hohmiyazawa / hoh-ans Goto Github PK

Experimental lossless image compression, based on rANS entropy coding (ryg-rans) and traditional prediction and colour space transforms.

Proof of concept, useless for most edge cases.

Encoding:

choh infile.rgb outfile.hoh width height -sN

Where "N" is a number 0-4 (fast-slow). "infile.rgb" must consist of raw 8bit RGB bytes. You can make such a file with imagemagick:

convert input.png -depth 8 rgb:infile.rgb

Encoded size is reported, but no data is written. (Work in progress, it currently writes headers and stuff).

Decoding:

dhoh infile.hoh outfile.rgb

make

That's all you should need. Requires GNU make and gcc. Only tested on 64bit x86.