Re: [FFmpeg-devel] [PATCH] avfilter/src_movie: activate & dr

[Paul B Mahol <onemda@gmail.com>]

On Thu, May 18, 2023 at 7:31 PM James Almer <jamrial@gmail.com> wrote:

> On 5/18/2023 7:22 AM, Paul B Mahol wrote:
> > From af73b69a0be9033fddf222b6e9ac60799de85691 Mon Sep 17 00:00:00 2001
> > From: Paul B Mahol <onemda@gmail.com>
> > Date: Mon, 15 May 2023 21:54:25 +0200
> > Subject: [PATCH 26/27] avfilter/src_movie: dr support
> >
> > Signed-off-by: Paul B Mahol <onemda@gmail.com>
> > ---
> >  libavfilter/src_movie.c | 44 +++++++++++++++++++++++++++++++++++++++--
> >  1 file changed, 42 insertions(+), 2 deletions(-)
> >
> > diff --git a/libavfilter/src_movie.c b/libavfilter/src_movie.c
> > index 5937613d13..a2ecc5a625 100644
> > --- a/libavfilter/src_movie.c
> > +++ b/libavfilter/src_movie.c
> > @@ -23,7 +23,6 @@
> >   * @file
> >   * movie video source
> >   *
> > - * @todo use direct rendering (no allocation of a new frame)
> >   * @todo support a PTS correction mechanism
> >   */
> >
> > @@ -156,6 +155,43 @@ static AVStream *find_stream(void *log,
> AVFormatContext *avf, const char *spec)
> >      return found;
> >  }
> >
> > +static int get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
> > +{
> > +    int linesize_align[AV_NUM_DATA_POINTERS];
> > +    AVFilterLink *outlink = frame->opaque;
> > +    int w, h, ow, oh;
> > +    AVFrame *new;
> > +
> > +    h = oh = frame->height;
> > +    w = ow = frame->width;
> > +
> > +    if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1))
> > +        return avcodec_default_get_buffer2(avctx, frame, flags);
> > +
> > +    switch (avctx->codec_type) {
> > +    case AVMEDIA_TYPE_VIDEO:
> > +        avcodec_align_dimensions2(avctx, &w, &h, linesize_align);
> > +        new = ff_default_get_video_buffer(outlink, w, h);
> > +        break;
> > +    case AVMEDIA_TYPE_AUDIO:
> > +        new = ff_default_get_audio_buffer(outlink, frame->nb_samples);
>
> I wonder, are these two functions thread safe?
> AVCodecContext.get_buffer2() no longer supports non-thread safe
> callbacks, and these seem to allocate and replace the pool inside
> outlink as required. If called from more than one thread with different
> frame parameters, wouldn't there be a race?
>

I encountered no issues in my testing.


>
> > +        break;
> > +    default:
> > +        return -1;
> > +    }
> > +
> > +    av_frame_copy_props(new, frame);
> > +    av_frame_unref(frame);
> > +    av_frame_move_ref(frame, new);
> > +    av_frame_free(&new);
> > +
> > +    frame->opaque = outlink;
> > +    frame->width  = ow;
> > +    frame->height = oh;
> > +
> > +    return 0;
> > +}
> > +
> >  static int open_stream(AVFilterContext *ctx, MovieStream *st, int
> dec_threads)
> >  {
> >      const AVCodec *codec;
> > @@ -171,6 +207,8 @@ static int open_stream(AVFilterContext *ctx,
> MovieStream *st, int dec_threads)
> >      if (!st->codec_ctx)
> >          return AVERROR(ENOMEM);
> >
> > +    st->codec_ctx->flags |= AV_CODEC_FLAG_COPY_OPAQUE;
> > +    st->codec_ctx->get_buffer2 = get_buffer;
> >      ret = avcodec_parameters_to_context(st->codec_ctx,
> st->st->codecpar);
> >      if (ret < 0)
> >          return ret;
> > @@ -479,8 +517,10 @@ static int movie_decode_packet(AVFilterContext *ctx)
> >      /* send the packet to its decoder, if any */
> >      pkt_out_id = pkt.stream_index > movie->max_stream_index ? -1 :
> >                   movie->out_index[pkt.stream_index];
> > -    if (pkt_out_id >= 0)
> > +    if (pkt_out_id >= 0) {
> > +        pkt.opaque = ctx->outputs[pkt_out_id];
> >          ret = avcodec_send_packet(movie->st[pkt_out_id].codec_ctx,
> &pkt);
> > +    }
> >      av_packet_unref(&pkt);
> >
> >      return ret;
> > --
> > 2.39.1
> >
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
>
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".