This howto will show you the shortest way to convert flv (flash video) files to AVI using open source mencoder. To perform the conversion, you just need to type :
mencoder -oac copy -ovc lavc -o video.avi video.flv
What is FLV files?
FLV (flash video files) is a format for delivering video through the internet, it is currently being use by the popular Youtube video sharing service and Google Video. It is possible to obtain this file by using other open source tools such as youtube-dl or from an online youtube downloader VideoDL.org
You can convert the FLV files into other format too. In order to do that, make sure you have all the necessary codecs to perform the conversion. If you’re in doubt, install w32codecs, add this line in your repository to enable w32codecs installation (assuming you use Ubuntu Edgy Eft).
deb http://packages.freecontrib.org/ubuntu/plf/ edgy free non-free
deb-src http://packages.freecontrib.org/ubuntu/plf/ edgy free non-free
Now you can use Linux as to do your video encoding stuff without much hassle.