This is the quickest option for most users. FFmpeg from the repository does not include many restricted encoders, formats, and codecs including: h263, aac (libfaac), mp3 (libmp3lame), h264 (libx264), xvid (libxvid), and mpeg4. You can fix this by installing the unstripped or extra (Ubuntu Karmic renamed unstripped to extra) FFmpeg libraries that will enable these restricted encoders. Open up Terminal and enter:
Ubuntu Karmic Koala 9.10
Code:
sudo apt-get install ffmpeg libavcodec-extra-52
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