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0 pointsmikeash11y ago0 comments

Just a nitpick, JPEG always encodes the color channels at half resolution. It's amazing how difficult it is to notice this, though.

0 comments

No, there are 4:4:4 and 4:2:2 modes in JPEG.

H.264 also defines such modes, but no consumer hardware decoders support them so they aren't commonly used.

mikeashOP11y ago

My mistake, I must have been going off what's common versus what's allowed. Thanks for pointing it out.

dunham11y ago

Apple's jpeg animation hack used 4:4:4 so the blocks wouldn't interfere with each other. It's a neat hack, worth reading about if you haven't seen it yet: https://docs.google.com/document/pub?id=1GWTMLjqQsQS45FWwqNG...

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0 pointsmikeash11y ago0 comments

Just a nitpick, JPEG always encodes the color channels at half resolution. It's amazing how difficult it is to notice this, though.

No, there are 4:4:4 and 4:2:2 modes in JPEG.

H.264 also defines such modes, but no consumer hardware decoders support them so they aren't commonly used.

mikeashOP11y ago

My mistake, I must have been going off what's common versus what's allowed. Thanks for pointing it out.

dunham11y ago

j / k navigate · click thread line to collapse