPng , width and height are now retrieved in different + way. Renamed decodePNG to decodePNGGeneric. +*) 29 jul 2006: (!) Changed the interface: image info is now returned as a + struct of type LodePNG::LodePNG_Info, instead of a vector, which was a bit clumsy. +*) 28 jul 2006: Cleaned the code and added new error checks. + Corrected terminology "deflate" into "inflate". +*) 23 jun 2006: Added SDL example in the documentation in the header, this + example allows easy debugging by displaying the PNG and its transparency. +*) 22 jun 2006: (!) Changed way to obtain error value. Added + loadFile function for convenience. Made decodePNG32 faster. +*) 21 jun 2006: (!) Changed type of info vector to unsigned. + Changed position of palette in info vector. Fixed an important bug that + happened on PNGs with an uncompressed block. +*) 16 jun 2006: Internally changed unsigned into unsigned where + needed, and performed some optimizations. +*) 07 jun 2006: (!) Renamed functions to decodePNG and placed them + in LodePNG namespace. Changed the order of the parameters. Rewrote the + documentation in the header. Renamed files to lodepng.cpp and lodepng.h +*) 22 apr 2006: Optimized and improved some code +*) 07 sep 2005: (!) Changed to std::vector interface +*) 12 aug 2005: Initial release (C++, decoder only) + + +13. contact information +----------------------- + +Feel free to contact me with suggestions, problems, comments, ... concerning +LodePNG. If you encounter a PNG image that doesn't work properly with this +decoder, feel free to send it and I'll use it to find and fix the problem. + +My email address is (puzzle the account and domain together with an @ symbol): +Domain: gmail dot com. +Account: lode dot vandevenne. + + +Copyright (c) 2005-2020 Lode Vandevenne +*/ diff --git a/app/src/main/cpp/core/mops.c b/app/src/main/cpp/core/mops.c index 9835e38..9f5db8b 100644 --- a/app/src/main/cpp/core/mops.c +++ b/app/src/main/cpp/core/mops.c @@ -9,7 +9,7 @@ #include "pch.h" #include "Emu48.h" #include "ops.h" -#include "Opcodes.h" +#include "opcodes.h" #include "io.h" #include "i28f160.h" // flash support @@ -1307,6 +1307,7 @@ VOID WriteIO(BYTE *a, DWORD d, DWORD s) BOOL bDISPADDR = FALSE; // flag addr 0x120-0x124 changed BOOL bLINEOFFS = FALSE; // flag addr 0x125-0x127 changed BOOL bMENUADDR = FALSE; // flag addr 0x130-0x134 changed + DWORD dwAnnunciator = 0; // no annunciator write #if defined DEBUG_IO { @@ -1412,7 +1413,8 @@ VOID WriteIO(BYTE *a, DWORD d, DWORD s) if (c & RST) { CpuReset(); // emulate NRES signal - disp |= (DISP_POINTER | DISP_MAIN | DISP_MENUE | DISP_ANNUN); + disp |= (DISP_POINTER | DISP_MAIN | DISP_MENUE); + dwAnnunciator = 0x3F; // update all annunciators bInterrupt = TRUE; // SHUTDN } break; @@ -1425,11 +1427,9 @@ VOID WriteIO(BYTE *a, DWORD d, DWORD s) // 0010B @ Annunciator control [LA4 LA3 LA2 LA1] = [ alarm alpha -> <- ] case 0x0B: case 0x0C: - if (c!=Chipset.IORam[d]) - { - Chipset.IORam[d] = c; - disp |= DISP_ANNUN; - } + // annunciator changed + dwAnnunciator |= ((Chipset.IORam[d] ^c) << ((d - 0x0B) * 4)) & 0x3F; + Chipset.IORam[d] = c; break; // 0010D = NS:BAUD @@ -1759,7 +1759,7 @@ VOID WriteIO(BYTE *a, DWORD d, DWORD s) StartTimers(); else StopTimers(); - disp |= DISP_ANNUN; // update annunciators + dwAnnunciator = 0x3F; // update all annunciators break; // 00130 = NS:MENUADDR @@ -1842,10 +1842,9 @@ finish: disp &= ~DISP_POINTER; // display pointer updated UpdateDisplayPointers(); } - if (disp & DISP_ANNUN) + if (dwAnnunciator) { - disp &= ~DISP_ANNUN; // annunciators updated - UpdateAnnunciators(); + UpdateAnnunciators(dwAnnunciator); } return; } diff --git a/app/src/main/cpp/core/opcodes.c b/app/src/main/cpp/core/opcodes.c index 74099d4..81a4ecd 100644 --- a/app/src/main/cpp/core/opcodes.c +++ b/app/src/main/cpp/core/opcodes.c @@ -4,7 +4,7 @@ * This file is part of Emu48 * * Copyright (C) 1995 Sebastien Carlier - * Copyright (C) 1999 Christoph Gie�elink + * Copyright (C) 1999 Christoph Gießelink * */ #include "pch.h" @@ -25,7 +25,7 @@ #pragma intrinsic(memset,memcpy) -#include "ops.h" +#include "Ops.h" // Fields start and length UINT F_s[16] = {0/*P*/,0,2,0,15,3,0,0,0,0,0,0,0,0,0,0}; @@ -2444,7 +2444,7 @@ VOID o_goyes5(LPBYTE I) } //////// EXTENSIONS //////// -VOID o81B1(LPBYTE I) // beep patch +VOID o81B1(LPBYTE I) { if (cCurrentRomType=='Q' || cCurrentRomType=='2' || cCurrentRomType=='P') { @@ -2454,9 +2454,8 @@ VOID o81B1(LPBYTE I) // beep patch } else { - // Emu48 borrows this opcode for the beep patch on the non-ARM-based calculators - External(&w); // beep patch - PCHANGED; // update field select table + // this opcode was used for the beep patch on the non-ARM-based calculators, not used any more + o_invalid4(I); } return; }