How to change the format of the movie file

Use a shell command like convert to split up movie.gif with multiple layers into multiple frames, as seperate jpeg files:
convert movie.gif %d.jpg
Convert any series of multiple jpeg files into WMV format with:
mencoder 'mf://*.jpg' -mf type=jpg:fps=25 -ovc lavc -lavcopts
vcodec=wmv2 -o movie.wmv
To convert a video file into avi format use this command:
mencoder <videofile> -ovc lavc -lavcopts vcodec=flv -of avi -o movie.avi
In general:To convert a video file from one format into the other, use the program "mencoder". It comes with the mplayer packages.
mplayer movie.wmv