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0 pointsPaulHoule2y ago0 comments

It's a Jedi mind trick.

The compression artifacts in the self-shadows of the red bit of the car to the left of the driver's head look awful to me. It's true that the compression artifact blends in pretty well and you might think the car really looks like that but personally I can't unsee things like that once I look at them in comparison.

The thing is that it is that play of reflections and shadows that makes an expensive sports car look so sexy.

0 comments

CharlesW2y ago

> It's a Jedi mind trick.

All compression is. :^) The additional twist is that our eyes/brains do a great job at glossing over compression artifacts that we're used to.

When you expand the image, you can change the formats on both sides for A/B testing. Comparing "JPEG - 20.7 kB" to "AVIF - 18.2 kB" is an enlightening like-vs-like size comparison.

I'd be happy to do an AVIF encode of a large uncompressed/losslessly compressed image that meets your "near visually lossless" bar. I'm assuming that JPEG must do better in comparison to AVIF at large file sizes, but I can't find good examples of this.

account422y ago

> Comparing "JPEG - 20.7 kB" to "AVIF - 18.2 kB" is an enlightening like-vs-like size comparison.

You can't extrapolate that comparison to higher bitrates though - so unless your use case doesn't require preserving image detail (i.e. the images might as well not be there), both formats are inadequate at that size.

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