[FFmpeg-devel] [PATCH 2/2] avcodec/cbs_h2645: create a reference to the existing buffer when decomposing slice units

[Mark Thompson]

On 28/04/18 00:50, James Almer wrote:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>  libavcodec/cbs_h2645.c | 18 ++++--------------
>  1 file changed, 4 insertions(+), 14 deletions(-)
> 
> diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
> index 5585831cf6..5e5598f377 100644
> --- a/libavcodec/cbs_h2645.c
> +++ b/libavcodec/cbs_h2645.c
> @@ -776,15 +776,10 @@ static int cbs_h264_read_nal_unit(CodedBitstreamContext *ctx,
>              }
>  
>              slice->data_size = len - pos / 8;
> -            slice->data_ref  = av_buffer_alloc(slice->data_size +
> -                                               AV_INPUT_BUFFER_PADDING_SIZE);
> +            slice->data_ref  = av_buffer_ref(unit->data_ref);
>              if (!slice->data_ref)
>                  return AVERROR(ENOMEM);
> -            slice->data = slice->data_ref->data;
> -            memcpy(slice->data,
> -                   unit->data + pos / 8, slice->data_size);
> -            memset(slice->data + slice->data_size, 0,
> -                   AV_INPUT_BUFFER_PADDING_SIZE);
> +            slice->data = unit->data + pos / 8;
>              slice->data_bit_start = pos % 8;
>          }
>          break;
> @@ -946,15 +941,10 @@ static int cbs_h265_read_nal_unit(CodedBitstreamContext *ctx,
>              }
>  
>              slice->data_size = len - pos / 8;
> -            slice->data_ref  = av_buffer_alloc(slice->data_size +
> -                                               AV_INPUT_BUFFER_PADDING_SIZE);
> +            slice->data_ref  = av_buffer_ref(unit->data_ref);
>              if (!slice->data_ref)
>                  return AVERROR(ENOMEM);
> -            slice->data = slice->data_ref->data;
> -            memcpy(slice->data,
> -                   unit->data + pos / 8, slice->data_size);
> -            memset(slice->data + slice->data_size, 0,
> -                   AV_INPUT_BUFFER_PADDING_SIZE);
> +            slice->data = unit->data + pos / 8;
>              slice->data_bit_start = pos % 8;
>          }
>          break;
> 

Also looks good.

(We could probably avoid duplicating this code, too, though that's orthogonal to the patch.)

Thanks,

- Mark