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I'm getting a message, that it cannot resample 6 channels into 2 channel audio. This is the command i'm using to convert into h.264+aac:

avconv -i /var/movies/ -strict experimental -acodec aac -ac 2 -ab 128k -ar 44100 -y -c:v libx264 -qscale 1 -s 640x480 -g 25 -r 25 /path/to

Exact message:

Resampling output channel count must be 1 or 2 for mono input; 1, 2 or 6 for stereo input; or N for N channel input.
Can not resample 6 channels @ 48000 Hz to 2 channels @ 44100 Hz

I have tried so many configurations, have tired experimenting.

Any video guru out there? Some tip would be awesome.


Here is avconv info:

avconv version 0.8.6-4:0.8.6-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav developers
  built on Apr  2 2013 17:02:36 with gcc 4.6.3
share|improve this question
The error message indicates "or N for N channel input.", which suggests that if you have 6 input channels, you can only resample to 6 output channels. Maybe you need a different operation to downsample? – Darth Android May 20 '13 at 15:53
What options do i have in this situation? – Somebody May 20 '13 at 16:07
This suggests that downmixing in this fashion should work, all else being equal. Possibly a dumb question, but: have you tried first downsampling from 48KHz to 44.1KHz, and then downmixing to stereo from there? – Aaron Miller May 20 '13 at 16:55

Get a newer version that has libavresample, i.e. Libav 9 or git master.

share|improve this answer
Does Libav have a proper guide for compilation under Linux, or any static builds? If so, it'd be appreciated if you could link to that here. Thanks! – slhck May 20 '13 at 19:40
There are static linux 64bit builds at . Don't know of any step by step compilation guide for Libav, but it's mostly just ./configure and make / make install. There are some additional notes at . – Anton Khirnov May 23 '13 at 7:32

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