[FFmpeg-devel] [PATCH] Fix mpegtsenc's choking on first H264 start code

Baptiste Coudurier baptiste.coudurier
Fri Sep 10 20:58:31 CEST 2010


On 09/10/2010 08:20 AM, Mike Scheutzow wrote:
> Alexandre Ferrieux wrote:
>> Hi,
>>
>> It turns out that when muxing an H264 bitstream, mpegts_write_packet
>> has a
>> very crude check on AnnexB start codes. Specifically, it wants a 4-byte
>> 00000001, disallowing the 3-byte 000001 which is also valid and occurs on
>> the first NALU. As a consequence, ffmpeg is currently unable to mux H264
>> into TS:
>>
>> [...]
>
> I don't believe your patch complies with the requirements of the H.264
> spec. Annex B.1.2 *requires* the 4-byte start code for an SPS NAL and
> for the first NAL in a bitstream.
>
> You could maybe make the muxer more flexible about the input it accepts
> (Baptiste will decide that), but even then the muxer output must contain
> the extra 0x00 to generate a compliant bitstream.

Im not opposed to that at all.

-- 
Baptiste COUDURIER
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