[FFmpeg-devel] [PATCH 2/2] lavc/videotoolboxenc: enable low-latency mode for HEVC

[mypopy at gmail.com]

On Fri, Sep 1, 2023 at 2:13 AM Zhao Zhili <quinkblack at foxmail.com> wrote:
>
>
> > From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of Jun Zhao
> > Sent: 2023年8月31日 22:50
> > To: ffmpeg-devel at ffmpeg.org
> > Cc: Jun Zhao <barryjzhao at tencent.com>; Jun Zhao <mypopydev at gmail.com>
> > Subject: [FFmpeg-devel] [PATCH 2/2] lavc/videotoolboxenc: enable low-latency mode for HEVC
> >
> > Enable the HEVC encoder that supports low-latency mode.
> >
> > Signed-off-by: Jun Zhao <barryjzhao at tencent.com>
> > ---
> >  libavcodec/videotoolboxenc.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/libavcodec/videotoolboxenc.c b/libavcodec/videotoolboxenc.c
> > index 8e493c4f7a..bfc03787a0 100644
> > --- a/libavcodec/videotoolboxenc.c
> > +++ b/libavcodec/videotoolboxenc.c
> > @@ -1568,7 +1568,8 @@ static int vtenc_configure_encoder(AVCodecContext *avctx)
> >  #endif
> >
> >      // low-latency mode: eliminate frame reordering, follow a one-in-one-out encoding mode
> > -    if ((avctx->flags & AV_CODEC_FLAG_LOW_DELAY) && avctx->codec_id == AV_CODEC_ID_H264) {
> > +    if ((avctx->flags & AV_CODEC_FLAG_LOW_DELAY) &&
> > +        (avctx->codec_id == AV_CODEC_ID_H264 || avctx->codec_id == AV_CODEC_ID_HEVC)) {
>
> How about just remove the codec_id check?
> Is there any unwelcome side effects for encoders other than H264/HEVC?

1. One reason is that there are now other encoders available, such as
prores_videotoolbox.

2. It may be more appropriate to use a strictly qualified check
instead of an open condition.