[FFmpeg-devel] [PATCH] Improved analysis of h264 bitstreams with no B frames

Mike Scheutzow mjs973 at optonline.net
Sun May 8 13:53:54 CEST 2011

Michael Niedermayer wrote:
> On Sat, May 07, 2011 at 12:03:48PM -0400, Mike Scheutzow wrote:
>> The sps.constraint_set0_flag indicates that the bitstream is baseline profile,
>> which means the stream has no B-pictures.  This patch fixes trac0088.
> sps.constraint_set_flags&1 indicates no B frames
> but no B frames does not implicate low_delay=1.
It seems to me that's exactly what the other code in FFmpeg assumes.

FFmpeg currently uses low_delay=0 to set has_b_frames=1 which then 
rejects PTS==DTS for I and P pictures.

Which assumption do you prefer to change?

Mike Scheutzow

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