demux_lavf: workaround minor ffmpeg memory leak

The sequence of avcodec_alloc_context3() / avcodec_copy_context() /
avcodec_close() / av_free() leaks some memory. So don't copy the context
and use it directly.

Originally avcodec_copy_context() was used to guarantee that libavformat
can't update the fields of the context during demuxing in order to make
things a little more robust, but it's not strictly needed, and
ffmpeg/ffplay don't do this anyway. Still might make the situation worse
should we move demuxing into a separate thread, though.

0 files changed, 0 insertions, 0 deletions