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HDMI 2.0 officially announced

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Re: HDMI 2.0 officially announced

#121

Post by ChuckMcM »

throwaway2048 wrote: post #116
ChuckMcM wrote: post #91

Earlier quoted context omitted.

8 bits isn't "current", if you want "current" you get 10 bit panels. If you want "better than bargain basement" you get 10 bit panels. At least where I live one of the differences between the TVs that CostCo sells and the ones that others sell are 8 bit (CostCo) vs 10 bit (others) panels.

what kind of signal are you feeding a 10 bit panel? RGB is only 8 bit so any claimed 10 bit display is only post processing at best.

That is a good question. And strangely not as straight forward as I might like. "RGB" is 8 bit but video is not encoded with RGB, it is encoded YbCbCr [1], and the conversion from Chroma space to RGB space is fractional and depends on the Kr and Kb constants.

The math supports converting a YbCbCr 'pixel' into a 30 bit RGB pixel if your conversion constants allow for it. What is unclear is when quantization noise from the compression of the chroma signal shows up as bit instability in the resulting conversion cycle.

[1] http://en.wikipedia.org/wiki/YCbCr

Re: HDMI 2.0 officially announced

#122

Post by sillysaurus2 »

hoka wrote: post #113
coldpie wrote: post #108

Earlier quoted context omitted.

I'm on the market for a decent monitor. Are there any brands that you /like/, or is it simply a matter of choosing the least terrible?

I have an HP LP2475W and a Dell U2412M; generally, among the IPS class, the consensus seems to be that HPs have more outputs and a better UI. Some of them are wide-gamut, however, which turns off a few purchasers. Research as to whether or not wide-gamut is important/detrimental to you. I'd say go for 24s or a 30; if you have the 27 you'll just wish you had the 30 :-p but definitely go IPS, they are fantastic. I have…

Actually, the Dell U30xx is worse than the U27xx. The color fidelity isn't as good. (This only matters if you calibrate your monitor.)

Re: HDMI 2.0 officially announced

#123

Post by sillysaurus2 »

rootbear wrote: post #72

This race for more pixels is misguided. The change I most want to see is deeper pixels, at least 10bpp, preferably more. I'm getting really tired of all the banding I see on what should be smooth gradient images. If a landscape aspect image is P pixels wide then to display a gray scale gradient, black to white, you need ceil(log2(P)) bits per pixel. So a "2K" display needs 11 bits, "4K" needs 12, etc. Then each colum…

As soon as there's the slightest amount of noise, it's impossible to discern between 8bpp vs 10bpp. And real-life applications will almost always have noise.

Re: HDMI 2.0 officially announced

#124

Post by kibibu »

sp332 wrote: post #24
kibibu wrote: post #22

Earlier quoted context omitted.

Interesting that a "virtual speaker set" won over higher-order Ambisonics (representing incoming audio as spherical harmonics). I wonder if it just boils down to easier engineering.

Ambisonics requires a lot of actual speakers to have a large (say, couch-sized) "sweet spot" where the directional audio sounds any good.

I find this curious, as you should in theory be able to map your 30 speakers to SH coeffs if you are using high-enough order SH (although 4th degree SH needs 25 coefficients so I guess there's not enough savings)

Re: HDMI 2.0 officially announced

#125

Post by brigade »

rootbear wrote: post #72

This race for more pixels is misguided. The change I most want to see is deeper pixels, at least 10bpp, preferably more. I'm getting really tired of all the banding I see on what should be smooth gradient images. If a landscape aspect image is P pixels wide then to display a gray scale gradient, black to white, you need ceil(log2(P)) bits per pixel. So a "2K" display needs 11 bits, "4K" needs 12, etc. Then each colum…

This has been in the HDMI spec for 7 years already and most high-end TVs support 10-12 bit input. And lower end TVs it doesn't matter anyway. Also TVs often use at least 10 bits between internal processing steps.

Anyway, what you want is happening for 4k - Rec. 2020 mandates at least 10bit for 4k

Re: HDMI 2.0 officially announced

#126

Post by stan_rogers »

Shorel wrote: post #96
rootbear wrote: post #72

This race for more pixels is misguided. The change I most want to see is deeper pixels, at least 10bpp, preferably more. I'm getting really tired of all the banding I see on what should be smooth gradient images. If a landscape aspect image is P pixels wide then to display a gray scale gradient, black to white, you need ceil(log2(P)) bits per pixel. So a "2K" display needs 11 bits, "4K" needs 12, etc. Then each colum…

I don't get any banding when I connect my old 21" CRT via DVI to my current PC and set the display to 10bpp (32bits/ true color in MS terminology). What we need is a replacement for LCD technology.

32-bit is 8 bits per colour channel (24-bit) plus an 8-bit alpha (transparency) channel, not 10-and-a-bit bits per channel. The alpha isn't (normally) sent to the display device, it's used to render overlapping elements at the display generation level (video card). Good LCDs can easily render the full colour depth with headroom to spare. Higher-end graphics monitors are often 12-bit (the extra range is used for calibration/display accuracy, not necessarily for greater depth).

Re: HDMI 2.0 officially announced

#127

Post by brigade »

ChuckMcM wrote: post #91
rootbear wrote: post #85

Earlier quoted context omitted.

Good point. But the current 8 bits per pixel is definitely too few.

8 bits isn't "current", if you want "current" you get 10 bit panels. If you want "better than bargain basement" you get 10 bit panels. At least where I live one of the differences between the TVs that CostCo sells and the ones that others sell are 8 bit (CostCo) vs 10 bit (others) panels.

Note that the panels are very unlikely to be true 10-bit; they're almost certainly 8-bit with temporal dithering. And the cheap panels are 6-bit with temporal dithering to 8-bit.

Re: HDMI 2.0 officially announced

#128

Post by erikig »

sliverstorm wrote: post #117
SiVal wrote: post #114

Earlier quoted context omitted.

Honest question, does 4K and up really make sense for private use? It's a good question, but my answer is definitely, Yes. My ideal work station would be a room with a wall-sized 8K touch-screen monitor covering the wall in front of me. I would have an adjustable table with a comfy chair and treadmill looking over the table and across the room at the wall screen. Lower the table and sit in the chair. Raise the table…

Have you used multi-monitor setups before? Anything more than about two screens, and I personally find myself getting really annoyed because I have to turn my head instead of moving my eyes. I feel like a full-wall monitor would be even worse.

I've been using a 39" Seiki 4K monitor for my application development 'needs' for about 2 weeks and I have to say 4K is a substantial step forward from 3 or 4 1080p screens. HDMI 2.0 is great because - especially for desktop use - we can increase from the 30Hz limit of HDMI 1.4.

Take a look at reviews of the Seiki 4K unit from private users for a feel of how things are coming along: http://www.amazon.com/Seiki-Digital-SE39UY04-39-Inch-Ultra/p...

Re: HDMI 2.0 officially announced

#129

Post by mbell »

papercrane wrote: post #27
kayoone wrote: post #25

Honest question, does 4K and up really make sense for private use ? I am pretty sure from the distance that you usually watch 1080p content, you wont see a difference to 4K content at all. Of course for big presentations and conference setups i see the usecase, just not for the consumer mainstream. 4K would also set back game console performance by a huge margin, if they will ever adopt it. So i am not really convinc…

> Honest question, does 4K and up really make sense for private use ? For big monitors I think it does. Even if 4k doesn't make sense, the increased bandwidth is a win as the previous HDMI spec couldn't drive a 2560x1440 or 2560x1600 monitor at 60hz, and those resolutions definitely make sense to me for computer monitors.

> as the previous HDMI spec couldn't drive a 2560x1440 or 2560x1600 monitor at 60hz

That has been supported by HDMI since 1.3, since around 2006.

2560×1600p75 @ 24bit is about the highest standard resolution you can pump through HDMI 1.3.

Re: HDMI 2.0 officially announced

#130

Post by sp332 »

kibibu wrote: post #124
sp332 wrote: post #24

Earlier quoted context omitted.

Ambisonics requires a lot of actual speakers to have a large (say, couch-sized) "sweet spot" where the directional audio sounds any good.

I find this curious, as you should in theory be able to map your 30 speakers to SH coeffs if you are using high-enough order SH (although 4th degree SH needs 25 coefficients so I guess there's not enough savings)

Like I said, that requires a lot of physical speakers, not just encoded data.
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