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Quote:
Originally Posted by pete4 /forum/post/21476057


The chart is saved in "PNG" format and I believe png uses lossless compression, so there should be no loss of detail or artifacts. I also noticed couple "errors", this could have been put there during chart creation, maybe.

I looked at the original charts on belle-nuit.com and they were created in .tiff with no artifacts. Would probably be pretty easy to recreate this test chart from the original charts on their site.


Regards,

bspvette86
 

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i find this all confusing.


what setting should my blu ray player be set at for watching blu rays? ycbcr or rgb?


i will have the sharp 60 632 and have a panny 110 player.


thx
 

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Quote:
Originally Posted by bspvette86 /forum/post/21476619


I looked at the original charts on belle-nuit.com and they were created in .tiff with no artifacts. Would probably be pretty easy to recreate this test chart from the original charts on their site.


Regards,

bspvette86

I modified the original 720p .tiff chart found on the belle-nuit.com site to be like the one we have been using in this thread. See attached.


Regards,

Karl


DOH!, the file uploader modified the file and introduced compression errors. changed from 1080p to 720p and re-attached image. Save the file to you desktop and view from your OS rather than through the website. The website viewer will show a modified version.
 

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This chroma thing only affects PC input, Blue Ray discs are always chroma subsampled so it really doesn't matter anyway. I would think RGB is more for computers and YCBR or properly YcBcR is more for video coding like BR but I could be wrong.

Quote:
Originally Posted by mark62 /forum/post/21476886


i find this all confusing.


what setting should my blu ray player be set at for watching blu rays? ycbcr or rgb?


i will have the sharp 60 632 and have a panny 110 player.


thx
 

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Sony 2010 46" NX711 passes the test in game mode and a couple other modes.
 

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You should use YCbCr output for Blu-ray and DVD; the encoded video is in YCbCr and a conversion to 8-bit RGB is slightly lossy. Better to let your TV do said conversion in its processing pipeline especially if it converts back to YCbCr internally.


However, you should probably use RGB output from computers even if you're playing Blu-rays and DVDs; YCbCr HDMI output means that the computer is likely doing YCbCr -> RGB -> YCbCr. Theoretically a hardware overlay based renderer could bypass the RGB step but compositing window managers (Windows since Vista, OS X since 10.2) break this. Anything that renders using OpenGL or Direct3D renders into RGB.


That said, it's unlikely you'd see any difference.
 

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Discussion Starter · #87 ·

Quote:
Originally Posted by bspvette86 /forum/post/21477025


I modified the original 720p .tiff chart found on the belle-nuit.com site to be like the one we have been using in this thread. See attached.

Thanks for catching that, I'll update the OP to point to your copy.
 

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Quote:
Originally Posted by thepoohcontinuum /forum/post/21479321


Thanks for catching that, I'll update the OP to point to your copy.

Here's a better screenshot of the Sony KDL46HX729 that is in focus and with a better exposure as well.
 

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Quote:
Originally Posted by thepoohcontinuum /forum/post/21479321


Thanks for catching that, I'll update the OP to point to your copy.

Or we could just create a new test file that would not infringe on anyone's copyright.... (see attached for example)


Regards,

bspvette86



added sample screenshots from Sony KDLXH729


 

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I don't see this, but I see this quote from article:


"If you choose to output 4:2:2 from your player to the display, then the display will need to do the scaling to 4:4:4 and then to RGB. If you output 4:4:4 to the display, the display will not need to do any scaling at all, but will need to do the conversion to RGB. If you output RGB to the display, then the display can avoid all conversion steps and send the signal right to the controller. No matter which you choose, the same conversion steps are still happening; all you are choosing is which device is performing the conversion."


which IMO would contradict your statement bellow.

Of course we do know for the fact, that a lot of TV's subsample signal to 422 and all I want to know is why and how to fix it. If it's hardware limitation, we kind of out of luck, if it's some software issue - to speed up calculations for frame interpolation in 120Hz TV's for example - I would gladly get rid of frame interpolation and all this 120Hz nonsense to get true full RGB pass through from computer.


Quote:
Originally Posted by WiFi-Spy /forum/post/21480778


Relevant article by Stacy Spears and Don Munsil:

http://spearsandmunsil.com/articles/...olorspace.html


Most video processors in TVs convert everything to 4:2:2 YCbCr internally before they do any scaling/processing.
 

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Quote:
Originally Posted by Lessen /forum/post/21478628


You should use YCbCr output for Blu-ray and DVD; the encoded video is in YCbCr and a conversion to 8-bit RGB is slightly lossy. Better to let your TV do said conversion in its processing pipeline especially if it converts back to YCbCr internally.

A 8-bit native sRGB signal has a significant loss upon conversion to 8-bit 4:4:4 YCbCr (luma codes are preserved, however many of the chroma codes end up not being used.). I dont believe that conversion back again has this same issue.


-k
 

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Great thread!


Here are my results for the Samsung LE32D550. That's the European (UK) LE model. Turns out it's totally different to the LN (US) model.


Sadly, it does not pass 4:4:4. Using an nV card, I even applied the EDID override fix, and I'm using the correct HDMI port (labelled DVI/HDMI).


Unlike the US model, there is no "input" section in the TV's menu.




In this first pic, notice that underneath the red tick, to the right of the vertical black line, there are blue subpixels turned on.




You can quite clearly see between the exclamation marks that the colour is not the correct background colour (grey).


Fortunately for me, this TV has 3 dead pixels in the centre. I will be returning this one for a refund.


Lastly, it is insanely hard to find a 4:4:4 TV in the UK. Insanely hard!
 

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I've picked up a Samsung 32LND550 (SQ04) and I can't seem to get 4:4:4 working.


I'm using a DVI to HDMI cable out of an ATI 6950 into the HDMI-1 (DVI) port and re-labeled it as DVI PC (tried PC also, appears to be the same). I've tried both EDID Override fixes. Here are some pics (
) (
)


If I turn the HDMI Black Level to Low it passes the Belle-nuit chart (
) however text still looks bad. I believe turning the Black Level to Low just crushes all detail in dark areas. If you notice the pixels around the 20 you can only see the green subpixel. Shouldn't you be able to see all 3?
 

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Quote:
Originally Posted by Ryzir /forum/post/21494964


I've picked up a Samsung 32LND550 (SQ04) and I can't seem to get 4:4:4 working.


I'm using a DVI to HDMI cable out of an ATI 6950 into the HDMI-1 (DVI) port and re-labeled it as DVI PC (tried PC also, appears to be the same). I've tried both EDID Override fixes. Here are some pics (
) (
)


If I turn the HDMI Black Level to Low it passes the Belle-nuit chart (
) however text still looks bad. I believe turning the Black Level to Low just crushes all detail in dark areas. If you notice the pixels around the 20 you can only see the green subpixel. Shouldn't you be able to see all 3?

I PM'd AVS member Antipodes, he seems to know the Samsung D550 really well, and he also happens to own the LG LK450. Hopefully he can offer some clues or insight.


I'm also going to link the extended info you posted at the [H]ard forums in case anyone else is willing to dissect the problem you're having.
 

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Quote:
Originally Posted by thepoohcontinuum /forum/post/21386795

T6) I want to use a HDMI->HDMI cable (because I want HDMI audio), can I still get 4:4:4?


From my experience and observations, the answer is no. As mentioned previously, *something* relating to HDMI audio extensions causes 4:4:4 to fail. Only by disabling the HDMI audio extensions (via a DVI->HDMI cable and/or EDID Override) will 4:4:4 become enabled. I have yet to encounter someone that has 4:4:4 working over a HDMI->HDMI (w/ HDMI audio) connection.

I can confirm this.


On my LG 42LK450 and ATI R6870, first I tried using HDMI->HDMI cable.


ATI CCC itself offers 4:4:4 subsampling, but it doesn't work.


Then I tried disabling EDID extensions. ATI CCC detected the TV as a regular monitor, but the picture was still 4:2:2.


Then I used a single-link DVI->HDMI cable and it worked instantly.


PS: Previously, with HDMI->HDMI cable, "PC mode" did 4:4:4, but the sharpness and other controls were disabled on the TV.


With DVI->HDMI I get 4:4:4 on every mode.
 
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