How do I setup Codec manually?

[forceassaulter]

I need to stream the video in mpeg format from buffer, hence the buffer is too short for FFMPEG to detect codec automatically, how do I setup codec manually?

The error:
probed stream 0 failed start time for stream 0 is not set in estimate_timings_from_pts Could not find codec parameters for stream 0 (Video: none, none): unknown codec Consider increasing the value for the 'analyzeduration' and 'probesize' options

[kkangshen]

I encountered the same problem when using pyav parsing, and I don't know how to solve it