[FFmpeg-devel] [PATCH]VDPAU patch for MPEG1/2 decoding, round 1

[Gwenole Beauchesne]

Hi,

On Mon, 5 Jan 2009, Reimar D?ffinger wrote:

>> What about such occurrence in mpegvideo.c? Enumerating all codec_id would
>> be rather suboptimal. Or, is it considered sane only in that file?
>
> To my knowledge that's exactly two codec ids.
> But if that is too much, you could define a macro.

For mpegvideo.c, VA API will use the same code path (i.e. avoid drawing 
the edges). And the bitwise CODEC_CAP_HWACCEL is simpler to write than 
enumerating all VA API codecs too (MPEG2, MPEG4, VC1).

A macro could be fine, though this will me 5 tests (a single line won't be 
enough).

> But to be honest I can't tell for sure what makes sense, since it is a mystery
> to me what the purpose of all those xvmc_acceleration,
> CODEC_CAP_HWACCEL, CODEC_CAP_HWACCEL_VDPAU etc. is supposed to be,

I think all current HW accel implementations are inspired by (ancient?) 
XvMC. AFAIK, the CODEC_CAP_HWACCEL is e.g. used in vd_ffmpeg.c to setup 
::get_buffer(), ::release_buffer() et al.

For xvmc_acceleration, I think it was used as a means to enable/disable 
XvMC acceleration without specifying the codec explicitly? Though, I don't 
know if this worked in practise.

Regards,
Gwenole.