The main idea is to be able to load an image progressively but not line by line as today jpeg. The full image should appear at the start and the quality will increase progressively
This allow to have lossless compression without affecting performances. Actually the user experience is improved since a preview of the image appears immediatly and the final quality is better
---> FLIF does exactly that and does it well : https://github.com/FLIF-hub/FLIF