[FFmpeg-devel] [PATCH] AVHWAccel infrastructure v2

Gwenole Beauchesne gbeauchesne
Sat Sep 26 14:20:52 CEST 2009


Le 26 sept. 09 ? 13:52, M?ns Rullg?rd a ?crit :

> Gwenole Beauchesne <gbeauchesne at splitted-desktop.com> writes:
>
>> - Get pixels back from GPU memory when the user requested it
>
> Isn't that generally very slow?

Yes, that's why it's done on-demand, when the user really really wants  
it and fills in the right HWACCEL_ATTR_GET_PIXELS attribute. Now, I  
have not properly measured the slow-down to say "very". By default,  
the pixels are not read back.

Oh, yes, I did some time ago on a 8600 GT (G84 core) and an H.264  
1080p @ 8 Mbps video. CPU was a dual core Opteron.

In VLC with vaGetImage():
    min 24.7%  max 63.5%  avg 30.5%

In MPlayer with vaPutSurface():
    min  0.1%  max  7.6%  avg  0.6%

In MPlayer with Xv:
    min 43.3%  max 72.5%  avg 68.4%




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