[FFmpeg-devel] [PATCH] avcodec/libaomenc: Extract extradata directly if available

[James Almer]

On 9/12/2020 11:39 AM, Andriy Gelman wrote:
> From: Andriy Gelman <andriy.gelman at gmail.com>
> 
> Currently a bsf is inserted to extract OBU headers which are propagated
> as packet side data. The side data is used in matroska to insert out of
> band extradata.
> 
> Support to fetch extradata directly from av1 was added in commit
> f8d6a1653476662a7b00a1564afe37516adeba1a in libaom. So there is no need
> to insert a bsf if extradata can be fetched.

No, see https://bugs.chromium.org/p/aomedia/issues/detail?id=2208

aom_codec_get_global_headers() has a bug that hasn't been fixed. That's
why i haven't implemented it yet in our wrapper.

> 
> Signed-off-by: Andriy Gelman <andriy.gelman at gmail.com>
> ---
>  libavcodec/libaomenc.c | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/libavcodec/libaomenc.c b/libavcodec/libaomenc.c
> index 2b0581b15a..27ee630382 100644
> --- a/libavcodec/libaomenc.c
> +++ b/libavcodec/libaomenc.c
> @@ -879,6 +879,18 @@ static av_cold int aom_init(AVCodecContext *avctx,
>          return AVERROR(ENOMEM);
>  
>      if (avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
> +        aom_fixed_buf_t *aom_buf;
> +        aom_buf = aom_codec_get_global_headers(&ctx->encoder);
> +        if (aom_buf) {
> +            avctx->extradata = av_mallocz(aom_buf->sz + AV_INPUT_BUFFER_PADDING_SIZE);
> +            memcpy(avctx->extradata, aom_buf->buf, aom_buf->sz);
> +            avctx->extradata_size = aom_buf->sz;
> +            av_free(aom_buf->buf);
> +            av_freep(&aom_buf);
> +        }
> +    }
> +
> +    if (!avctx->extradata && avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
>          const AVBitStreamFilter *filter = av_bsf_get_by_name("extract_extradata");
>          int ret;
>  
> @@ -976,7 +988,7 @@ static int storeframe(AVCodecContext *avctx, struct FrameListData *cx_frame,
>  #endif
>      }
>  
> -    if (avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
> +    if (ctx->bsf) {
>          ret = av_bsf_send_packet(ctx->bsf, pkt);
>          if (ret < 0) {
>              av_log(avctx, AV_LOG_ERROR, "extract_extradata filter "
>