id,summary,reporter,owner,description,type,status,priority,component,version,resolution,keywords,cc,blockedby,blocking,reproduced,analyzed
1731,libavformat muxers destroy initial timestamp offsets,saste,,"Many muxers in libavformat (tested: avi, flv) destory the initial offset.
This is meant as a feature, but has the effect that remuxing a file will destroy the original timestamp information. This is especially annoying in case streams from different sources need to be synched.

How to reproduce:
{{{
ffmpeg -f lavfi -i ""aevalsrc=sin(2*PI*400*t)::d=5,asetpts=PTS+10/TB"" -y out.flv
}}}

then check the packet timestamps with ffprobe -show_packets out.flv.

A possible workaround:
{{{
ffmpeg -f lavfi -i ""aevalsrc=sin(2*PI*400*t)::d=5,asetpts=PTS+10/TB,aresample=min_comp=0.001:min_hard_comp=0.0010"" -y out.flv
}}}

(with video the problem can't be easily worked around).

The behavior with respect to the initial offset could be made configurable through some options.
",defect,new,normal,avformat,unspecified,,muxer timestamp flv avi,,,,0,0