Playing with lossy image compression based on the singular value decomposition

Quick start:

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

./encode smpte.ppm encoded.svd

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

./decode encoded.svd decoded.ppm

Watch decoded.ppm picture file in feh:

feh decoded.ppm

Adjusting quantization

Use quantization values of seven for luminance (Y’), six and seven for chrominance (Cb and Cr) instead of the default 12 10 10 values:

./encode smpte.ppm encoded.svd 7 6 5

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.svd 12 10 10 65536

Reading

Singular value decomposition