Quote from: Fake HDMI 2.1' bandwidth? on July 23, 2023, 12:28:54For full 120Hz 10bit HDR 444chroma 32.27 Gbit/s are required.
((3840+80)*(2160+127)*3*10*(1)*120)/10^9 -> 32.27 Gbit/s.
HDMI 2.1 FRL4 (32G) can only do 104.7 Hz in this case.
HDMI 2.1 FRL5 (40G) can do 129.3 Hz, so would be enough in this case.
HDMI 2.1 uses DSC lossy compression for transmission modes exceed the maximum bitrate for the transmitter/receiver.
HDMI 2.1 uses DSC lossy compression for transmission modes at the maximum bit rate for the transmitter/receiver.
In theory, if there is a smart scheme, it should remove service traffic and even 144Hz / 30 bit 444 should pass almost without compression, because. for this mode, you need 35.871Gbps, i.e. it lacks quite a bit when compressed with DSC and even 40Gbps (and you are always talking about the bandwidth with service traffic by encoding 16/18, not pure user data).
40Gbps x (16/18) gives ~35.55Gbps of pure data.
Additional synchronization data can be added by DSC compressor (and unpack/restore) at the end at the HDMI chip logic level according to any CVT(-RB)/GTF/DMT video modes scheme. This is exactly what I would do with lossless compression or packaging - why transfer data outside the frame for synchronization, if all modes are standard and all that is required is only data with a control flag with what delay and how to draw?