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Ok, this one has me scratching my head - and being a n00b isn't helping.

In short, I had a script which I had perfected to covert MKV video to MP4.

However, my Ubuntu 10.10 box bit the dust and installed 11.04.

However, my script is now having problems with the following line:

ffmpeg -i "${title}".ac3 -acodec libfaac -ab 576k "${title}".aac

When it reaches the relevant stage in the script, it returns the error:

Unknown encoder 'libfaac'

I have tried swapping libfaac for aac, which seems to be installed/recognised by ffmpeg - however that codec is just way too slow.

I have no idea how to either;

  1. get libfaac back on my Ubuntu 11.04 install, or
  2. find a better codec than AAC to convert the audio.

Any help to point me in the right direction is greatly appreciated.

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up vote 2 down vote accepted

try this: go to system/Administration/synaptic and type libfaac and install it.

if did not work try to install the FULL-FFMPEG from here. The ffmpeg package which comes with Ubuntu is incomplete.

share|improve this answer
Genius. Thank you for pointing me in the direction of that thread, exactly what I was looking for and solved the problem perfectly. – thewinchester May 2 '11 at 14:30

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