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Sorry, but nVidia Control panel also have similar video settings. I'm not sure what your system is setup correctly because Kodi doesn't apply color correction for full range setting
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2015-12-21, 09:08
(This post was last modified: 2015-12-21, 10:03 by _Shorty.)
Standard non-DX11 v15.2 and previous versions display the correct black level. It is only the v16 beta that is showing the elevated black level. My system is set up correctly. And it is calibrated with a meter. Would you like the fL values for regular black with v15.2 and v16 beta black?
Nvidia output settings are set for RGB full range output.
Nvidia video settings are set to adhere to the application's settings.
Kodi is set for full range output.
This is the optimal setup for this system. TV is calibrated using AVS709 patterns played back in Kodi. And as I said, black levels are correct in 15.2 with this setup. Setting to RGB Limited or YCbCr (edit: typo) in Nvidia's control panel is sub-optimal, as it results in a round-trip conversion from 0-255 -> 16-235 -> 0-255 if you use either of those limited settings. But this is besides the point.
The point is, Kodi v16 betas are not outputting the correct video levels. It appears to be outputting 16-235 video even when it is set to output 0-255 video, with the limited range setting being turned off in Kodi. This is exactly the way video looks in 15.2 if the system is calibrated for 0-255 but you set Kodi to use limited range 16-235. Because the system is calibrated for a black of 0 and Kodi is instead feeding the TV a black of 16 it results in a noticeably bright grey instead of black.
When you turn on the limited range setting in Kodi it behaves in 'video pass-through' mode, correct? Outputting video with 16-235 levels. This is expected. But when the limited range setting in Kodi is turned off it is supposed to expand the 16-235 video data to 0-255 and output it as 0-255. This is not happening. With the limited range setting turned off it is outputting 16-235 video when it is supposed to be outputting 0-255 video. I also have a suspicion that I tested with the limited range setting turned on and it made the blacks even brighter, but I will go confirm whether or not this is the case right now.
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2015-12-21, 09:55
(This post was last modified: 2015-12-21, 10:23 by _Shorty.)
Well, at least I was wrong about v16 beta 4 with limited being even brighter. It was actually the DXVA test version you just posted that gets even brighter. Here's some brightness measurements I just took now. edit: The black image is a 1920x1080 bmp file with RGB 0-0-0. And all the measurements in Kodi are with the AVS709 black test video.
Black image shown on desktop in Windows Image Viewer
0.022 fL
v15.2 full range with AVS709 black test video
0.022 fL
v15.2 limited range
0.231 fL
v16 beta 4 full range
0.230 fL
v16 beta 4 limited range
0.229 fL
v16 DXVA test version full range
0.229 fL
v16 DXVA test version limited range
0.654 fL
So, given that, I decided to take a guess and measure a couple more images on the desktop. I made a couple of grey images to test. One with RGB of 16-16-16 and one with 32-32-32 to see if I get similar brightness measurements with those.
16-16-16
0.239 fL
32-32-32
0.719 fL
Something's definitely being altered incorrectly in Kodi v16, and especially in that latest DXVA test version. You would think that the test version and limited range would match the 32-32-32 value, since it seems to be converting black to 16 twice, but it did not. So I decided to test with at least one more image on the desktop, but ended up with two more because the first one at 31-31-31 was still brighter than DXVA-test-limited's black.
31-31-31
0.676 fL
30-30-30
0.658 fL
So that last value is close to the DXVA-test-limited value, which would suggest that for some reason that test version's black is being converted to 30 with that limited range setting turned on. In any event, both full range and limited range are incorrect in all v16 betas, including that DXVA test version. In the case of beta 4 both full range and limited range are outputting black as 16, when only limited range should be doing so. But v15.2 behaves as expected, with full range black being 0 and limited range black being 16.
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One question, just to be sure, if you open a black image in the picture viewer in Kodi 16, is the image shown brighter? Did I understand you correctly?
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Also just checked this now, still in the DXVA test version, and all with full range:
Render method DXVA & allow DXVA2 on
too bright
Render method pixel shaders & allow DXVA2 on
too bright
Render method software & allow DXVA 2 on
too bright
Render method DXVA & allow DXVA2 off
too bright
Render method pixel shaders & allow DXVA2 off
black is correct
Render method software & allow DXVA2 off
black is correct
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Hmm, interesting. Thanks.