[Libav-user] Decoding audio: ffmpeg examples

Angelo Haller libav-user at szanni.org
Mon Jan 14 22:05:06 CET 2013


I've been looking at the examples on how to use ffmpeg
and I found a few issues.

Fist of all there seems to be a memory leak in
doc/examples/demuxing.c (valgrind certainly tells me that).
Freeing the AVPacket seems to resolve that issue (see the patch
attached). Hope I didn't miss anything here.

Another thing I noticed is that the demuxer example does not call
avcodec_get_frame_defaults() on the frame that it is reusing. Or
does that not really matter? The docs state that you "should"
and not "must".

Then when looking at doc/examples/decoding_encoding.c I noticed
that there is no extra call to avcodec_decode_audio4() when
decoding audio. The docs state that some decoders cache frames.
Is that really true for audio decoding? Line 601 says something about
P and I frames being delayed in the MPEG video decoder...
If so, then I think that some of the audio could go missing in this

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