It's been a thing for at least 20 years, when "wavelet" compression first started being used. https://en.wikipedia.org/wiki/JPEG_2000#Progressive_transmission_

It's been a thing for at least 20 years, when "wavelet" compression first started being used. https://en.wikipedia.org/wiki/JPEG_2000#Progressive_transmission_by_pixel_and_resolution_accuracy https://en.wikipedia.org/wiki/JPEG_2000#Progressive_transmis... And the Digital Cinema formats widely used today rely on this so a 2K or 4K stream can be extracted from the same file. What's "new" about FLIF is the better lossless compression rate