[FFmpeg-trac] #420(undetermined:new): Sound fragments after seeking

FFmpeg trac at avcodec.org
Fri Aug 26 12:42:25 CEST 2011


#420: Sound fragments after seeking
--------------------------+--------------------------
 Reporter:  kaptnole      |        Type:  defect
   Status:  new           |    Priority:  important
Component:  undetermined  |     Version:  unspecified
 Keywords:                |  Blocked By:
 Blocking:                |  Reproduced:  1
 Analyzed:  1             |
--------------------------+--------------------------
 While trying to use FFmpeg libs as a developer I found the following:

 When decoding sound from some compressed audio formats and doing a seek,
 the first decoded packet after seeking is buggy.

 I had this with some mp4 files with aac audio codec and some wmv files
 with wma audio codec.
 Looks like some leftovers from internal buffers - but I am using
 'avcodec_flush_buffers'!
 That of course leads to nasty sound noise/clicks.

 See attached sourcecode.
 Basically it shows the first few bytes of the first decoded sound packet
 then seeks back and shows the first packets decoding again.
 If you use it with some wmv or mp4 file with sound you should see see
 effect that both outputs at 0 are different but should be equal.
 Just make sure the sound is not only silence at the first 10 packets.

 Or am I missing some other flush...whatever function here?

 I am developing under windows using the actual ffmpeg git version.
 Confirmed for 32 and 64 bit version, self compiled and downloaded
 autobuilds.

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/420>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker


More information about the FFmpeg-trac mailing list