> their demo only uses two passes for progressive AVIF -- it's just their choice
Also worth mentioning: AFAIK "their choice" here is just the default, i.e. what `avifenc --progressive` outputs, so maybe if the default is suboptimal, it could be improved?
> Even still, the demo proves that AVIF can deliver a usable image with up to 3x as fewer bytes as JXL!
Usable for what? As a clearly loading image / placeholder, I personally like the JXL version better (as already indicated in my previous comment). As a final image I think both of them are unusable, and if that's the intention I think it would be better to encode both aiming for very low quality, maybe also reducing the resolution, without progressive loading, then compare. My understanding is that AVIF is usually better at very low bitrates, so it would probably be better, but I don't think this example "proves" that.
Also worth mentioning: AFAIK "their choice" here is just the default, i.e. what `avifenc --progressive` outputs, so maybe if the default is suboptimal, it could be improved?
> Even still, the demo proves that AVIF can deliver a usable image with up to 3x as fewer bytes as JXL!
Usable for what? As a clearly loading image / placeholder, I personally like the JXL version better (as already indicated in my previous comment). As a final image I think both of them are unusable, and if that's the intention I think it would be better to encode both aiming for very low quality, maybe also reducing the resolution, without progressive loading, then compare. My understanding is that AVIF is usually better at very low bitrates, so it would probably be better, but I don't think this example "proves" that.