Playing with lossless image compression based on the quadtree data structure

Quick start:

Encode smpte.ppm PNM picture file to encoded.lqt:

./encode smpte.ppm encoded.lqt

Decode encoded.lqt file to decoded.ppm picture file:

./decode encoded.lqt decoded.ppm

Watch decoded.ppm picture file in feh:

feh decoded.ppm

Disable color space transformation:

Use the sRGB color space directly instead of the default 1 Reversible Color Transform:

./encode smpte.ppm encoded.lqt 0

Limited storage capacity

Use up to 65536 bits of space instead of the default 0 (no limit) and discard quality bits, if necessary, to stay below 65536 bits:

./encode smpte.ppm encoded.lqt 1 65536