Does it really optimize the Huffman trees better? I wouldn't think there's more you can do to optimize Huffman trees than make them reflect the actual histogram

Does it really optimize the Huffman trees better? I wouldn't think there's more you can do to optimize Huffman trees than make them reflect the actual histogram. Mozjpeg does try different progressive scan scripts – different scripts lead to different compression behavior. That helps a bit, though I don't like it when it separates the Cb and Cr planes, becauses that leads to "flash of weird color" when decoding progressively. See also: https://cloudinary.com/blog/progressive_jpegs_and_green_martians https://cloudinary.com/blog/progressive_jpegs_and_green_mart...