0-255 vs. 16-235 on HTPC, trying to understand what is going on - AVS Forum
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post #1 of 157 Old 12-01-2008, 04:41 AM - Thread Starter
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I ve finally managed to get a totally stutter free HTPC where I playback 3 kinds of video files:
1. Standard def. dvd material, 2. .wmv HD files and 3. .mkv HD files.

I use windows XP with sp3 installed on have a ATI HD 4350 video card. My HTPC is connected to my digital projector, the Mitsubishi HC7000 (HDMI out on HD4350 to HDMI1 in on HC7000). I use the latest driver for the 4350, 8.10driver (note that the 8.11 driver does not support the 4350! I ve checked this!).

As for software playback on my HTPC I use Media Player Classic HC with Haali's Video Renderer (and for .mkv files Core AVC 1.8.5 comes in).

The problem' I now run into is the so called Luma Range' in Haali's Video Renderer (and Input Levels and Output Levels in the Core AVC options). All three (Luma Range, Input Levels and Output Levels) can be set to TV (16-235) or PC (0-255). I do know that it is the color range of the video, but would like to know 2 things:

1. What is the best to pick if you have the ATI HD4350 and a digital projector like me for Luma Range, Input Levels and Output levels?
2. When I select 16-235 the picture that my projector displays becomes more dark and selecting 0-255 makes the picture look more grey and brighter. What should I select?

Thanks for all help!
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post #2 of 157 Old 12-01-2008, 05:15 AM
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There is no single right or wrong answer for this.

Source video files - DVD, HD-DVD, Blu-ray and Broadcast TV MPEG2, H264 and VC-1 will have their video stored in 16-235 format on-disc. This is what broadcast facilities and studios use as standard for digital video. Black is at 16, White is at 235. (There are values below black and above white to allow for undershoot and overshoot on high frequency edges without clipping, which would otherwise cause ringing etc. NB the black at 16 is nothing to do with composite NTSC 7.5IRE black level set-up) If you look at an SDI or HD-SDI signal in a broadcast facility or output from a VTR it will be 16-235 (or in some cases a 10 bit variant)

Some newer file-based video formats DON'T always use 16-235 though - and also SD and HD YCrCb to RGB mappings are different to each other. (601 vs 709 colourspace)

Sources can run at either 0-255 or 16-235 format. Original DVI output PCs ran 0-255 - as they were not designed with video in mind, and Windows ran with a 0-255 24bit desktop (8 bit 0-255 in each colour channel). Blu-ray players, satellite receivers, DVD players etc. with digital HDMI outputs would normally default to 16-235 output (as contained in the original broadcast or on the original disc) as this is the broadcast/production standard. (NB On-disc it is actuall YCrCb - with Y 16-235 and CrCb 16-240, but in RGB space it is 16-235 in all channels)

Displays can run in either 0-255 or 16-235 format in the same way. Most PC monitors with DVI-D inputs will usually expect a 0-255 input as a default, and most HDMI-equipped TVs will expect 16-235. That isn't to say that it isn't always possible to correctly calibrate a 0-255 display to correctly display a 16-235 input or vice versa - with the correct brightness (black level) and contrast (white level) settings it is often possible to correct for this (and many modern displays can have different brightness/contrast settings for different inputs). HOWEVER if you are switching HDMI multiple sources via an AV Amp into a single HDMI input, you really want your video levels to be consistent between sources.

So...

You have multiple points in the chain where 16-235 and 0-255 video can be used.

My understanding is that for consistency between applications and methods of display (though not always the highest quality), it is better for Windows to run internally in 0-255 mode. Thus either your video codec OR your overlay processor will ideally convert from 16-235 to 0-255 BUT NOT BOTH. Similarly your output video driver will then convert from 0-255 back to 16-235 for output if your display is a 16-235 model.

This MAY mean that there is some scaling going on, which could introduce some banding and truncation due to quantisation errors (as we don't have 30 or 36 bit internal RGB in many PCs yet - just 24 bit - which is 8 bit per channel).

Other options are possible - but they can leave you with crushed blacks or grey blacks if you aren't careful.

I'm not familiar with the Haali renderer I'm afraid - but if you only watch 16-235 sources, it may be worth setting it to 16-235 to see if you get consistent black levels between video playback and native Windows display (which won't use the renderer)

Using Vista EVR and an ATI driver registry hack to force 16-235 colour space conversion on SD content I have consistent black and white levels across content and apps now. I am able to set the output colour space of my HDMI output to RGB 16-235 in the drivers - and this works well for me.
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post #3 of 157 Old 12-01-2008, 06:29 AM
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Thanks for this informative post sneals2000!
Highly appreciated.
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post #4 of 157 Old 12-01-2008, 09:13 AM
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Quote:
Originally Posted by sneals2000 View Post

Some newer file-based video formats DON'T always use 16-235 though

Which ones don't?

Thanks

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post #5 of 157 Old 12-01-2008, 09:16 AM
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Ones encoded by people who didn't do it right.

See what an anamorphoscopic lens can do, see movies the way they were meant to be seen
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post #6 of 157 Old 12-01-2008, 09:20 AM
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Quote:
Originally Posted by stanger89 View Post

Ones encoded by people who didn't do it right.

Those certainly, I think MJPEG has different scales but I wasn't aware of any others.

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post #7 of 157 Old 12-01-2008, 09:24 AM
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A lot of xvids used to be done in 0-255, because they were to be viewed on PC screens. The pirates seem to have standardised to 16-235 now though :-)
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post #8 of 157 Old 12-01-2008, 11:58 AM
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My tv (Samsung LE46A656) has an option for HDMI blavk level "normal" or "low". When its set to normal its expecting 0-255, when set to low its expecting 16-235.
The tv is basically my pc monitor, but I am also watching hd movies through my pc.
If I set my tv to expect 0-255 and my pc to output 0-255, will the colorspace be accurate both when watching movies and when used as a normal pc?
In ATI catalyst there is an option to select colorspace with the new driver version. Should I set it to auto, or 0-255?
Also, in CoreAvc, there is an option for 0-255, 16-235 and auto. What do I select there?
The same in ffdshow. Right now it is set to YV12
I am using winxp, so I think I am using VMR9 renderer.

Thanks. This is really complicated. Too many options. Too many places where things can go wrong!
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post #9 of 157 Old 12-01-2008, 01:30 PM
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Quote:
Originally Posted by karoloydi View Post

If I set my tv to expect 0-255 and my pc to output 0-255, will the colorspace be accurate both when watching movies and when used as a normal pc?

You'll get banding as a result of level expansion.

If I select 0-255 in the Nvidia drivers, there are obvious banding artifacts in grey ramps that go away when I revert to 16-235.

The downside of calibrating for 16-235 is that non-video material (applications, games, photos, and what not) will be clipped.

You can have your cake and eat it too, if you set up two profiles on your display, and switch according to the source.
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post #10 of 157 Old 12-01-2008, 02:03 PM
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Quote:
Originally Posted by nm88 View Post

You'll get banding as a result of level expansion.

If I select 0-255 in the Nvidia drivers, there are obvious banding artifacts in grey ramps that go away when I revert to 16-235.

The downside of calibrating for 16-235 is that non-video material (applications, games, photos, and what not) will be clipped.

You can have your cake and eat it too, if you set up two profiles on your display, and switch according to the source.

Although when it comes to LCD display you are going to get some expansion anyway. Since to get black you need to get the LCD crystals fully opaque, that is the display digital zero. The brightness and contrast controls will expand the video.

So some of this banding may show up in a frame capture, but an actual calibrated LCD will look very similar.

Also with vista and nvidia HDMI output is already compressed to 16-235 even at the desktop, so expanding video to 0-255 actually IS 16-235, I have no idea how much data is lost in the math behind the scenes, but if you go 16-235 in the control panel, you'll be compressing the video even further.

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post #11 of 157 Old 12-01-2008, 02:07 PM
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Quote:
Originally Posted by JohnAd View Post

Which ones don't?

Thanks

John

Those encoded for 0-255 viewing on PCs - and those generated with 0-255 sources (animation and other graphics produced on a PC may not have been 16-235 processed).

Also xvCC (or whatever seemingly-random combination of xyvc it is...) uses the full 0-255 range AIUI - so some AVCHD files produced by camcorders that use this format may also use the wider range.
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post #12 of 157 Old 12-01-2008, 02:38 PM
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A timely post as I've been pulling my hair out over this very issue the last few days with a v similar setup to the original poster. Using Win XP, an ATI 4650 and outputing to a plasma screen.

I've been trying to calibrate my screen to use video levels using the standard greyscale ramps with btb/wtw picture content. The ramps are saved in mp4 format so using coreavc to decode, vmr9 renderer. I've done the ATI hack to ensure standard expansion to 0-255 across SD and HD content, and have set avivo video color to brightness 16, contrast 86 which I've read ensures a consistent output of video levels to the screen.

So far so good I think, but I've got thoroughly confused about the correct settings in coreavc for input and output levels. Using autodetect coreavc is selecting video levels in and out, which makes sense as it's video level content being inputed. However, in doing this the ramps are being clipped at 16 and 235 - no matter how much I turn up brightness or contrast I cannot see the content below/above these levels.

Thinking this couldn't be right I changed the input on coreavc to pc level ie 0-255 leaving output at video levels. The content is no longer being clipped but now I'm not sure what I'm calibrating to. Am I actually calibrating to PC levels? Focusing just on the black level, if I calibrate so that I can't see the bars below 16 with coreavc set to pc level input I get one level of brightness on my screen. If I then switch coreavc back to video levels then picture is much darker and I have to turn brightness way up just to see the bars down to 16 (and obviously can't see anything below 16 due to the clipping). Which level is right?

Sorry for the long post but grateful for any help from anyone who's read this far!
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post #13 of 157 Old 12-01-2008, 02:46 PM
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Quote:
Originally Posted by arfster View Post

A lot of xvids used to be done in 0-255, because they were to be viewed on PC screens. The pirates seem to have standardised to 16-235 now though :-)

I've sometimes seen the opposite: 16-235 source compressed again, yelding something with even less range (32-220?) that forces you to fix your brightness value on the TV no matter what.
Or maybe the pirates were trying to defeat mandatory expansion by graphics cards?
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post #14 of 157 Old 12-01-2008, 03:21 PM
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Quote:
Originally Posted by nm88 View Post

You'll get banding as a result of level expansion.

If I select 0-255 in the Nvidia drivers, there are obvious banding artifacts in grey ramps that go away when I revert to 16-235.

The downside of calibrating for 16-235 is that non-video material (applications, games, photos, and what not) will be clipped.

You can have your cake and eat it too, if you set up two profiles on your display, and switch according to the source.

How come when I play movies in my laptop there is no banding? Shouldnt it be the same?
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post #15 of 157 Old 12-01-2008, 03:48 PM
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Quote:
Originally Posted by karoloydi View Post

How come when I play movies in my laptop there is no banding? Shouldnt it be the same?

Because what you would see will only show up in static images where you can examine the issue. In moving images you won't notice.

Also I don't believe you can correctly setup an LCD unless you get a 10bit panel (in respect to the greyscale ramp) and then once you get a 10bit panel, the panel will expand the levels correctly.

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post #16 of 157 Old 12-01-2008, 04:18 PM
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Quote:
Originally Posted by sotti View Post

Because what you would see will only show up in static images where you can examine the issue. In moving images you won't notice.

Also I don't believe you can correctly setup an LCD unless you get a 10bit panel (in respect to the greyscale ramp) and then once you get a 10bit panel, expanding the levels is fine.

Oh, my lcd (Samsung LE46A656) is 10 bit. So it should be fine if I used 0-255 levels both for pc and for movies, shouldn't it?
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post #17 of 157 Old 12-01-2008, 04:27 PM
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Quote:
Originally Posted by karoloydi View Post

My tv (Samsung LE46A656) has an option for HDMI blavk level "normal" or "low". When its set to normal its expecting 0-255, when set to low its expecting 16-235.
The tv is basically my pc monitor, but I am also watching hd movies through my pc.
If I set my tv to expect 0-255 and my pc to output 0-255,

I'd have expected it to be the other way around. I love it when they use such descriptive terms.

Quote:


...will the colorspace be accurate both when watching movies and when used as a normal pc?
In ATI catalyst there is an option to select colorspace with the new driver version. Should I set it to auto, or 0-255?

The best way (near as I can tell) to get accurate colors is to do the following:
Use Catalyst 8.11
Connect via HDMI (using the ATI dongle or HDMI output set to HDMI mode)
Set Pixel Format to either Studio RGB, or one of the Component options.
Set your video players to not expand.

What this does, near as we've been able to tell, is compress the desktop to 16-235, and "do nothing" with video (ie leaves black @ 0, white @ 235). It seems to fix everything, unfortunately I haven't had much of any time to play with my HTPC since I installed them. But they do display the desktop and HD correctly with my projector set to "7.5 IRE" (which means it expects 16-235), and I think even SD looked correct.

See here:
http://www.avsforum.com/avs-vb/showt...t=pixel+format

Finally someone has put forth the effort to do this, we've only been waiting 10 years for it

Quote:


Also, in CoreAvc, there is an option for 0-255, 16-235 and auto. What do I select there?
The same in ffdshow. Right now it is set to YV12

16-235, or "TV" depending on how it's labeled.

Quote:


Thanks. This is really complicated. Too many options. Too many places where things can go wrong!

Yeah, it's a case of two different standards chosen. 16-235 came from the analog TV world where it was necessary to define digital coding "below black" and headroom above white analog signals.

0-255 came from the PC world where there was no need to maintain headroom.

Problems ensued when video started being done on PCs and apparently nobody put any serious thought into how the two different worlds should be handled.

See what an anamorphoscopic lens can do, see movies the way they were meant to be seen
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post #18 of 157 Old 12-01-2008, 05:10 PM
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Quote:
Originally Posted by stanger89 View Post


What this does, near as we've been able to tell, is compress the desktop to 16-235, and "do nothing" with video (ie leaves black @ 0, white @ 235). It seems to fix everything, unfortunately I haven't had much of any time to play with my HTPC since I installed them. But they do display the desktop and HD correctly with my projector set to "7.5 IRE" (which means it expects 16-235), and I think even SD looked correct.

16-235 has NOTHING to do with 7.5 IRE.

7.5 IRE is a US-NTSC composite specific voltage set-up to separate black level from blanking. Japanese NTSC, and all variants of PAL and SECAM don't use it and have black and blanking at the same level. There is no 7.5IRE in any standard digital component representation of a TV signal - not in SD or HD, in the US or overseas. (The only caveat is some domestic camcorders when used to record DV from a US NTSC composite source ignore 7.5 IRE - i.e. treat the US NTSC as Japanese NTSC-J - and thus record with a set-up black level)

Black at 16 in Rec 601 (and Rec 709 AIUI) is used in all digital component formats - 480i/525, 576i/625, 720p and 1080i/p. It is there to avoid truncating undershoots and overshoots on high-frequency edges - which if clipped would cause ringing in A/D and D/A conversions.

It is REALLY important not to confuse 7.5 IRE set-up on composite with 16-235 digital video representation - they are two totally separate things.
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post #19 of 157 Old 12-01-2008, 05:13 PM
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Quote:
Originally Posted by el Filou View Post

I've sometimes seen the opposite: 16-235 source compressed again, yelding something with even less range (32-220?) that forces you to fix your brightness value on the TV no matter what.
Or maybe the pirates were trying to defeat mandatory expansion by graphics cards?

That appeared to be the case with EVR rendered content in Vista Media Center on my ATI HD 3200 IGP install. SD content had grey blacks and dull whites, whilst HD content, and other bits of Windows content were fine - and the output was 16-235 not 0-255 (as it didn't require any contrast or brightness changes when switching between it and HDMI outputs from a satellite receiver and a Blu-ray player). It appeared as if the SD content were being handled as 0-255 internally even though it was 16-235 at source, whilst the rest of Windows and HD content was correctly displayed in a 0-255 colour space (with the HD stuff converted from 16-235?). The output of this 0-255 stuff was then being re-compressed to 16-235 colour space. (The 16-235 to 0-255 to 16-235 is a potential source of quantisation error induced banding, but at least ensures consistent levels across all Windows output...)

It transpires that there is an issue with the EVR - and that ATI drivers have a registry fix that will ensure SD 16-235 content is correctly handled in the same way as HD stuff. It is something like the BT601CSC registry entry...
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post #20 of 157 Old 12-01-2008, 06:03 PM
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Quote:
Originally Posted by sotti View Post

Also with vista and nvidia HDMI output is already compressed to 16-235 even at the desktop, so expanding video to 0-255 actually IS 16-235, I have no idea how much data is lost in the math behind the scenes, but if you go 16-235 in the control panel, you'll be compressing the video even further.

I have no idea what you're talking about.

I use Vista, with an Nvidia 8600 GTS and the latest WHQL drivers. When I set the driver to 0-255, I get level expansion, and serious banding as a result (viewed on a grey ramp, either on DVD or BD test discs).

When I set it to 16-235, I don't, and the banding is nearly non-existent.

Also, when I set it to 16-235, it is obviously doing just that, because I need to adjust the brightness and contrast controls on the display to compensate, as compared to the 0-255 setting.

If 16-235 were "compressing the video even further" as you claim, I would seeing exactly the opposite.
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post #21 of 157 Old 12-01-2008, 06:07 PM
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Quote:
Originally Posted by karoloydi View Post

Oh, my lcd (Samsung LE46A656) is 10 bit. So it should be fine if I used 0-255 levels both for pc and for movies, shouldn't it?

Your panel will NOT make the problem go away, because the expansion is done on your PC, then sent as an 8-bit signal. So that banding will come from the source, and there's nothing you can do about it.

There's no reason to over-complicate this. Load a grey ramp, try one setting, then try the other, calibrating black and white for each of course. Use the one that looks better, with less banding. It will take all of one minute, less time than to post here.
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post #22 of 157 Old 12-01-2008, 06:16 PM
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Quote:
Originally Posted by sneals2000 View Post

16-235 has NOTHING to do with 7.5 IRE.

It is REALLY important not to confuse 7.5 IRE set-up on composite with 16-235 digital video representation - they are two totally separate things.

Yup, I understand, that's why I put "7.5 IRE" in quotes. Unfortunately BenQ confused the two (or overloaded the wording) in the W5000's menus. The "IRE" setting in the menu has the effect of switching between 0/7.5 IRE input for analog, and on digital inputs, it switches between 0-255 ("0 IRE") and 16-235 ("7.5 IRE"). It's perfectly obvious what's happening when you switch between the two, even if the labels aren't right.

Unfortunately there just is no good way to label such a control. "Normal" vs "Expanded" would give novices the false impression that 0-255 ("Expanded") is better, since it's "expanded". "Normal" and "Low" are no better. I guess PC and Video are perhaps the best though still potentially confusing (guess there's no way around that).

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post #23 of 157 Old 12-01-2008, 08:50 PM
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Quote:
Originally Posted by nm88 View Post

I have no idea what you're talking about.

I use Vista, with an Nvidia 8600 GTS and the latest WHQL drivers. When I set the driver to 0-255, I get level expansion, and serious banding as a result (viewed on a grey ramp, either on DVD or BD test discs).

When I set it to 16-235, I don't, and the banding is nearly non-existent.

Also, when I set it to 16-235, it is obviously doing just that, because I need to adjust the brightness and contrast controls on the display to compensate, as compared to the 0-255 setting.

If 16-235 were "compressing the video even further" as you claim, I would seeing exactly the opposite.

Well how are you wired?
What is your display?

it is a known issue that the desktop for nvidia with HDMI is compressed, on the otherside people with HDMI equipped monitors are bemoning the fact taht their displays are grey blacks. I didn't really notice till I loaded up XP and was like WTF happened to my black levels, why are they so dark now.

Also protected path video (Blu-ray) is still expanded based on 0-255 and not the 16-235 the desktop is sitting at. so no matter what your BD won't look the same as your DVD (assuming you didn't convert your BD to MKV thus bypassing the protected path).

my experience is with the 8200 chipset, full patch vista OS and a whole suite of nvidia drivers including the latest WHQL drivers and some of the beta drivers from nvnews.net forums.

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post #24 of 157 Old 12-01-2008, 09:21 PM
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Quote:
Originally Posted by nm88 View Post

Your panel will NOT make the problem go away, because the expansion is done on your PC, then sent as an 8-bit signal. So that banding will come from the source, and there's nothing you can do about it.

This is correct, a 10bit panel will be better for banding, but sending it the original 16-235 signal and then letting its 12bit engine + 10bit panel sort our the rendering details will give the best picture.

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post #25 of 157 Old 12-01-2008, 11:04 PM
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Originally Posted by sotti View Post

Well how are you wired?
What is your display?

Vista, Nvidia 8600 GTS, and Sharp GP1U connected through HDMI.

The desktop is not compressed. It is at 0-255. Only the video is 16-235.
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Also protected path video (Blu-ray) is still expanded based on 0-255 and not the 16-235 the desktop is sitting at. so no matter what your BD won't look the same as your DVD (assuming you didn't convert your BD to MKV thus bypassing the protected path).

My BD discs look exactly the same as the DVDs in terms of black/white levels, using hardware acceleration.

I'm using the same DVE grey ramp pattern for DVD and BD, so if there were a difference, I'd see it immediately.
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post #26 of 157 Old 12-01-2008, 11:05 PM
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Originally Posted by sotti View Post

This is correct, a 10bit panel will be better for banding, but sending it the original 16-235 signal and then letting its 12bit engine + 10bit panel sort our the rendering details will give the best picture.

A 10 bit panel cannot undo rounding errors that occur at the source, because the source is sending 8 bits. If you expand 16-235 to 0-255 on your PC, you're locking in those errors and that banding. A 10 bit panel can only undo errors caused at the panel.
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post #27 of 157 Old 12-02-2008, 01:17 AM
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Anyone got any thoughts on my post #12 further up the thread. It's got buried very quickly! Thanks
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post #28 of 157 Old 12-02-2008, 03:13 AM
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Quote:
Originally Posted by sotti View Post

it is a known issue that the desktop for nvidia with HDMI is compressed, on the otherside people with HDMI equipped monitors are bemoning the fact taht their displays are grey blacks. I didn't really notice till I loaded up XP and was like WTF happened to my black levels, why are they so dark now.

Also protected path video (Blu-ray) is still expanded based on 0-255 and not the 16-235 the desktop is sitting at. so no matter what your BD won't look the same as your DVD (assuming you didn't convert your BD to MKV thus bypassing the protected path).

my experience is with the 8200 chipset, full patch vista OS and a whole suite of nvidia drivers including the latest WHQL drivers and some of the beta drivers from nvnews.net forums.

Is this everyone's experience?

I was about to build a new HTPC based on the nVidia 9400 chipset - as I wish to get multichannel PCM and decent SD and HD de-interlacing and possibly some SD post-processing etc. I also need to output 1080/24p - and most reports I've read suggest that nVidia chipsets are better in this regard.

My current HTPC is ATI 780G based HTPC and after quite a lot of research I found the BT601CSC hack (that properly handles SD content the same way as HD) and the latest Catalyst 8.11 drivers also allow you to set your output colour space (YCrCb 4:2:2 or 4:4:4, RGB Video 4:4:4 or RGB PC 4:4:4)

I hadn't definitively heard that the nVidia suffered the same inconsistent black/white level handling (i.e. failing to correctly handle 16-235 video and treating it as 0-255 with set-up blacks and dull whites) between SD and HD video content (such that black levels varied between SD and HD/Windows native stuff)

This appears to be the case from your report and may mean I don't go ahead with the nVidia build... Grrr...

Has anyone managed to fix this without requiring profile changes or adjusting their TV between SD and HD stuff.

Is there still not an IGP solution with ? :
  1. Proper 24p support
  2. Decent SD de-interlacing performance (with vector adaptive stuff)
  3. Multichannel PCM over HDMI support
  4. Correct SD and HD black level handling
  5. Proper output colour space selection (i.e. between YCrCb and RGB, between video and PC levels, and between 4:2:2 and 4:4:4)

It appears that nVidia solutions meet the first three, and ATI solutions the final two...
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post #29 of 157 Old 12-02-2008, 03:33 AM
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Quote:
Originally Posted by nm88 View Post

Vista, Nvidia 8600 GTS, and Sharp GP1U connected through HDMI.

The desktop is not compressed. It is at 0-255. Only the video is 16-235.My BD discs look exactly the same as the DVDs in terms of black/white levels, using hardware acceleration.

I'm using the same DVE grey ramp pattern for DVD and BD, so if there were a difference, I'd see it immediately.

What players are you using for DVD and BD? What renderers are you using (if you have a choice)?

Is your HDMI output running with 0-255 colourspace (i.e. to get Windows blacks and whites correctly you have to modify the TV brightness/contrast compared to 16-235 source - like a satellite receiver or standalone HDMI BD or DVD player)?

Is your SD and HD video stuff is being left 16-235 within this 0-255 space (so that it appears grey and washed out in comparison to standard Windows content, but that when fed to your display expecting 16-235 you thus get SD and HD video content consistently handled with black blacks (though not crushed) and white whites (though not clipped), but Windows stuff is crushed and clipped?
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post #30 of 157 Old 12-02-2008, 11:08 AM
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Quote:
Originally Posted by sneals2000 View Post

What players are you using for DVD and BD? What renderers are you using (if you have a choice)?

For BD and HD-DVD playback, PowerDVD 7.3 (or TMT, which I used for a while, and gave me the same result).

For DVD, I use MPC (non-HC) and Nvidia Purevideo, with VMR9 to preserve hardware acceleration.
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Is your HDMI output running with 0-255 colourspace (i.e. to get Windows blacks and whites correctly you have to modify the TV brightness/contrast compared to 16-235 source - like a satellite receiver or standalone HDMI BD or DVD player)?

Yes.
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Is your SD and HD video stuff is being left 16-235 within this 0-255 space (so that it appears grey and washed out in comparison to standard Windows content, but that when fed to your display expecting 16-235 you thus get SD and HD video content consistently handled with black blacks (though not crushed) and white whites (though not clipped), but Windows stuff is crushed and clipped?

Yes. That's what I was saying about the desktop/video tradeoff.
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