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HDMI Spec Upgraded To Support 'Deep Color'
writertype writes "If you own a digital television, there's a good chance it supports HDMI as an A/V interface. Well, for all you early adopters who bought an HDMI-less TV and regretted it later, the HDMI spec has been upgraded yet again, to version 1.3. Features include "deep color", or color depths beyond what the human eye can perceive, eight-channel audio support, among others. Interesting note: the PlayStation 3 supports deep color, according to the HDMI chief."
I figured someone would be confused by this. However, the article expains:
"The color bit depth [of today's displays] is typically 24-bits RGB - that gets you 16 million colors, and the human eye can distinguish that," Chard said. "That leads to scaling and onscreen effects which you can pick up. Either 36-bit or 48-bit RGB is beyond the ability of the human eye to distinguish."
Right now your eye can see the color transitions. The point is to make it so you can't see the transitions.
With current color depths, you can distinguish the difference between adjacent colors (in some limited portions of the field). By taking it to a depth where differences are imperceptible, you make things look smoother.
Essentially you want to have your colors go as deep as you need to to make differences imperceptible, which this (supposedly) does. After that going even deeper would be a waste.
rage, rage against the dying of the light
Now if you have 4090 possible values of red, your eye may not be able to perceive the difference between #1024 and #1032 individually. But when you make that large gradient while you will not be able to see the individual bands.
You've gone from blocky to smooth. Anywhere you want a gradient, this is good. Fading to black, the sky, etc. And let's not forget that this can give us better HDR.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
It doesn't increase the range of values that can be represented probably, just the resolution. (I don't mean resolution in the 1080p sense, but the bit depth of each pixel. E.G. the 24-bit part of 24-bit, 48 kHz.) It decreases the difference in between successive levels of each color.
Diverging slightly, this reminds me of the problem I ran into: I just bought a new house and setup a theater in it. As part of that, I bought a new Denon 3805, which has a feature where it converts all video inputs to HDMI, so I only have to run one relatively small cable to the projector, a Sharp XV-Z10000. It has a DVI input, but HDMI-DVI adapters are simple and readily available. Get everything hooked up, and find that my HD Tivo works, my progressive DVD recorder works, my old regular Tivo does not, and my non-progressive dvd player does not work. After some discussion with Crutchfield tech support (which almost made paying their premium worth it), it came out that the Sharp does not support interlaced input on the DVI port, and the Denon doesn't de-interlace in the up-conversion process. I nearly sent the receiver back, but the old one had some other problems the new one solved, and 99% of my watching is either the HD Tivo or the progressive dvd player, and running an extra S-video cable isn't that big of a deal, so I kept it.
It reared its ugly head again recently when I wanted to record something from the HD Tivo to the DVD recorder: I've not used the S-video connection for some time, and for various reasons, the cabling is still temporary. I had to tell the HD Tivo to switch to the S-video output to record to the DVD recorder, and found the S-video connection wasn't working. Try reconfiguring a Tivo without the video working!
I'm told by a knowledgeable friend that the DVI spec does not include interlaced input options. I assume HDMI must or the upconversion feature would be useless, but it's yet another reminder to double check interface compatibility when getting things you want to talk to each other.