QOIR: A fast, simple, lossless image file format

Re:QOIR: A fast, simple, lossless image file format by kevmo314 on Tuesday December 06, 2022 @10:15PM (#33890239)

> For example, if you have a relatively wimpy camera that streams out a 160×120 grayscale image, it might be fun to see how far you can push something like combining:

I'm typically not one for self-promo but I did this with video and you can get 90% compression with exactly those three basic steps. RGB -> YUV420, delta encoding, then basically-upgraded-RLE. You can find the guide here: https://github.com/kevmo314/codec-from-scratch

[ Parent | on HN ]

Re:QOIR: A fast, simple, lossless image file format by vanderZwan on Wednesday December 07, 2022 @06:22AM (#33893131)

Nice! The caveat being that this assumes we have little to no shot noise I guess? Since that is where lossy codecs typically beat lossless.

[ Parent | on HN ]

Re:QOIR: A fast, simple, lossless image file format by kevmo314 on Wednesday December 07, 2022 @09:54AM (#33894969)

Yep adding noise would mess up the deltas which would reduce the efficiency. This can be mitigated with a quantizer, which I was hoping to write about next.

I suspect it's possible to achieve 99% lossy compression without getting too complex to be understandable in the toy codec with a couple more of these similar techniques.

[ Parent | on HN ]

Re:QOIR: A fast, simple, lossless image file format by graderjs on Wednesday December 07, 2022 @06:18AM (#33893098)

Thanks! I just forked it. Do you know if Apache-2.0 code can be included into a closed source project?

[ Parent | on HN ]

Re:QOIR: A fast, simple, lossless image file format by askiiart on Wednesday December 07, 2022 @03:18PM (#33899670)

[choosealicense](https://choosealicense.com/licenses/apache-2.0/)

[ Parent | on HN ]