[Libav-user] Simple packet-by-packet copy does not work for h264+mp4

Andrey Utkin andrey.krieger.utkin at gmail.com
Thu Mar 1 16:47:56 CET 2012

2012/3/1 ALESSANDRO PAGANELLI <83670 at studenti.unimore.it>:
> I tried to use avformat_find_stream_info() (I did not use it before) but the
> program still fails, this time due to segmentation fault because
> g_inputFormatContext->streams[i]->info is NULL.
> Maybe I did something wrong when i produced the original mp4 file with VLC.

Fail you got may be caused by wrong invocation of the function, but it
is right way to go. I encourage you to use this function. The same
about avcodec_copy_context() - it is right to use it, but not to copy
everything manually, as you do now.

You can take my remux app as an example. But watch out - it is not
general-purposed, but just for exact use case.

Also there's very simple skeleton of remultiplexing:

Andrey Utkin

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