Originally Posted by mpgxsvcd
I can set my 3 year old 1080p Blu-ray player to output upscaled 10 bit 4K/UHD over HDMI 1.4. That player was made at least a year before HDMI 2.0 was finalized and yet it can still do it.
Also my Nvidia 870m can output 10 bit 4K/UHD @ 60 FPS 4:2:0 and that card came out 1 year before HDMI 2.0.
In addition the HDMI wiki page says nothing about 10 bit ever being added for HDMI 2.0. In fact it doesn't indicate that it was ever added.
I believe that higher bit depths have been supported since HDMI 1.3 or else deep color wouldn't have worked when it was added for HDMI 1.3. However, I am willing to hear any arguments against this. Please provide a reference stating that 10 bit was not supported until HDMI 2.0.
According to the HDMI 2.0 FAQ on HDMI.org's website, there was no "official" support for 10-bit 2160p in HDMI 1.4. However, the HDMI 1.4 spec did officially support 12-bit 2160p with 4:2:2 chroma subsampling at up to 30fps. HDMI 2.0 added support for 10, 12, & 16-bit 2160p with RGB/4:4:4 at up to 30 fps. It also added support for 8, 10, 12, & 16-bit 2160p with 4:2:0 chroma at 50/60 fps, 8-bit 2160p with RGB/4:4:4 at 50/60 fps, and 12-bit 2160p with 4:2:2 chroma at 50/60 fps.
What's odd is that there is no official support for 10-bit 2160p with 4:2:2, regardless of frame rate, despite the fact that there is support for 12-bit 2160p with 4:2:2 chroma at all typical frame rates.
So, you are correct in saying that there was support for higher bit depths at 2160p24/25/30. However, you could only do 8-bit 2160p RGB/4:4:4 at 24/25/30 fps. For higher bit depths at 2160p, you had to use 4:2:2 chroma subsampling. That was the only minor detail that I was attempting to correct.
Regarding your example of 10-bit (deep color) 2160p24 output with 3 year old Blu-Ray players, I would be curious to know if the player and displays were actually using an unofficially supported format (10-bit 2160p24 with 4:2:2 chroma) or if it bumped the bit depth up to 12-bit to use an "officially" supported format (12-bit 2160p24 with 4:2:2 chroma)...