[FFmpeg-devel] [PATCH v3] avcodec/h264_parse: retry decoding SPS with complete NAL

[James Almer]

On 8/22/2019 5:58 PM, Jun Li wrote:
> Fix #6591
> The content has no rbsp_stop_one_bit for ending the SPS, that
> causes the decoding SPS failure, results decoding frame failure as well.
> 
> The patch is just adding a retry with complete NALU, copied from the retry in decode_nal_unit()
> ---
>  libavcodec/h264_parse.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/libavcodec/h264_parse.c b/libavcodec/h264_parse.c
> index ac31f54e07..baf8246cdc 100644
> --- a/libavcodec/h264_parse.c
> +++ b/libavcodec/h264_parse.c
> @@ -374,11 +374,23 @@ static int decode_extradata_ps(const uint8_t *data, int size, H264ParamSets *ps,
>      for (i = 0; i < pkt.nb_nals; i++) {
>          H2645NAL *nal = &pkt.nals[i];
>          switch (nal->type) {
> -        case H264_NAL_SPS:
> -            ret = ff_h264_decode_seq_parameter_set(&nal->gb, logctx, ps, 0);
> -            if (ret < 0)
> -                goto fail;
> +        case H264_NAL_SPS: {
> +            GetBitContext tmp_gb = nal->gb;
> +            ret = ff_h264_decode_seq_parameter_set(&tmp_gb, logctx, ps, 0);
> +            if (ret < 0) {
> +                av_log(logctx, AV_LOG_DEBUG,
> +                      "SPS decoding failure, trying again with the complete NAL\n");
> +                init_get_bits8(&tmp_gb, nal->raw_data + 1, nal->raw_size - 1);
> +                ret = ff_h264_decode_seq_parameter_set(&tmp_gb, logctx, ps, 0);
> +                if (ret >= 0)
> +                    break;
> +
> +                ret = ff_h264_decode_seq_parameter_set(&nal->gb, logctx, ps, 1);
> +                if (ret < 0)
> +                    goto fail;
> +            }
>              break;
> +        }
>          case H264_NAL_PPS:
>              ret = ff_h264_decode_picture_parameter_set(&nal->gb, logctx, ps,
>                                                         nal->size_bits);

Removed one level of indentation and pushed. Thanks.