[FFmpeg-devel] [PATCH 2/4] lavd: make lavfi device export the metadata up to the AVFrame.

[Stefano Sabatini]

On date Wednesday 2012-10-10 00:55:11 +0200, Clément Bœsch encoded:
> TODO: lavc minor bump?
> ---
>  libavcodec/avcodec.h | 1 +
>  libavcodec/utils.c   | 7 +++++++
>  libavdevice/lavfi.c  | 9 +++++++++
>  3 files changed, 17 insertions(+)
> 
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 6c4b630..ca7cd75 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -1008,6 +1008,7 @@ typedef struct AVPacket {
>  } AVPacket;
>  #define AV_PKT_FLAG_KEY     0x0001 ///< The packet contains a keyframe
>  #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
> +#define AV_PKT_FLAG_META    0x0100 ///< The packet priv points to metadata

May be acceptable, but I leave this to people with more packet API
insight.

Also I'm not sure about the name, "META" (meta packet??) doesn't tell
much, "METADATA_IN_PRIV" or "PRIV_METADATA" may be more descriptive.

Also I'd specify something in the docs along the lines:
Metadata is stored in the demuxer, and is not preserved at the next
call of av_read_frame().

Also missing: API changhes entry for the new symbol.

>  enum AVSideDataParamChangeFlags {
>      AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT  = 0x0001,
> diff --git a/libavcodec/utils.c b/libavcodec/utils.c
> index 036cbdf..85b42e5 100644
> --- a/libavcodec/utils.c
> +++ b/libavcodec/utils.c
> @@ -1590,6 +1590,9 @@ int attribute_align_arg avcodec_decode_video2(AVCodecContext *avctx, AVFrame *pi
>  
>          emms_c(); //needed to avoid an emms_c() call before every return;
>  
> +        if (avctx->pkt->flags & AV_PKT_FLAG_META)
> +            picture->metadata = avctx->pkt->priv;
> +
>          avctx->pkt = NULL;
>          if (did_split) {
>              ff_packet_free_side_data(&tmp);
> @@ -1713,6 +1716,10 @@ int attribute_align_arg avcodec_decode_audio4(AVCodecContext *avctx,
>              av_log(avctx, AV_LOG_DEBUG, "skip %d samples due to side data\n",
>                     avctx->internal->skip_samples);
>          }
> +
> +        if (avctx->pkt->flags & AV_PKT_FLAG_META)
> +            frame->metadata = avctx->pkt->priv;
> +
>          if (avctx->internal->skip_samples) {
>              if(frame->nb_samples <= avctx->internal->skip_samples){
>                  *got_frame_ptr = 0;
> diff --git a/libavdevice/lavfi.c b/libavdevice/lavfi.c
> index 860c055..6e76b5f 100644
> --- a/libavdevice/lavfi.c
> +++ b/libavdevice/lavfi.c
> @@ -48,6 +48,7 @@ typedef struct {
>      int *sink_stream_map;
>      int *sink_eof;
>      int *stream_sink_map;
> +    AVDictionary *metadata; ///< metadata of the current packet
>  } LavfiContext;
>  
>  static int *create_all_formats(int n)
> @@ -76,6 +77,7 @@ av_cold static int lavfi_read_close(AVFormatContext *avctx)
>      av_freep(&lavfi->sink_eof);
>      av_freep(&lavfi->stream_sink_map);
>      av_freep(&lavfi->sinks);
> +    av_dict_free(&lavfi->metadata);
>      avfilter_graph_free(&lavfi->graph);
>  
>      return 0;
> @@ -336,6 +338,13 @@ static int lavfi_read_packet(AVFormatContext *avctx, AVPacket *pkt)
>          memcpy(pkt->data, ref->data[0], size);
>      }
>  
> +    if (ref->metadata) {
> +        av_dict_free(&lavfi->metadata);
> +        av_dict_copy(&lavfi->metadata, ref->metadata, 0);
> +        pkt->flags |= AV_PKT_FLAG_META;
> +        pkt->priv = lavfi->metadata;
> +    }
> +
>      pkt->stream_index = stream_idx;
>      pkt->pts = ref->pts;
>      pkt->pos = ref->pos;
> -- 
> 1.7.12.2

LGTM otherwise.
-- 
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