Here's a worst case test image for chroma subsampling: https://commons.wikimedia.org/wiki/File%3ARicardo_Quaresma_%28L%29%2C_Pablo_Zabaleta_%28R%29_%E2%80%93_P

Here's a worst case test image for chroma subsampling: https://commons.wikimedia.org/wiki/File%3ARicardo_Quaresma_%28L%29%2C_Pablo_Zabaleta_%28R%29_%E2%80%93_Portugal_vs._Argentina%2C_9th_February_2011.jpg https://commons.wikimedia.org/wiki/File%3ARicardo_Quaresma_%... I first saw this in Fabrice Bellard's BPG demonstration at http://xooyoozoo.github.io/yolo-octo-bugfixes/ http://xooyoozoo.github.io/yolo-octo-bugfixes/ ("Soccer Players"). Every lossy format fails to reproduce the red dots on the green stripe because they all use chroma subsampling. Until I see tools that can automatically deal with images like this I think the anti-subsampling attitude mentioned in the article is correct. "Unless you are willing to evaluate each image, the thinking goes, you should avoid subsampling."