[vlc-devel] [PATCH 03/34] video context: add a function to test if 2 context are similar

[Rémi Denis-Courmont]

Le tiistaina 12. marraskuuta 2019, 17.06.46 EET Steve Lhomme a écrit :
> On 2019-11-12 11:23, Rémi Denis-Courmont wrote:
> > VDPAU buffers are tied to a VDPAU device instance. You cannot use them
> > across different VLC video contexts. I doubt you can do that with NVDEC
> > either.
> > 
> > It might be possible with DRM or maybe not, but even then I doubt that
> > the similarity callback can actually be implemented...
> > 
> > So I don't really see the point over a straight pointer equality test.
> 
> A video context created from a decoder device is likely to be compatible
> with another video context created from the same decoder device. This
> works in NVDEC and in D3D11. Decoder devices can probably check for
> equality with just a pointer.

Well it could be. But then again, I don't exactly follow why you would have 
separate video contexts for the same decoder device. At least in VDPAU, device 
and context are essentially the same thing (a VdpDevice handle and its 
dispatch table). I would think NVDEV would work the same way.

Do we actually have a case where the video context will wrap some child object 
of the decoder device, and not the same thing?

-- 
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