> From: myp...@gmail.com <myp...@gmail.com> > Sent: Monday, April 13, 2020 15:43 > To: FFmpeg development discussions and patches <ffmpeg- > de...@ffmpeg.org> > Cc: Fu, Linjie <linjie...@intel.com> > Subject: Re: [FFmpeg-devel] [PATCH] lavc/vaapi_encode_h265: add > low_delay_b option for HEVC > > On Mon, Apr 13, 2020 at 12:39 PM Linjie Fu <linjie...@intel.com> wrote: > > > > Low delay B-frame is supported on ICL+ platform. > > > > For low power encoding, low_delay_b should be enabled by default. > > > > Low delay B: > > <http://what-when-how.com/Tutorial/topic-397pct9eq3/High-Efficiency- > Video-Coding-HEVC-288.html> > > > > There is an on-going work in libva and media-driver to add querys > > support for low delay b, would add it once it's ready: > > https://github.com/intel/libva/pull/220 > > https://github.com/intel/libva/pull/364 > > https://github.com/intel/media-driver/issues/721 > > > > Signed-off-by: Linjie Fu <linjie...@intel.com> > > --- > > doc/encoders.texi | 8 ++++++++ > > libavcodec/vaapi_encode_h265.c | 19 +++++++++++++++++-- > > 2 files changed, 25 insertions(+), 2 deletions(-) > > > > diff --git a/doc/encoders.texi b/doc/encoders.texi > > index e23b6b3..b0812be 100644 > > --- a/doc/encoders.texi > > +++ b/doc/encoders.texi > > @@ -3089,6 +3089,14 @@ Some combination of the following values: > > Include HDR metadata if the input frames have it > > (@emph{mastering_display_colour_volume} and > @emph{content_light_level} > > messages). > > + > > +@item low_delay_b > > +Use low delay B-frames instead of P frames. Reordering of pictures is > > +not allowed. The first picture is encoded as an I picture and subsequent > > +pictures are encoded as B pictures. Moreover, since past B pictures are > > +used for prediction, a low coding delay but with higher coding efficiency > > +(because of bi-prediction) is achieved. > > + > > @end table > > > > @end table > > diff --git a/libavcodec/vaapi_encode_h265.c > b/libavcodec/vaapi_encode_h265.c > > index 97dc5a7..cd48545 100644 > > --- a/libavcodec/vaapi_encode_h265.c > > +++ b/libavcodec/vaapi_encode_h265.c > > @@ -62,6 +62,7 @@ typedef struct VAAPIEncodeH265Context { > > int tier; > > int level; > > int sei; > > + int low_delay_b; > > > > // Derived settings. > > int fixed_qp_idr; > > @@ -894,6 +895,9 @@ static int > vaapi_encode_h265_init_slice_params(AVCodecContext *avctx, > > > > sh->slice_type = hpic->slice_type; > > > > + if (sh->slice_type == HEVC_SLICE_P && priv->low_delay_b) > > + sh->slice_type = HEVC_SLICE_B; > Add a trace or info message in this, it's will help to reduce the > sudden surprises,
Yes, considered this and the trace/info message for low_delay_b change was added in vaapi_encode_h265_init() as a AV_LOG_VERBOSE Information, so I didn't prompt a debug information for each slice. > the other question is, if enable the low_delay_b in > ICL- platform, what is the result of this? Possibly leads to encoding failure. And that's why a query support is necessary for this option/feature on ICL-. While replying this mail, I noticed this patch is insufficient. Will update a new one, sorry for the noise. - Linjie _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
