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I'm trying to merge two cd-s into 1 file and also boost sound volume 200%, I tried this using avconv tool, but I only got cd1 and without an boost in sound:

nohup avconv -i cd1.avi -i cd2.avi -vcodec libx264 -acodec libvo_aacenc -r 30000/1001 -vol 512 merged.mp4

I used same syntax as for ffmpeg, any ideas why it didn't work? I can't find documentation for -vol for avconv. and also info about merging files is scarce.

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Please show your ffmpeg command and the complete ffmpeg console output. – LordNeckbeard Jun 23 '13 at 1:32
@LordNeckbeard I don't have ffmpeg anymore, it was replaced by avconv on ubuntu. So I figured both tools have same devs and they are same software essentially, I used ffmpeg flags. – Sandro Dzneladze Jun 23 '13 at 5:03
Both tools do not have the same developers and there are differences. See Who can tell me the difference and relation between ffmpeg, libav, and avconv? – LordNeckbeard Jun 23 '13 at 19:24

avconv does not support concatentation (yet, patches welcome). The ways to work around this are e.g.

  • use mplayer(2) with -vo yuv4mpeg to decode your two video into a pipe, make avconv read from this pipe.

  • encode the two videos separately, then use mkvmerge to merge them.

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