PREDICTION-ENCODED PIXELS

Summary from the TLDR newsletter

Prediction-Encoded Pixels is a format specifically designed for low-color pixel art. It uses 'Prediction by Partial Matching, Order-2' compression, which is able to compress packed-palette-indices smaller than GIF, PNG, and QOI. It's two to 10 times slower than GIF/PNG/QOI, depending on the image, but it often compresses images 20% to 50% smaller than GIF/PNG, and multiple times smaller than QOI. The format is still in an experimental phase.