leocad/common/quant.cpp
2011-09-07 21:06:51 +00:00

640 lines
15 KiB
C++

///////////////////////////////////////
// DL1 Quantization
#include <stdlib.h>
#include <math.h>
#include <memory.h>
#include <string.h>
#include "quant.h"
//#define FAST // improves speed but uses a lot of memory
#define QUAL1 // slightly improves quality
//#define QUAL2 // slightly improves quality
//#define DITHER1 // 1-val error diffusion dither
#define DITHER2 // 2-val error diffusion dither
//#define DITHER4 // 4-val error diffusion dither (Floyd-Steinberg)
#define DITHER_MAX 20
static void dlq_finish();
static int build_table(unsigned char *image, unsigned long pixels);
static void fixheap(unsigned long id);
static void reduce_table(int num_colors);
static void set_palette(int index, int level);
static void closest_color(int index, int level);
static int quantize_image(unsigned char *in, unsigned char *out, int width, int height, int dither);
static int bestcolor(int r, int g, int b);
static unsigned char palette[3][256];
static CUBE *rgb_table[6];
static unsigned short r_offset[256], g_offset[256], b_offset[256];
static CLOSEST_INFO c_info;
static int tot_colors, pal_index;
static unsigned long *squares;
static FCUBE *heap = NULL;
static short *dl_image = NULL;
bool dl1quant(unsigned char *inbuf, unsigned char *outbuf, int width, int height, int quant_to, int dither, unsigned char userpal[3][256])
{
int i;
// dlq_init
for (i = 0; i < 6; i++)
rgb_table[i]=NULL;
tot_colors=0;
pal_index=0;
heap = NULL;
dl_image = NULL;
for (i = 0; i < 256; i++)
{
r_offset[i] = (i & 128) << 7 | (i & 64) << 5 | (i & 32) << 3 |
(i & 16) << 1 | (i & 8) >> 1;
g_offset[i] = (i & 128) << 6 | (i & 64) << 4 | (i & 32) << 2 |
(i & 16) << 0 | (i & 8) >> 2;
b_offset[i] = (i & 128) << 5 | (i & 64) << 3 | (i & 32) << 1 |
(i & 16) >> 1 | (i & 8) >> 3;
}
c_info.palette_index=0;
c_info.red=0;
c_info.green=0;
c_info.blue=0;
c_info.distance=0;
for (i = (-255); i <= 255; i++)
c_info.squares[i+255] = i*i;
for (i = 0; i < 256; i++)
{
palette[0][i] = 0;
palette[1][i] = 0;
palette[2][i] = 0;
}
squares = c_info.squares + 255;
// dlq_start
rgb_table[0] = (CUBE*)calloc(sizeof(CUBE), 1);
rgb_table[1] = (CUBE*)calloc(sizeof(CUBE), 8);
rgb_table[2] = (CUBE*)calloc(sizeof(CUBE), 64);
rgb_table[3] = (CUBE*)calloc(sizeof(CUBE), 512);
rgb_table[4] = (CUBE*)calloc(sizeof(CUBE), 4096);
rgb_table[5] = (CUBE*)calloc(sizeof(CUBE), 32768);
for (i = 0; i <= 5; i++)
if (rgb_table[i] == NULL)
{
dlq_finish();
return false;
}
pal_index = 0;
if (build_table(inbuf, width*height) == 0)
{
dlq_finish();
return false;
}
reduce_table(quant_to);
set_palette(0, 0);
if (quantize_image(inbuf, outbuf, width, height, dither) == 0)
{
dlq_finish();
return false;
}
dlq_finish();
for (i = 0; i < 256; i++)
{
userpal[0][i] = palette[0][i];
userpal[1][i] = palette[1][i];
userpal[2][i] = palette[2][i];
}
return true;
}
static void dlq_finish(void)
{
for (int i = 0;i < 6;i++)
{
if (rgb_table[i] != NULL)
{
free(rgb_table[i]);
rgb_table[i] = NULL;
}
}
if (heap != NULL)
{
free(heap);
heap = NULL;
}
if (dl_image != NULL)
{
free(dl_image);
dl_image = NULL;
}
memset(&c_info, 0, sizeof(CLOSEST_INFO));
tot_colors=pal_index=0;
}
// returns 1 on success, 0 on failure
static int build_table(unsigned char *image, unsigned long pixels)
{
unsigned long i = 0, index = 0, cur_count = 0, head = 0, tail = 0;
long j = 0;
heap = (FCUBE *) malloc(sizeof(FCUBE) * 32769);
if (heap == NULL)
return 0;
#ifdef FAST
dl_image = malloc(sizeof(short) * pixels);
if (dl_image == NULL)
return 0;
#endif
for (i = 0; i < pixels; i++)
{
#ifdef FAST
dl_image[i] = index = r_offset[image[0]] + g_offset[image[1]] + b_offset[image[2]];
#else
index = r_offset[image[0]] + g_offset[image[1]] + b_offset[image[2]];
#endif
#ifdef QUAL1
rgb_table[5][index].r += image[0];
rgb_table[5][index].g += image[1];
rgb_table[5][index].b += image[2];
#endif
rgb_table[5][index].pixel_count++;
image += 3;
}
tot_colors = 0;
for (i = 0; i < 32768; i++)
{
cur_count = rgb_table[5][i].pixel_count;
if (cur_count)
{
heap[++tot_colors].level = 5;
heap[tot_colors].index = (unsigned short)i;
rgb_table[5][i].pixels_in_cube = cur_count;
#ifndef QUAL1
rgb_table[5][i].r = cur_count * (((i & 0x4000) >> 7 |
(i & 0x0800) >> 5 | (i & 0x0100) >> 3 |
(i & 0x0020) >> 1 | (i & 0x0004) << 1) + 4);
rgb_table[5][i].g = cur_count * (((i & 0x2000) >> 6 |
(i & 0x0400) >> 4 | (i & 0x0080) >> 2 |
(i & 0x0010) >> 0 | (i & 0x0002) << 2) + 4);
rgb_table[5][i].b = cur_count * (((i & 0x1000) >> 5 |
(i & 0x0200) >> 3 | (i & 0x0040) >> 1 |
(i & 0x0008) << 1 | (i & 0x0001) << 3) + 4);
#endif
head = i;
for (j = 4; j >= 0; j--)
{
tail = head & 0x7;
head >>= 3;
rgb_table[j][head].pixels_in_cube += cur_count;
rgb_table[j][head].children |= 1 << tail;
}
}
}
for (i = tot_colors; i > 0; i--)
fixheap(i);
return 1;
}
static void fixheap(unsigned long id)
{
unsigned char thres_level = heap[id].level;
unsigned long thres_index = heap[id].index, index = 0;
unsigned long half_totc = tot_colors >> 1;
unsigned long thres_val = rgb_table[thres_level][thres_index].pixels_in_cube;
while (id <= half_totc)
{
index = id << 1;
if (index < (unsigned long)tot_colors)
if (rgb_table[heap[index].level][heap[index].index].pixels_in_cube
> rgb_table[heap[index+1].level][heap[index+1].index].pixels_in_cube)
index++;
if (thres_val <= rgb_table[heap[index].level][heap[index].index].pixels_in_cube)
break;
else {
heap[id] = heap[index];
id = index;
}
}
heap[id].level = thres_level;
heap[id].index = (unsigned short)thres_index;
}
static void reduce_table(int num_colors)
{
while (tot_colors > num_colors)
{
unsigned char tmp_level = heap[1].level, t_level = (tmp_level - 1) > 0 ? (tmp_level - 1) : 0;
unsigned long tmp_index = heap[1].index, t_index = tmp_index >> 3;
if (rgb_table[t_level][t_index].pixel_count)
heap[1] = heap[tot_colors--];
else
{
heap[1].level = t_level;
heap[1].index = (unsigned short)t_index;
}
rgb_table[t_level][t_index].pixel_count += rgb_table[tmp_level][tmp_index].pixel_count;
rgb_table[t_level][t_index].r += rgb_table[tmp_level][tmp_index].r;
rgb_table[t_level][t_index].g += rgb_table[tmp_level][tmp_index].g;
rgb_table[t_level][t_index].b += rgb_table[tmp_level][tmp_index].b;
rgb_table[t_level][t_index].children &= ~(1 << (tmp_index & 0x7));
fixheap(1);
}
}
static void set_palette(int index, int level)
{
int i;
if (rgb_table[level][index].children)
for (i = 7; i >= 0; i--)
if (rgb_table[level][index].children & (1 << i))
set_palette((index << 3) + i, level + 1);
if (rgb_table[level][index].pixel_count)
{
unsigned long r_sum, g_sum, b_sum, sum;
rgb_table[level][index].palette_index = pal_index;
r_sum = rgb_table[level][index].r;
g_sum = rgb_table[level][index].g;
b_sum = rgb_table[level][index].b;
sum = rgb_table[level][index].pixel_count;
palette[0][pal_index] = (unsigned char)((r_sum + (sum >> 1)) / sum);
palette[1][pal_index] = (unsigned char)((g_sum + (sum >> 1)) / sum);
palette[2][pal_index] = (unsigned char)((b_sum + (sum >> 1)) / sum);
pal_index++;
}
}
static void closest_color(int index, int level)
{
int i;
if (rgb_table[level][index].children)
for (i = 7; i >= 0; i--)
if (rgb_table[level][index].children & (1 << i))
closest_color((index << 3) + i, level + 1);
if (rgb_table[level][index].pixel_count)
{
long dist, r_dist, g_dist, b_dist;
unsigned char pal_num = rgb_table[level][index].palette_index;
// Determine if this color is "closest".
r_dist = palette[0][pal_num] - c_info.red;
g_dist = palette[1][pal_num] - c_info.green;
b_dist = palette[2][pal_num] - c_info.blue;
dist = squares[r_dist] + squares[g_dist] + squares[b_dist];
if (dist < (long)c_info.distance)
{
c_info.distance = dist;
c_info.palette_index = pal_num;
}
}
}
// returns 1 on success, 0 on failure
static int quantize_image(unsigned char *in, unsigned char *out, int width, int height, int dither)
{
if (!dither)
{
unsigned long i = 0, pixels = width * height;
unsigned short level = 0, index = 0;
unsigned char tmp_r = 0, tmp_g = 0, tmp_b = 0, cube = 0;
unsigned char *lookup = NULL;
lookup = (unsigned char*)malloc(sizeof(char) * 32768);
if (lookup == NULL)
return 0;
for (i = 0; i < 32768; i++)
if (rgb_table[5][i].pixel_count)
{
tmp_r = (unsigned char)((i & 0x4000) >> 7 | (i & 0x0800) >> 5 |
(i & 0x0100) >> 3 | (i & 0x0020) >> 1 |
(i & 0x0004) << 1);
tmp_g = (unsigned char)((i & 0x2000) >> 6 | (i & 0x0400) >> 4 |
(i & 0x0080) >> 2 | (i & 0x0010) >> 0 |
(i & 0x0002) << 2);
tmp_b = (unsigned char)((i & 0x1000) >> 5 | (i & 0x0200) >> 3 |
(i & 0x0040) >> 1 | (i & 0x0008) << 1 |
(i & 0x0001) << 3);
#ifdef QUAL2
lookup[i] = bestcolor(tmp_r, tmp_g, tmp_b);
#else
c_info.red = tmp_r + 4;
c_info.green = tmp_g + 4;
c_info.blue = tmp_b + 4;
level = 0;
index = 0;
for (;;) {
cube = (tmp_r&128) >> 5 | (tmp_g&128) >> 6 | (tmp_b&128) >> 7;
if ((rgb_table[level][index].children & (1 << cube)) == 0) {
c_info.distance = (unsigned long)~0L;
closest_color(index, level);
lookup[i] = c_info.palette_index;
break;
}
level++;
index = (index << 3) + cube;
tmp_r <<= 1;
tmp_g <<= 1;
tmp_b <<= 1;
}
#endif
}
for (i = 0; i < pixels; i++)
{
#ifdef FAST
out[i] = lookup[dl_image[i]];
#else
out[i] = lookup[r_offset[in[0]] + g_offset[in[1]] + b_offset[in[2]]];
in += 3;
#endif
}
free(lookup);
}
else // dither
{
#if defined(DITHER2) || defined(DITHER4)
long i = 0, j = 0;
long r_pix = 0, g_pix = 0, b_pix = 0;
long offset = 0, dir = 0;
long odd_scanline = 0;
long err_len = (width + 2) * 3;
unsigned char *range_tbl = NULL, *range = NULL;
short *lookup = NULL, *erowerr = NULL, *orowerr = NULL;
short *thisrowerr = NULL, *nextrowerr = NULL;
char *dith_max_tbl = NULL, *dith_max = NULL;
lookup = (short*)malloc(sizeof(short) * 32768);
erowerr = (short*)malloc(sizeof(short) * err_len);
orowerr = (short*)malloc(sizeof(short) * err_len);
range_tbl = (unsigned char*)malloc(3 * 256);
range = range_tbl + 256;
dith_max_tbl= (char*)malloc(512);
dith_max = dith_max_tbl + 256;
if (range_tbl == NULL || lookup == NULL || erowerr == NULL || orowerr == NULL || dith_max_tbl == NULL)
{
if (range_tbl != NULL)
{
free(range_tbl);
range_tbl=NULL;
}
if (lookup != NULL)
{
free(lookup);
lookup=NULL;
}
if (erowerr != NULL)
{
free(erowerr);
erowerr=NULL;
}
if (orowerr != NULL)
{
free(orowerr);
orowerr=NULL;
}
if (dith_max_tbl != NULL)
{
free(dith_max_tbl);
dith_max_tbl=NULL;
}
return 0;
}
for (i = 0; i < err_len; i++)
erowerr[i] = 0;
for (i = 0; i < 32768; i++)
lookup[i] = -1;
for (i = 0; i < 256; i++)
{
range_tbl[i] = 0;
range_tbl[i + 256] = (unsigned char) i;
range_tbl[i + 512] = 255;
}
for (i = 0; i < 256; i++)
{
dith_max_tbl[i] = -DITHER_MAX;
dith_max_tbl[i + 256] = DITHER_MAX;
}
for (i = -DITHER_MAX; i <= DITHER_MAX; i++)
dith_max_tbl[i + 256] = (char)i;
for (i = 0 ; i < height; i++)
{
if (odd_scanline)
{
dir = -1;
in += (width - 1) * 3;
out += (width - 1);
thisrowerr = orowerr + 3;
nextrowerr = erowerr + width * 3;
}
else
{
dir = 1;
thisrowerr = erowerr + 3;
nextrowerr = orowerr + width * 3;
}
nextrowerr[0] = nextrowerr[1] = nextrowerr[2] = 0;
for (j = 0; j < width; j++)
{
#ifdef DITHER2
r_pix = range[(thisrowerr[0] >> 1) + in[0]];
g_pix = range[(thisrowerr[1] >> 1) + in[1]];
b_pix = range[(thisrowerr[2] >> 1) + in[2]];
#else
r_pix = range[((thisrowerr[0] + 8) >> 4) + in[0]];
g_pix = range[((thisrowerr[1] + 8) >> 4) + in[1]];
b_pix = range[((thisrowerr[2] + 8) >> 4) + in[2]];
#endif
offset = (r_pix&248) << 7 | (g_pix&248) << 2 | b_pix >> 3;
if (lookup[offset] < 0)
lookup[offset] = bestcolor(r_pix, g_pix, b_pix);
*out = (unsigned char)lookup[offset];
r_pix = dith_max[r_pix - palette[0][lookup[offset]]];
g_pix = dith_max[g_pix - palette[1][lookup[offset]]];
b_pix = dith_max[b_pix - palette[2][lookup[offset]]];
#ifdef DITHER2
nextrowerr[0 ] = (short)r_pix;
thisrowerr[0+3] += (short)r_pix;
nextrowerr[1 ] = (short)g_pix;
thisrowerr[1+3] += (short)g_pix;
nextrowerr[2 ] = (short)b_pix;
thisrowerr[2+3] += (short)b_pix;
#else
two_val = r_pix * 2;
nextrowerr[0-3] = r_pix;
r_pix += two_val;
nextrowerr[0+3] += r_pix;
r_pix += two_val;
nextrowerr[0 ] += r_pix;
r_pix += two_val;
thisrowerr[0+3] += r_pix;
two_val = g_pix * 2;
nextrowerr[1-3] = g_pix;
g_pix += two_val;
nextrowerr[1+3] += g_pix;
g_pix += two_val;
nextrowerr[1 ] += g_pix;
g_pix += two_val;
thisrowerr[1+3] += g_pix;
two_val = b_pix * 2;
nextrowerr[2-3] = b_pix;
b_pix += two_val;
nextrowerr[2+3] += b_pix;
b_pix += two_val;
nextrowerr[2 ] += b_pix;
b_pix += two_val;
thisrowerr[2+3] += b_pix;
#endif
thisrowerr += 3;
nextrowerr -= 3;
in += dir * 3;
out += dir;
}
if ((i % 2) == 1)
{
in += (width + 1) * 3;
out += (width + 1);
}
odd_scanline = !odd_scanline;
}
free(range_tbl);
free(lookup);
free(erowerr);
free(orowerr);
free(dith_max_tbl);
#else
long i = 0, j = 0;
long r_pix = 0, g_pix = 0, b_pix=0;
long r_err = 0, g_err = 0, b_err=0;
long offset = 0;
BYTE *range_tbl = (BYTE*)malloc(3 * 256), *range = range_tbl + 256;
short *lookup = (sshort *)malloc(sizeof(short) * 32768);
if (range_tbl == NULL || lookup == NULL)
{
if (range_tbl != NULL)
free(range_tbl);
if (lookup != NULL)
free(lookup);
return 0;
}
for (i = 0; i < 32768; i++)
lookup[i] = -1;
for (i = 0; i < 256; i++)
{
range_tbl[i] = 0;
range_tbl[i + 256] = (BYTE) i;
range_tbl[i + 512] = 255;
}
for (i = 0; i < height; i++)
{
r_err = g_err = b_err = 0;
for (j = width - 1; j >= 0; j--)
{
r_pix = range[(r_err >> 1) + in[0]];
g_pix = range[(g_err >> 1) + in[1]];
b_pix = range[(b_err >> 1) + in[2]];
offset = (r_pix&248) << 7 | (g_pix&248) << 2 | b_pix >> 3;
if (lookup[offset] < 0)
lookup[offset] = bestcolor(r_pix, g_pix, b_pix);
*out++ = (unsigned char)lookup[offset];
r_err = r_pix - palette[0][lookup[offset]];
g_err = g_pix - palette[1][lookup[offset]];
b_err = b_pix - palette[2][lookup[offset]];
in += 3;
}
}
free(range_tbl);
free(lookup);
#endif
}
return 1;
}
static int bestcolor(int r, int g, int b)
{
unsigned long i = 0, bestcolor = 0, curdist = 0, mindist = 0;
long rdist = 0, gdist = 0, bdist = 0;
r = (r & 248) + 4;
g = (g & 248) + 4;
b = (b & 248) + 4;
mindist = 200000;
for (i = 0; i < (unsigned long)tot_colors; i++)
{
rdist = palette[0][i] - r;
gdist = palette[1][i] - g;
bdist = palette[2][i] - b;
curdist = squares[rdist] + squares[gdist] + squares[bdist];
if (curdist < mindist)
{
mindist = curdist;
bestcolor = i;
}
}
return bestcolor;
}