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Taylor: Avoiding Jitter in Composited Frame Display

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 2, 2012 21:48 UTC (Sun) by Fowl (subscriber, #65667)
In reply to: Taylor: Avoiding Jitter in Composited Frame Display by alonz
Parent article: Taylor: Avoiding Jitter in Composited Frame Display

"Overlay" video rendering has been depreciated for quite a long time. The compositor might have special knowledge of video, but it's certainly used.


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Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 3, 2012 7:22 UTC (Mon) by elanthis (guest, #6227) [Link]

Absolutely. Windows still uses compositing and all the full DXGI framework for video; it has to in order to offer the kind of modern user experience that we expect. The DRM paths just restrict things so that the CPU can't read back the decoded image buffers on the GPU, and likewise requires that the scanout device be a "secured" path.

Direct3D 11.1 (and DXGI 1.2) expose a lot more control over the whole process, offering a pretty good API for intermixing restricted content playback with programmable general-purpose graphics units. There's plenty of documentation up on MSDN about the new API additions and the overall architecture of their encrypted video playback support, including D3D API and driver changes necessary to support intermixing video playback with shaders and the rest of the GPU. Most of it just boils down to restricting what buffers you can write authenticated video content into and how those buffers are allowed to be accessed.

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 3, 2012 11:53 UTC (Mon) by daniels (subscriber, #16193) [Link]

"Overlay" video rendering has been depreciated for quite a long time.

It really hasn't. All current-generation GPUs have dedicated YUV overlay units, since they can do vastly better colourspace conversion and filtering, which makes a huge difference in image quality. Even putting that aside, you get an enormous benefit in terms of power usage, so pretty much all embedded/mobile/media-class chipsets vastly prefer the overlays.

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 3, 2012 20:55 UTC (Mon) by airlied (subscriber, #9104) [Link]

except for anything in desktop space,

no new nvidia or amd gpu has had yuv overlay in years. Since DX9 cards I'd guess.

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 3, 2012 21:08 UTC (Mon) by daniels (subscriber, #16193) [Link]

Hm, isn't UVD an overlay?

Taylor: Avoiding Jitter in Composited Frame Display

Posted Dec 3, 2012 21:11 UTC (Mon) by zlynx (subscriber, #2285) [Link]

As I recall reading, the new cards have exactly the same feature, they just do it with a texture surface and a shader program these days.

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