@nixCraft WebP includes a lossy and lossless algorithm, which are completely different and separate. Why cram both in the same file format? If the use case in practice only requires one or the other type, as most use cases do, half of WebP is unnecessary.
Want to re-implement WebP? You have to implement both algorithms. Way harder, than, say, re-implementing simple but effective PNG that just does one thing well.
I'd rather upgrade to backward-compatible PNGX. https://mooncore.eu/bunny/txt/pngx-eval.htm