[FFmpeg-devel] [PATCH] qsvenc_hevc: Enable look ahead with ExtBRC

[Xiang, Haihao]

On Sun, 2021-12-19 at 23:55 +0800, Zhong Li wrote:
> Xiang, Haihao <haihao.xiang at intel.com> 于2021年12月6日周一 11:09写道：
> > > --- a/libavcodec/qsvenc_hevc.c
> > > +++ b/libavcodec/qsvenc_hevc.c
> > > @@ -248,6 +248,7 @@ static const AVOption options[] = {
> > >      { "tile_rows",  "Number of rows for tiled
> > > encoding",      OFFSET(qsv.tile_rows),    AV_OPT_TYPE_INT, { .i64 = 0 },
> > > 0,
> > > UINT16_MAX, VE },
> > >      { "recovery_point_sei", "Insert recovery point SEI
> > > messages",       OFFSET(qsv.recovery_point_sei),      AV_OPT_TYPE_INT, {
> > > .i64
> > > = -1 },               -1,          1, VE },
> > >      { "aud", "Insert the Access Unit Delimiter NAL", OFFSET(qsv.aud),
> > > AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, VE},
> > > +    { "look_ahead_depth", "Depth of look ahead in number frames",
> > > OFFSET(qsv.look_ahead_depth), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 100, VE },
> > > 
> > >      { NULL },
> > >  };
> > 
> > Any comment for this patch ? Could someone help to merge this patch if no
> > objection ?
> 
> How to verify this function? is it depended on a special version of
> MSDK && vaapi-driver?
> I tried to enable extbrc and disable/enable look_ahead_depth (set to
> zero/20) for hevc_qsv but found there are no difference of the encoded
> files.

AFAIK this function depends on your MSDK runtime. There is no impact when user 
turns on this option but the MSDK runtime doesn't support it. 

Thanks
Haihao