Ubuntu is a free Linux-based operating system that has grown in popularity. Like most Linux-based operating systems, some tasks require you to use the command line rather than a graphical user interface. This includes converting an MKV movie file to an AVI file. Follow a few guidelines to use the command line for your video conversion.
Download and Install Automatix in Ubuntu. Type the following in the command line to download Automatix:
$ cd /tmp" then type "$ wget http://www.getautomatix.com/apt/dists/edgy/main/binary-i386/automatix2_1.1-2.15-6.10edgy_i386.deb
To install Automatix type:
$ sudo dpkg -i automatix2_1.1-2.15-6.10edgy_i386.deb
This will successfully install Automatix in Ubuntu.
Start Automatix by typing:
$ automatix2 &
Click the "Enter" key.
Download and install MPlayer. Type the following in the command line:
$ automatix2 &
Click on "Mplayer and FF," "Multimedia Codecs" and "AUD-DVD Codecs," then click the "Start Button." Mplayer is a freeware program that contains Mencoder, which converts MKV to AVI.
Convert the MKV file to AVI file. Type the following in the command line:
mencoder my_video.mkv -ffourcc xvid -ovc lavc -lavcopts vcodec=xvid:vhq:vbitrate=1800 -oac mp3lame -lameopts vbr=5 -o output_video.avi"
Change the "my_video.mkv" to the name of the MKV file you wish to convert. The file will be converted to an AVI file automatically. The file will be located in the same folder as your original AVI file. If you get an error message while converting the MKV file, change the line "-oac copy" to "-oac pcm" in the encoding command and try again.
All the programs are open source and free to use; there is no other software suite that can convert all types of MKV files to AVI files like Mencoder, as of July 2011.