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[benwaggoner]

Originally Posted by excellentswordfight

Maybe more fitting for the AV1 section. Either way, my first thought was that isnt it a bit odd using AV1 for uhd given the fact that doesnt support HDR. Like how many TVs has av1 support and not HDR-support? I assume that the HDR stream will be preferred if the tv-set support it. I dont know how it is in other regions, but were I live its pretty much only netflix premium content that offer UHD, and that content almost always has an hdr stream. So how many will actually stream the AV1 top stream?

AV1 supports HDR in the sense the spec supports the signaling and it supports 10-bit encoding. However HDR's PQ has some different psychovisual properties than SDR's good old gamma, and requires different tuning.

Anecdotally, AV1 encoders seem to have been struggling with this more than makes sense. Perhaps overengineering around SDR's perceptual nonlinearity? I don't see any fundamental spec-level reason why AV1 should struggle with HDR.