2 ms·
PNG compresses "exact" gradients pretty well. I'd be interested in a tool that not only reduces colors (what this one is doing), but also smooths gradient-like
by gcr 14y ago
PNG compresses "exact" gradients pretty well. I'd be interested in a tool that not only reduces colors (what this one is doing), but also smooths gradient-like segments of the image to comrpess better.
- dunham 14y agoYeah, I am curious how much you can improve compression by keeping everything 24 bit, but slightly tweaking the color values to make the result more compressible. (PNG applies one of five predictors to each line, takes the difference from the prediction, and deflates the result.) For example, as a greedy algorithm: find the best predictor for a line, then tweak the line to reduce the alphabet (round off the difference from predicted values) or to get longer deflate matches (substitute values if they're close and match a previous run).