[FFmpeg-devel] [PATCH 1/3] cbs_av1: Fix header writing when already aligned

[James Almer]

On 11/5/2018 11:12 AM, Mark Thompson wrote:
> On 05/11/18 13:14, James Almer wrote:
>> On 11/4/2018 9:10 PM, Mark Thompson wrote:
>>> ---
>>> Previously it lost the trailing bits byte but did include it in the OBU size, completely breaking the stream.
>>>
>>>
>>>  libavcodec/cbs_av1.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c
>>> index 9bac9dde09..1c49d90f51 100644
>>> --- a/libavcodec/cbs_av1.c
>>> +++ b/libavcodec/cbs_av1.c
>>> @@ -1179,7 +1179,7 @@ static int cbs_av1_write_obu(CodedBitstreamContext *ctx,
>>>          if (err < 0)
>>>              return err;
>>>          end_pos = put_bits_count(pbc);
>>> -        obu->obu_size = (end_pos - start_pos + 7) / 8;
>>> +        obu->obu_size = header_size = (end_pos - start_pos + 7) / 8;
>>>      } else {
>>>          // Empty OBU.
>>>          obu->obu_size = 0;
>>>
>>
>> What samples was this breaking? The few i tried have matching checksum
>> after an av1_metadata passthrough.
> 
> Your s6Nh.ivf file with redundant headers requires it.  (I spent quite a while banging my head against that one, because the write trace showed exactly the right thing but then reading it back was messed up.)
> 
> - Mark

Right, it was a dep for patch 2.

LGTM then.