Spears & Munsil Blu-ray Test Disc

[Geoff D]

Originally Posted by helvetica bold

Geoff buddy, you are correct!! I remember watching After Earth (not a great film) thinking the the PQ is very sharp but I don't see any amazing colors. So why don't games take advantage of the xvColor space? I think the only one was the last Devil May Cry. I heard that worked in xvColor but I could be wrong. Anyway I'm more concerned with the clipping when the Xbox One RGB full is on. Why does that happen but not on the PS4? Bravo to Sony engineering the W9 and PS4 make a nice combo! : D

I can't answer your Xbox question but as for movies, the modern trend is generally for desaturated colour, so even xvYCC isn't gonna turn something like Elysium into a Technicolour riot.

[Stacey Spears]

Wouldn't that indicate there is an error with the Xbox?

No. I actually work(ed) on the Xbox One for the last 2.5 years, its correct in that sense.

Per the HDMI spec, the term full means that 16-235 is expanded to 0-255 where everything that was originally below 16 and above 235 (240 for CbCr) is clipped. This applies to "video" content. The term limited means 1-254 is left untouched with the assumption that 0% is at 16 and 100% at 235. I say 0% and 100% instead of black and white. Values below 0% and above 100% should be preserved. I don't like the naming limited and full as it makes full sound like the better choice. I wanted to call it "Fool" on the Xbox.

I don't know what the PS4 does when set to full. I have not had one to look at yet from that point of view.

I looked long and hard for a display that would let me enable xvYCC, but all the ones I could find at the time simply had auto and off as options.

The wider gamut will come in deep cyans (think water in the south pacific), yellows (think sunflowers), blues (think peacock feathers), reds (think the busses in London). I am still looking for more examples so that I can capture for a 4k Blu-ray calibration disc, when that format comes to be sometime next year.

So a system that confines to video level will clip boxes 2,3 and 4?

What do you mean by 2, 3, and 4?

To be honest clipping isn't a bad thing because not many Blu-ray's have information outside of 16 and 240

Depends on if you clip in YCbCr or RGB. If you clip in YCbCr, not the end of the world. If you clip in RGB, you lose a lot of specular highlights. The thing about the RGB boxes on the clipping pattern is that Y is within 16-235 and CbCr are within 16-240. Nothing outside of that. It is only when converted to RGB that they go above 235. This was to demonstrate if clipping occurred in YCbCr or RGB.

The black clipping box is different. Cb and Cr are 33 or 35 (I forget at the moment) and Y is <16 in YCbCr. Once converted to RGB, all RGB values are above 16. The idea was to test for how a brightness control was implemented. If done properly, they should not clip. It was also to show how below 16 values in YCbCr impact above 16 values in RGB.

I can provide a lot of sample images of >235 once converted to RGB. In fact, I can demonstrate this with any Blu-ray. They all produce values above 235 in RGB. Maybe a B&W movie won't, but anything in color will.

[helvetica bold]

Thanks again Stacey! That's very cool you worked on the Xbox. Lastly, for gaming, you recommend keeping the Xbox set to RGB limited, correct? Oops just saw your edit, Ha,
I like the fool comment. 😊

[Stacey Spears]

Xbox 360 assumed all games were 0-255 and that was remapped to 16-235 if you had the HDMI levels set to standard. If you set to expanded, then games were left alone.

FYI
360 Standard == X1 Limited
360 intermediate == X1 (not implemented)
360 Expanded == X1 Full

Xbox One gives the game developers a choice. They tell us, through an API, if their game is native 0-255 or 16-235. Then we will remap, as appropriate, to match the video levels.

Make sense? If your display is calibrated for 0% at 16 (RGB Limited) then leave it there for games too, otherwise things will look overly contrasty and dark stuff will be crushed.

PCs often work in the other direction by default. The desktop is 0-255, so video is remapped to 0-255. The exception was Media Center, which kept video at 16-235.

[Tech-UK]

I remember seeing a post on AVS which I think you posted Stacey, of the Cars Blu-ray and it showed colours that were outside. Do you still have those images?

[helvetica bold]

Stacey thanks again for the fantastic info!
If I have HDMI dynamic range set to full on my TV, contrast looks great and black levels appear inky. Nothing looks crushed. It was only on the RGB clipping test where things went flat and that's in the xbox's BluRay app.
I can't recommend the Sony W900a enough, it's a fantastic TV. I'm also enjoying the New Xbox as well just want to get the most out of it.

[Stacey Spears]

I don't know if these show up when you are not logged into skydrive.

Hot green is one or more pixels in an RGB triplet is <16. Hot pink is one or more RGB pixels in an RGB triplet above 235. Clipping may cause a hue shift for a given pixel.

Cars:


Here is a histogram view:


Dark City:


Dream Girls:


The Office:


Pirates of the Caribbean:


Coral Reef:


Signs:


Storm Chaser:


In the very early days of HD DVD / Blu-ray, WHV was running some encoder tests for Ned Price. I was told that Ned looked at the video on a WFM and rejected saying that someone had clipped the video. He did not even look at the display. It was not the encoder, but a pre-processing step they had done at the time. They removed the step and he was happy. I forget if it was Constantine or Batman Begins.

[Tech-UK]

They are displaying fine.

Thanks for posting them.

[helvetica bold]

Stacey I'm hope I'm not getting too off topic but will the Xbox 360 output xvColor? There's a game called Devil May Cry that plays in xvColor. It's one of the very perhaps only game to take advantage of the color space. I'm playing the demo on PS3 and it looks beautiful. Extremely saturated hues. This off screen shot doesn't do it justice. I want to buy it for the 360 if it can handle the colors pace.

[Stacey Spears]

I don't know the answer, but I suspect it will be no. I have not touched a 360 in a couple of years.

[Zman2k2]

I read your statements on the XBoxOne Stacey, and I want to thank you. Although I didn't use your disc to tune my TV, changing the settings on the XBox to what you suggested was exactly what I needed. I had the color set to "PC" instead of "tv", which was crushing my blacks. I then set color space to 36-bit, and my colors were easier to adjust, and simply more vibrant. Thank you so much for those two pieces of info. It made my movie watching that much better.

[ckenisell]

Stacey,

I have a really hard time adjusting colors in general. I am a graphic artist and totally understand the grayscale, setting brightness and contrast are easy, but I can never seem to get the colors right. I look through the blue gels provided by various calibration discs, but I can never get it perfect.

I have a Panasonic plasma VT30 that was isf calibrated and it seems much more "yellow" or warm than my other two sets that have not been professionally calibrated. My other three sets (two led's and one projector) are slightly more blue or cool in color.

Any tips for properly setting the color? In all three displays, there are main color setting and then "Advanced" settings that go way in depth, but I don't understand how they relate to one another. I always start in "Standard" mode and never use settings such as warm, cool, Cinema, etc.

Thanks!

[steve1971]

Originally Posted by helvetica bold

Stacey thanks again for the fantastic info!
If I have HDMI dynamic range set to full on my TV, contrast looks great and black levels appear inky. Nothing looks crushed. It was only on the RGB clipping test where things went flat and that's in the xbox's BluRay app.
I can't recommend the Sony W900a enough, it's a fantastic TV. I'm also enjoying the New Xbox as well just want to get the most out of it.

Hey helvetica I agree with you on the W900A. As an owner I cant recommend it enough myself. So you have dynamic range on full? How does it look on full? And would you recommend that I put mine on full as well? Let me know.

[Stacey Spears]

I have a really hard time adjusting colors in general. I am a graphic artist and totally understand the grayscale, setting brightness and contrast are easy, but I can never seem to get the colors right. I look through the blue gels provided by various calibration discs, but I can never get it perfect.

Blue filters are not reliable. They only work on a small number of displays. Do you see black or are there colors leaking through when running our filter test?

The chroma subsampling also creates a line between the colors, which can make it difficult to set correctly. This is just a limitation of 4:2:2 and 4:2:0 sources.

Can you provide more info on what you are having trouble with? Is it setting color, tint, or both?

[Tech-UK]

Stacey, on the colour space pattern, the square in the middle with the two lines inside, are all the lines 1 pixel wide?

And I suppose there should be a 1 pixel gap between the lines inside to the actual square?

What if its 2 pixels wide? Does that mean additional sharpening is being applied?

[Stacey Spears]

Originally Posted by Tech-UK

Stacey, on the colour space pattern, the square in the middle with the two lines inside, are all the lines 1 pixel wide?

And I suppose there should be a 1 pixel gap between the lines inside to the actual square?

What if its 2 pixels wide? Does that mean additional sharpening is being applied?

Are you talking about the cross hatch in the very center of the pattern? White horizontal and vertical line on a black background? That is a solid black background with a single pixel horizontal and vertical line on top. So yes, 1 pixel wide and 1 pixel high.

It was there to look for panel misalignment in the center or chromatic aberration.

Is the image being scaled at all?

If you click on the top image in this article http://www.spearsandmunsil.com/portf...color-space-2/ it will display a full resolution version of the pattern so you can see it on you computer monitor. You may need to right mouse click and save as and view in another viewer if your computer is lower resolution.

[Tech-UK]

On your website on the page 'Choosing a Color Space, 2nd Edition', are the vertical and horizontal examples correctly labelled?

The 3 boxes featuring vertical lines, has the description; 'High Frequency Horizontal Resolution Burst'.

[Tech-UK]

Originally Posted by Stacey Spears

Are you talking about the cross hatch in the very center of the pattern? White horizontal and vertical line on a black background? That is a solid black background with a single pixel horizontal and vertical line on top. So yes, 1 pixel wide and 1 pixel high.

It was there to look for panel misalignment in the center or chromatic aberration.

Is the image being scaled at all?

If you click on the top image in this article http://www.spearsandmunsil.com/portf...color-space-2/ it will display a full resolution version of the pattern so you can see it on you computer monitor. You may need to right mouse click and save as and view in another viewer if your computer is lower resolution.

Yes, I am talking about the cross hatch.

Yeah, on my computer monitor the white lines are one pixel wide. Whereas on my Kuro they are 2 pixels wide.

Sharpness is set to -15 on the Kuro and 0 on my BD player. But the Kuro is set to Enhancer mode 1 (hard).

I might see if setting it to Enhancer mode 2 (natural) helps.

[Stacey Spears]

You have to show me which box you are looking at.

I was talking about the box in the very center of the pattern. There is no label.

[Tech-UK]

Originally Posted by Stacey Spears

You have to show me which box you are looking at.

I was talking about the box in the very center of the pattern. There is no label.

I am referring to two separate things.

Sorry.

See my post above regarding my first question.