nVIDIA RSX - Native RGB color space output?

[michaeljamesjohnson]

I need your help guys...

Does anyone know (with proof) the native RGB color space output from the PS3 nVIDIA RSX in the XMB and games?

I cannot seem to find proof myself, but I happen to think it is 0 to 255 (RGB FULL).

I do have proof that SD-DVD & Blu-Ray discs use YCbCr 16 to 235.

I am in the middle of a big debate on the AVSForums and I need to find out the native output for the RSX in XMB and games with some sort of proof to back it up. At this point, I do not care who wins the debate....I just want to know so I set up my gear correctly.

FYI - My Sony XBR4 has a RGB FULL setting as well.

 

[manux]

I need your help guys...

Does anyone know (with proof) the native RGB color space output from the PS3 nVIDIA RSX in the XMB and games?

I cannot seem to find proof myself, but I happen to think it is 0 to 255 (RGB FULL).

I do have proof that SD-DVD & Blu-Ray discs use YCbCr 16 to 235.

I am in the middle of a big debate on the AVSForums and I need to find out the native output for the RSX in XMB and games with some sort of proof to back it up. At this point, I do not care who wins the debate....I just want to know so I set up my gear correctly.

FYI - My Sony XBR4 has a RGB FULL setting as well.

Output is as it can be configured from the settings. I would say you are wrong... Check the manual from here. PS3 can output full rgb or limited. Also Y Pb / Cb Pr / Cr is supported via HDMI.

As to what is the native framebuffer format, I guess that heavily depends on the application/game. My guess would be 32bit rgba for framebuffer format but it could easily vary a lot between applications and their needs. It's just as a pc in that sense.

Configuring your display, that depends what your display supports best. I would say use test images and go through settings and see what looks best. For example my display looks better on rgb limited than full(yes, crap...).

 

[Arwin]

Yes, whatever looks best on your TV is the best setting. The color space can probably be converted lossless anyway

I think I read somewhere that the RSX uses YUV internally though, i.e. that is how it physically stores its color values in VRAM. But it could just as well be that I completely misunderstood that (technical) post.

By the way 0-255 RGB is definitely wrong.

 

[ERP]

Games will render to RGBA for the most part.
Blending and Goraud shading can do weird things in YCbCr space.
Doesn't surprise me that movies are decoded to YCrCb since thats less work than doing the RGB conversion.

 

[michaeljamesjohnson]

So you are saying that there is no *best* setting (RGB FULL or RGB LIMITED) if your display supports both?

I just figured that games and the XMB probably use more than the 16 to 235 color space, so setting your display and the PS3 to RGB FULL would be best since that is 0 to 255 (and this is assuming your display supports it - like my XBR4 or a dedicated computer monitor).

Isnt RGBA 0 to 255 plus an alpha channel?

 

[ERP]

You're probably better set to full.

Most games don't assume 15 is black but I know that the PS3 output does some correction on the output, and it's different to the 360's output....

IME most devs use shitty (relatively) displays badly calibrated, it's not like you're missing out on the directors vision if you have the wrong setting, just use what works best for a particular title.

 

[novcze]

with that limited output you don't lose anything, because PS3 make correction from 0-256 to 16- 235, question is why Sony bother with limited output and why they even make limited output by default at launch of PS3 without choice

 

[manux]

with that limited output you don't lose anything, because PS3 make correction from 0-256 to 16- 235, question is why Sony bother with limited output and why they even make limited output by default at launch of PS3 without choice

Because there are displays that actually show better picture with limited mode than in full. I would wager that most displays actually are better off set to limited... Not so perfect displays assume limited rgb output and cut off all the colours below and above the limited range. My hdtv for example is such a device.

How is it bad that sony actually supports meaningful configurations and let's user select what is appropriate for him? If user doesn't want to bother about that then just leave settings to auto.

edit. Even in full mode I would expect many displays not to support real 8bits per component output. It's good test to try out with sample image and see how many different shades of single r,g,b colours one can see. I bet not 256 shades per component

 

[novcze]

Because there are displays that actually show better picture with limited mode than in full. I would wager that most displays actually are better off set to limited... Not so perfect displays assume limited rgb output and cut off all the colours below and above the limited range. My hdtv for example is such a device.

How is it bad that sony actually supports meaningful configurations and let's user select what is appropriate for him? If user doesn't want to bother about that then just leave settings to auto.

edit. Even in full mode I would expect many displays not to support real 8bits per component output. It's good test to try out with sample image and see how many different shades of single r,g,b colours one can see. I bet not 256 shades per component

have options is not bad (my english is ;-), i just wanna pointed out what you suggested in edit.
In time of PS3 launch, there was not so many high-quality lcd tv, maybe therefore Sony launch PS3 with limited output without choice (first fw.). My hdtv accept full rgb, but definitively don't showing all 256 shades per component and i think all internal processing in tv is not done in 8 bits per component

 

[TrungGap]

My hdtv accept full rgb, but definitively don't showing all 256 shades per component and i think all internal processing in tv is not done in 8 bits per component

It's my understanding that most HDTV process image with 8bit/component, however it's the panel that doesn't display full 8bit/component. Many low-end LCD panel before 2006/2005 can display only 7bit. So it's not the internal, but the panel that is the limiting factor here.

However, Plasma, CRT and Project HDTV didn't have that problem.

 

[novcze]

There is picture with 256 shades of red color, what i see is passing between shades with some stripes, but not so bad as this (which is 128 shades)

 

[djskribbles]

i don't know if this helps or not, but i have the option to set my Samsung LNT4042H to full or limited in its menu labeled "HDMI Black Level: Normal/Low" (but now i'm unsure as to which is which). i have my samsung set to "HDMI Black Level: Low" and my PS3 set to RGB Limited and my black level matches YCbCr output (confirmed by using Avia to calibrate both YCbCr and with BR/DVD set to RGB Limited). i also set my TV to "Normal" and my PS3 to RGB Full and my settings also match YCbCr levels.

 

[michaeljamesjohnson]

AVSForum members are convinced that the PS3 simply stretches the RGB Limited "16 to 235" color space to "0 to 255" when turning on RGB Full on both the display and the PS3. They claim the PS3 still sends a "16 to 235" signal no matter what. At least this is the way I understood it. I have several questions...

1. Do you think XMB and PS3 games use sRGB?

2. Do you think the XMB and PS3 game sources will really take advantage of RGB 0 to 15 and 236 to 255 when turning on RGB FULL? Maybe it is not a source thing, but instead the way the RSX renders and ouputs the color space?

3. Are there any RGB or YCbCr "Deep Color" sources yet and if so, how do you turn this feature ON/OFF in the PS3? This is a color depth feature, and I dont see any settings. My XBR4 supports 10bit color sources rather than just 8bit. The HDMI.org site advertises that this is a PS3 feature.

4. Do any YCbCr sources (SD-DVD/Blu-Ray) take advantage of x.v.Color (aka xvYCC)? This is a color gamut setting that extends YCbCr from 16 to 235 to 0 to 255 kinda like the RGB LIMITED vs. FULL setting. My XBR4 and Onkyo receiver both have x.v.Color settings I can turn on. HDMI.org says that this is a PS3 feature.

5. Is "Super White" the only PS3 x.v.Color setting? I cannot find any others. The setting only seems to help in calibration on Blu-Ray discs. It passes BTB 0 to 15 and WTW 236 to 255 info when calibrating. It does not seem to effect the actual movie itself.

 

[michaeljamesjohnson]

Maybe this will make it easier to understand...assuming I am understanding correctly:

RGB (PS3 games?/XMB?)

Limited: 16 to 235​

Full: 0 to 255​

Deep Color: 10, 12 or 16 bits per channel of color depth instead of the standard 8.​

YCbCr (SD-DVD/Blu-Ray)

Recommendation ITU-R BT.601 (i.e. SD-DVD): 16 to 235​

Recommendation ITU-R BT.709 (i.e. Blu-Ray): 16 to 235​

xvYCC (aka x.v.Color): 0 to 255​

Super White​

Deep Color: 10, 12 or 16 bits per channel of color depth instead of the standard 8.​

The bottom line is that I want to know if there is any reason to have RGB FULL, x.v.Color/Super White & Deep Color turned on if the PS3, receiver & display support it? What sources out there have these features besides some Sony Camcorders??? HDMI.org makes it sound like PCs and the PS3 have sources.

 

[pux]

AVSForum members are convinced that the PS3 simply stretches the RGB Limited "16 to 235" color space to "0 to 255" when turning on RGB Full on both the display and the PS3. They claim the PS3 still sends a "16 to 235" signal no matter what. At least this is the way I understood it. I have several questions...

1. Do you think XMB and PS3 games use sRGB?

Yes.
The native format (or framebuffer format) for XMB and Game is sRGB.
And sRGB is identical with full-range RGB in PS3.
So you had better turn on "full-range RGB" if you have a receiver that also suppors full-range RGB, and you get lossless singnal.
The reason why limited-range RGB (that offers degraded signal) is default is that limited-range RGB is defined as default format in HDMI specification.
Even more full-range RGB is not valid format before HDMI1.3 (except DVI compatible output)

2. Do you think the XMB and PS3 game sources will really take advantage of RGB 0 to 15 and 236 to 255 when turning on RGB FULL? Maybe it is not a source thing, but instead the way the RSX renders and ouputs the color space?

XMB and Game always render in sRGB regardless of what range you choose.
HDMI Tx stretches to limited-range RGB if limited-range RGB is set.

3. Are there any RGB or YCbCr "Deep Color" sources yet and if so, how do you turn this feature ON/OFF in the PS3? This is a color depth feature, and I dont see any settings. My XBR4 supports 10bit color sources rather than just 8bit. The HDMI.org site advertises that this is a PS3 feature.

It is auto-configured if your receiver supports deep color.
There are few deep color source though, deep color & limited-range RGB provieds almost the same quality as 8bit full-range RGB.
The only REAL deep color source I Know is "Foldingf@Home".

4. Do any YCbCr sources (SD-DVD/Blu-Ray) take advantage of x.v.Color (aka xvYCC)? This is a color gamut setting that extends YCbCr from 16 to 235 to 0 to 255 kinda like the RGB LIMITED vs. FULL setting. My XBR4 and Onkyo receiver both have x.v.Color settings I can turn on. HDMI.org says that this is a PS3 feature.

It is auto-configured, if "Super White" is set and your receiver supports xv.Color.
But both DVD and BD have not support xv.Color yet.
AVCHD is only xv.Color source at present I suppose.
XMB and Game never send YCbCr, that means, neither send xv.Color.

Just for reference, the framebuffer format of BD/DVD Player is YCbCr, but
the one of XMB Media Player is full-range RGB.

One more thing, xv.Color extends gamut but color-range is still the same as the one of YCbCr, while full-range RGB extends color-range but gamut is the same as the one of limited-range RGB.

5. Is "Super White" the only PS3 x.v.Color setting? I cannot find any others. The setting only seems to help in calibration on Blu-Ray discs. It passes BTB 0 to 15 and WTW 236 to 255 info when calibrating. It does not seem to effect the actual movie itself.

Yes.
And because again, DVD and BD have not supported xv.Color yet though,
they usually contain Super White signal.
but unfortunately many LCD TVs can not handle Super White signal.
Try legacy CRT TV, or long for Organic EL

Sorry for my poor english.
Thanks.

 

[novcze]

The only REAL deep color source I Know is "Foldingf@Home".

Hi pux,
can you please explain how you know about PS3 Folding@Home client to be Deep Color source and is 10-bit or more?
Thanks in advance.

 

[grandmaster]

I am in the middle of a big debate on the AVSForums and I need to find out the native output for the RSX in XMB and games with some sort of proof to back it up. At this point, I do not care who wins the debate....I just want to know so I set up my gear correctly.

FYI - My Sony XBR4 has a RGB FULL setting as well.

I think someone's been at the crackpipe at AVS...

Full 24-bit RGB lossless shots for your delight. Give them a good looking-over in Photoshop. Everything looks in order to me.

 

[manux]

I think someone's been at the crackpipe at AVS...

Would be nice if you could take similar shots while playing dvd/blu-ray to verify movie playback colour performance.

 

[sir doris]

My understanding of this is that Sony have chosen confusing terms with limited and full. Maybe normal and computer would have been better?

The above makes sense to me in terms of AV but i'm not sure about how games are displayed.

The explanation (for Blu-ray/ DVD) that was given to me is this:

Broadcast/ AV systems have RGB values which corespond to 16 - 235, therefor this is the range of values available on a Bluray or DVD.

All modern HDTV's should be setup to accept 0-16 as black and 235-255 as white. Thus should be set to limited.

Computer displays are designged to accept values from 0-255 there for if connected to a PS3 (set as limited) true blacks and whites will NOT be available. However setting the PS3 to full will remap the 16-235 range to 0-255, allowing the full colour spectrum on a computer monitor.

Likewise connecting a New HDTV to a PS3 set to full, will result in crushed blacks as grey values are mapped to maximum black, and light colours are mapped to full white. This may initially look better as it makes the image more viberant but you loose LOTS if not MOST of the detail in dark or light images.

However I have no idea how this works with games which I assume would have values ranging from 0-255.

Do games even change dependant on the limited full full setting? If you change the output mode to YCbCr does this only affect blurays/ DVDs?

If limited is used does the 0-255 range get mapped back to 13-235 for output?

 

[SonComet]

I think someone's been at the crackpipe at AVS...

Full 24-bit RGB lossless shots for your delight. Give them a good looking-over in Photoshop. Everything looks in order to me.

I don't know. I have no way of doing a side by side, but I do have a calibration profile on my monitor for both video and computer use (ie 16-235 and 0-255). When I am in my computer mode the Full screens look correct. When on my video profile 16-235 looks the same as Full when viewed on my computer profile and now Full has horribly crushed black. My TV supports both Full and Limited, but I leave it on Limited just to avoid any potential hassles of the hdmi mode glitching when switching between games and movies. I don't want to have to manually check the hdmi mode every time just to be sure.