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I'm trying to use the Firefox Add-On Downloadhelper to download and convert this 'video' of Einstein: in order to have only its audio. Unfortunately the conversion fails and I have the following information from the console.

Notes: I opend firefox with sudo

Executing /usr/bin/avconv -i /tmp/gizmodo_2249.mp4 -y -v 0 -strict experimental -ab 192k -f mp3 /home/jk/dwhelper/gizmodo_2249.mp3

The result was a 0 kB mp3-file.


I've decided to sudo-open firefox and remove VideoDownloadhelper. Then I opened Firefox as a nomal user with the terminal and installed the Add-On...Problem persists...Now I'm learning to use avconv.

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I checked the file (downloaded it) and it's videotrack is corrupt....that may be the reason that on-the-fy transcoding didn't work out for you.

Downloding the file is no problem. The only thing you have to do is convert it after you downloaded it. Open the terminal, go to the directory where you downloaded the file and invoke:

ffmpeg -i gizmodo_2249.mp4 -vn -acodec copy einstein.aac

And almost immediately you'll have exactly what you want: only audio in aac without transcoding so no quality loss.

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hmm...could you tell me what -vn menas? :P I'm still ignorant on that. – scjorge Nov 16 '13 at 1:30
-vn means "no video" or more accurately "drop the video stream" – thom Nov 16 '13 at 1:32
Thanks, would you vote up my question? :) – scjorge Nov 16 '13 at 1:44
Sure, no problem....can you mark my answer as the chosen answer ? ;-) – thom Nov 16 '13 at 1:49
Your answer is still not the correct one, it didn't fix the conversion capability of my download helper :/ – scjorge Nov 16 '13 at 1:53
up vote 0 down vote accepted

I've decided to apply "brutal apt-force" and installed the following packages:

libavcodec53, libavcodec-dev, libavcodec-extra-53, libav-tools, libavformat53, libavformat-extra-53, & libavformat-dev.

and the conversion worked! :)

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...but downloads from grooveshark still fail. – scjorge Nov 17 '13 at 23:08

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