[FFmpeg-devel] [PATCH] avcodec/cbs_av1: fix parsing delta_frame_id_minus1

[James Almer]

On 12/20/2018 5:45 PM, Mark Thompson wrote:
> On 20/12/2018 15:39, James Almer wrote:
>> delta_frame_id_minus1 is not a single value in the bitstream, and can
>> store values up to 17 bits wide.
>>
>> Fixes parsing files with frame ids.
>>
>> Signed-off-by: James Almer <jamrial at gmail.com>
>> ---
>> See https://code.videolan.org/videolan/dav1d/uploads/a23d47dda3011a8e39ab1ac7c508b220/input.ivf
>>
>>  libavcodec/cbs_av1.h                 | 2 +-
>>  libavcodec/cbs_av1_syntax_template.c | 4 ++--
>>  2 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/libavcodec/cbs_av1.h b/libavcodec/cbs_av1.h
>> index 84622ed189..71ceff9427 100644
>> --- a/libavcodec/cbs_av1.h
>> +++ b/libavcodec/cbs_av1.h
>> @@ -170,7 +170,7 @@ typedef struct AV1RawFrameHeader {
>>      uint8_t last_frame_idx;
>>      uint8_t golden_frame_idx;
>>      int8_t  ref_frame_idx[AV1_REFS_PER_FRAME];
>> -    uint8_t delta_frame_id_minus1;
>> +    uint32_t delta_frame_id_minus1[AV1_REFS_PER_FRAME];
>>  
>>      uint8_t allow_high_precision_mv;
>>      uint8_t is_filter_switchable;
>> diff --git a/libavcodec/cbs_av1_syntax_template.c b/libavcodec/cbs_av1_syntax_template.c
>> index 0da79b615d..48f4fab514 100644
>> --- a/libavcodec/cbs_av1_syntax_template.c
>> +++ b/libavcodec/cbs_av1_syntax_template.c
>> @@ -1323,8 +1323,8 @@ static int FUNC(uncompressed_header)(CodedBitstreamContext *ctx, RWContext *rw,
>>              if (!current->frame_refs_short_signaling)
>>                  fbs(3, ref_frame_idx[i], 1, i);
>>              if (seq->frame_id_numbers_present_flag) {
>> -                fb(seq->delta_frame_id_length_minus_2 + 2,
>> -                   delta_frame_id_minus1);
>> +                fbs(seq->delta_frame_id_length_minus_2 + 2,
>> +                    delta_frame_id_minus1[i], 1, i);
>>              }
>>          }
>>  
>>
> 
> Yep, LGTM.  (I hate the mutable single-syntax-element variables in that spec.)
> 
> Thanks,
> 
> - Mark

Pushed, will backport later. Thanks!