[FFmpeg-devel] [PATCH] avfilter/src_movie: dr support

[James Almer]

> From e1dc1a00ac327d450c33586269cb19230f433405 Mon Sep 17 00:00:00 2001
> From: Paul B Mahol <onemda at gmail.com>
> Date: Mon, 15 May 2023 21:54:25 +0200
> Subject: [PATCH 2/3] avfilter/src_movie: dr support
> 
> Signed-off-by: Paul B Mahol <onemda at gmail.com>
> ---
>  libavfilter/src_movie.c | 40 ++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 38 insertions(+), 2 deletions(-)
> 
> diff --git a/libavfilter/src_movie.c b/libavfilter/src_movie.c
> index a7d7c188e6..bc0b8b7ac6 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
>   */
>  
> @@ -158,6 +157,39 @@ 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 h = frame->height;
> +    int w = frame->width;
> +    AVFrame *new;
> +
> +    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, frame->width, frame->height);

You're not using the values from w and h at all. You need to allocate 
the frame buffers with them, since the point of this is padding the 
buffers based on the needs of each decoder. The AVFrame however must 
retain the non altered values.

> +        break;
> +    case AVMEDIA_TYPE_AUDIO:
> +        new = ff_default_get_audio_buffer(outlink, frame->nb_samples);
> +        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;
> +
> +    return 0;
> +}
> +
>  static int open_stream(AVFilterContext *ctx, MovieStream *st, int dec_threads)
>  {
>      const AVCodec *codec;
> @@ -173,6 +205,8 @@ 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;
> @@ -480,8 +514,10 @@ 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
>