2021-04-21, 09:59
(2021-04-21, 08:48)shrugg1e Wrote: Apple advertises 2160p HDR at 60 fps.
Is there a framerate limit on the old ATV 4K? Just 30 fps at HDR?
Apparently yes. BBC iPlayer UHD HDR includes 2160p50 HLG HDR content for live sport - and I believe the lack of support for >30fps at 2160p HDR has been an issue with rolling this out to current ATV 4Ks. (However 2160p50 in SDR is supported I believe - so I'm surprised at this limitation - unless it's to do with tone mapping processing requirements, as replay of SDR and HDR content otherwise is just adding a few bits of metadata to an HDMI info frame - h.265 decoding of 2160p50 SDR and 2160p50 HDR is identical - and the current ATV4K has h.265 acceleration - even for 4:2:2 and 4:4:4 unusually, because of Airplay mirroring requirements for Mac and iPhone/iPads not to colour smear)
I believe tvOS has had HLG support for a while - but it will definitely need it in the new device as iPhone 12 DV material is based around an HLG core stream (not HDR 10 as DV UHD BDs are)
