[FFmpeg-devel] [FFmpeg-cvslog] lavc/qsvenc: add VDENC support for H264

[Li, Zhong]

> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Li, Zhong
> Sent: Friday, January 11, 2019 10:29 AM
> To: FFmpeg development discussions and patches
> <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [FFmpeg-cvslog] lavc/qsvenc: add VDENC
> support for H264
> 
> > From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On
> Behalf
> > Of Carl Eugen Hoyos
> > Sent: Friday, January 11, 2019 1:06 AM
> > To: ffmpeg-devel at ffmpeg.org
> > Subject: Re: [FFmpeg-devel] [FFmpeg-cvslog] lavc/qsvenc: add VDENC
> > support for H264
> >
> > 2019-01-10 14:51 GMT+01:00, Linjie Fu <git at videolan.org>:
> >
> > > +#if QSV_HAVE_VDENC
> > > +    { "low_power", "enable low power mode(experimental: many
> > > +limitations by
> > > mfx version, BRC modes, etc.)", OFFSET(qsv.low_power),
> > > AV_OPT_TYPE_BOOL, {
> > > .i64 =  0 }, 0, 1, VE},
> > > +#endif
> >
> > This seems wrong to me: The visibility of an option should probably
> > not depend on configuration details (the effect can of course depend
> > on many details).
> >
> > Carl Eugen
> 
> That's is just a remind that this feature has some limitations. The configures
> are just to make driver to support this feature.
> In ffmpeg level, the only thing we should do IMHO is to query MSDK/Driver
> capability and report an error message if not supported.
> And it was done:
> https://github.com/FFmpeg/FFmpeg/blob/395e8a53fa0266f26581f3e9752b
> 0dbc93998a90/libavcodec/qsvenc.c#L376

I may misunderstand the "configuration" you mentioned. Do you mean checking " QSV_HAVE_VDENC "?