[mythtv-commits] Ticket #7307: Add ITU BT709 colorspace support and studio levels (RGB 16-235) for VDPAU playback

[MythTV]

#7307: Add ITU BT709 colorspace support and studio levels (RGB 16-235) for VDPAU
playback
------------------------------+---------------------------------------------
 Reporter:  jyavenard         |       Owner:  ijr    
     Type:  enhancement       |      Status:  new    
 Priority:  minor             |   Milestone:  unknown
Component:  MythTV - General  |     Version:  unknown
 Severity:  medium            |     Mlocked:  0      
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 By default VDPAU uses PC RGB levels (0-255 range), this is good for your
 typical PC monitors, but TV's are usually calibrated for different levels
 (black at 16 and white at 235). Using PC levels with a TV expecting studio
 levels result in poor black and white levels (crushed).

 This could be fixed by changing the contrast and brightness default value,
 but obviously this isn't ideal.

 Another issue is that HD videos uses a different colorspace than SD (ITU
 BT.709 vs ITU BT.601). VDPAU by default uses BT601, so all colours with HD
 videos are actually wrong ; they would be shifted, slightly under or over
 saturated. This is particularly noticeable with skin tones.

 So ideally, you would want to use BT601 colorspace for SD videos and BT709
 for HD videos.

 This patch adds ITU BT709 video support and RGB studio levels to VDPAU
 playback.

 Parameters are set using the custom filter option in the deinterlacer
 configuration screen.
 Utilities/Setup -> Setup -> TV Settings -> Playback -> Playback Profiles
 -> Custom Filters

 studio: will prevent converting to PC levels
 colorspace=n will set the colorspace to be used.
 n=0: will use BT709 for HD videos and BT601 for SD
 n=1 (default): will always use BT601
 n=2: will always use BT709

 Example:
 Custom Filters: studio,colorspace=0

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Ticket URL: <http://svn.mythtv.org/trac/ticket/7307>
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