[Libav-user] Re-encoding a time interval in existing video

[Andrey Utkin]

I've solved my issue.
Shortly:
I remuxed MP4 file to Annex B format with -bsf h264_mp4toannexb.
Then, concatenating pieces of original (Annex B) file, and pieces
filtered/transcoded by ffmpeg succeeds.
As i have guess, Annex B format does not depend on on global headers
aka extradata, and all the decoding information lies in the frames.
Please correct me if i am not right.

-- 
Andrey Utkin