#24 Extract audio from mp4 video

[Wolfgang Klein]

I remember that it was possible to right click an mp4 video and select "convert to mp3" from pacpl's context menu in KDE4. Now I am using KDE5 (KDE neon) and pacpl does not do this any more.

Execution on the command line shows this error message;

~/download$ pacpl --to mp3  --verbose video.mp4 

Perl Audio Converter - 5.0.1

Konvertierung: video.mp4 -> mp3
 *********** Ahead Software MPEG-4 AAC Decoder V2.8.8 ******************

 Copyright 2002-2004: Ahead Software AG
 http://www.audiocoding.com
 bug tracking: https://sourceforge.net/p/faac/bugs/
 Floating point version

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License.

 **************************************************************************

**** MP4 header ****
Brand:                  mp42(version 0)
Compatible brands:      isom
*track media type: 'vide': unsupported, skipping
*track media type: 'soun': OK
Modification Time:              Wed Oct 24 23:09:55 2018
Samplerate:             48000
Total samples:          87937024
Total channels:         2
Bits per sample:        16
Buffer size:            65535
Max bitrate:            115500
Average bitrate:        93468
Samples per frame:      0
Frames:                 85876
ASC size:               4
Duration:               1832.0 sec
Data offset/size:       ed4f8/0
********************
parse error: atom 'udta' not found
invalid atom size 1 @e54f5
/home/wolfgang/download/video.mp4 file info:

LC AAC  1832.021 secs, 2 ch, 48000 Hz

  ---------------------
 | Config:  2 Ch       |
  ---------------------
 | Ch |    Position    |
  ---------------------
 | 00 | Left front     |
 | 01 | Right front    |
  ---------------------

Floating point exceptionng/download/video.mp4.

Dekodierung ist fehlgeschlagen mit dem Status: /home/wolfgang/download/video.mp4: try with --verbose

Total files converted: 0, failed: 1

This is just an example, the error is the same, no matter the source of the video. Am I missing an important package on my system?

[Wolfgang Klein]

**Supplement: **

I think I found the bug. The program seems to insist to use avconv, but that package is not used any more in Ubuntu > 14.x:

pacpl --decoder mp4

Perl Audio Converter - 5.0.1

decoders for: mp4

avconv -> 
faad -> installed (default)
ffmpeg -> installed
mplayer -> installed

If I force pacpl to use ffmpeg, all goes well:

pacpl --to mp3 --encoder ffmpeg --decoder ffmpeg video.mp4 

Perl Audio Converter - 5.0.1

Konvertierung: video.mp4 -> mp3

Total files converted: 1, failed: 0

So, how do I tell papcl to use ffmpeg as standard encode/decoder in its config file?