SlackBuildsOrg/multimedia/gimp-gap

GIMP-GAP, the GIMP Animation Package, is a collection of plug-ins
to extend GIMP 2.6 and above with capabilities to edit and create
animations as sequences of single frames.

By default, the script will try to detect all optional requirements.
In case you don't have those requirements, you can disable it by
passing variables to the script (VAR=yes/no ./gimp-gap.SlackBuild):
LAME=yes|no (default: yes), requires lame
FAAC=yes|no (default: yes), requires faac
FAAD=yes|no (default: yes), requires faad2
X264=yes|no (default: yes), requires x264
AVFORMAT=yes|no (default: yes), requires ffmpeg
MPEG=yes|no (default: yes), requires libmpeg
XVID=yes|no (default: yes), requires xvidcore