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Here's what I understand so far:
Movies use studio color (16 - 235)
PCs use RGB color (0 - 255)
I've searched the forums and it seems like XBMC expands every movie during playback from 16 - 235 to 0 - 255. Is this true?
Does that mean I should set my TV to expect RGB (0 - 255) colors?
I've noticed that VDPAU Studio Color Correction option, but it sounds like XBMC would expand videos to 0 - 255 then shrink them to 16 - 235 causing two different color conversions.
I'd like my movies (720p MKVs mostly) to display as accurately as possible.
Thanks for any help!
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I would like more info on this as well. Is there a way to make linux/nvidia output 16-235 exclusively? Or is it stuck at 0-255?
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elupus
Team-XBMC Developer
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xbmc always expands to 0-255, so your TV should be set full range input.
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Thanks for that information!
How does that work? Does XBMC assume every movie is encoded as 16 - 235 and then forcefully expands it? (I'm not criticizing, just wondering how it works!)
Does "VDPAU Studio Color Correction" actually perform two color conversions like I speculated in the OP?
EDIT: Also, doesn't expanding 16 - 235 to 0 - 255 result in colors 0-15 and 236-255 being dropped? (eg. blacker than black and whiter than white)
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elupus
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- BTB and WTW are indeed dropped, so it's not optimal.
- Most movies are 16-235, the ones that are not are marked so, and then we don't expand
- "VDPAU Studio Color Correction" does only YUV->RGB but keep it in limited range, so no double conversions are happening. GUI is still in fullrange thou so that will look wrong if you have your TV set to recieve limited range.
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bobo1on1
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You don't want whiter than white and blacker than black, most of the time they're lossy encoding artifacts.
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I'm just curious, but how can you tell if a movie is encoded as 16 - 235? Is there a flag inside H.264 files, etc?
Also, is your opinion that the best quality is to just leave XBMC as normal and set my TV for 0 - 255 (full) range?
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bobb0
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i say go for simple. do what looks best to your eyes.
if you can't tell the difference, then is it really worth the effort?
i find the vdpau studio correction causes everything to be brighter and washed out, so i don't use it.