Re: [Gmerlin-general] bgav_start

[Burkhard P. <pl...@ip...>]

Hi,

august wrote
> when I do bgav_start on two files in my threaded app, I sometimes
> (98% of the time) get this:
>
> [NULL @ 0x7f479b059900]insufficient thread locking around
> avcodec_open/close()
> [track] Error: Starting video decoder for stream 1 failed
>
>
> what does that mean?  do I need to lock around bgav_ calls?

It means that libavcodec has lots of tables as global variables
(for saving memory) but it leaves proper locking to the caller.

There would be 3 solutions (from best to worst):

1. libavcodec does the locking internally

2. gmerlin-avdecoder protects calls to avcodec_open/close()
   with a global mutex. This would be only a partial solution
   because one can e.g. decode with gmerlin-avdecoder and
   encode with libquicktime at the same time, both of them
   would be linked to libavcodec.

3. You make a global lock around calls to bgav_start() and
   bgav_close() and probably bgav_select_track().

As a temporary workaround (because I'm about to leave for a 2 weeks
vacation) you can implement 3. When I'm back I can implement 2.

Burkhard