[FFmpeg-devel] [PATCH 19/31] vp9_metadata: Avoid allocations and copies of packet structures

[Mark Thompson]

On 20/06/2019 00:45, Andreas Rheinhardt wrote:
> This commit changes vp9_metadata to (a) use ff_bsf_get_packet_ref
> instead of ff_bsf_get_packet (thereby avoiding one malloc and free per
> filtered packet) and (b) to use only one packet structure at all,
> thereby avoiding a call to av_packet_copy_props.
> 
> (b) has been made possible by the recent changes to ff_cbs_write_packet.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
> ---
>  libavcodec/vp9_metadata_bsf.c | 16 +++++-----------
>  1 file changed, 5 insertions(+), 11 deletions(-)
> 
> diff --git a/libavcodec/vp9_metadata_bsf.c b/libavcodec/vp9_metadata_bsf.c
> index b79f08af6c..1bde1b96aa 100644
> --- a/libavcodec/vp9_metadata_bsf.c
> +++ b/libavcodec/vp9_metadata_bsf.c
> @@ -37,18 +37,17 @@ typedef struct VP9MetadataContext {
>  } VP9MetadataContext;
>  
>  
> -static int vp9_metadata_filter(AVBSFContext *bsf, AVPacket *out)
> +static int vp9_metadata_filter(AVBSFContext *bsf, AVPacket *pkt)
>  {
>      VP9MetadataContext *ctx = bsf->priv_data;
> -    AVPacket *in = NULL;
>      CodedBitstreamFragment *frag = &ctx->fragment;
>      int err, i;
>  
> -    err = ff_bsf_get_packet(bsf, &in);
> +    err = ff_bsf_get_packet_ref(bsf, pkt);
>      if (err < 0)
>          return err;
>  
> -    err = ff_cbs_read_packet(ctx->cbc, frag, in);
> +    err = ff_cbs_read_packet(ctx->cbc, frag, pkt);
>      if (err < 0) {
>          av_log(bsf, AV_LOG_ERROR, "Failed to read packet.\n");
>          goto fail;
> @@ -74,23 +73,18 @@ static int vp9_metadata_filter(AVBSFContext *bsf, AVPacket *out)
>          }
>      }
>  
> -    err = ff_cbs_write_packet(ctx->cbc, out, frag);
> +    err = ff_cbs_write_packet(ctx->cbc, pkt, frag);
>      if (err < 0) {
>          av_log(bsf, AV_LOG_ERROR, "Failed to write packet.\n");
>          goto fail;
>      }
>  
> -    err = av_packet_copy_props(out, in);
> -    if (err < 0)
> -        goto fail;
> -
>      err = 0;
>  fail:
>      ff_cbs_fragment_reset(ctx->cbc, frag);
>  
>      if (err < 0)
> -        av_packet_unref(out);
> -    av_packet_free(&in);
> +        av_packet_unref(pkt);
>  
>      return err;
>  }
> 

13-19 LGTM, applied.

Thanks,

- Mark