[mythtv-users] VDPAU, etc (hasn't been 'HDHomeRun - Comcast shut off clear QAM' for a while)

[Michael T. Dean]

On 12/12/2013 02:43 PM, Jay Ashworth wrote:
> From: "Michael T. Dean"
>> VDPAU is Video Decode&  Presentation API for Unix.
>>
>> The Video Decode part is the part that pushes the encoded video to the
>> hardware decoder to decode it.
>>
>> The Video Presentation part is the part that allows drawing the
>> decoded video frames on screen.
>>
>> So, the presentation part replaces the
>> (designed-for-another-simpler-era's-video) Xv rendering with a
>> more-full-featured rendering and drawing framework (that allows for
>> much better OSDs and such).
> Could not having enabled that with the proprietary drivers be a cause for
> VBI tearing?
>
> Cause I have that now, among other weirdness in .26

AIUI, any time you use VDPAU rendering, you will get video output 
without tearing, regardless of whether you've enabled "sync to vblank" 
on the nvidia drivers or not (because the drivers know it's video and 
automatically sync screen refreshes appropriately).  If you use OpenGL 
rendering (definitely) or Xv rendering (I think?), you must enable "sync 
to vblank" on the nvidia proprietary drivers or you will get tearing.

Mike