mp4 video conversion

Hi All,

I've made script in 2012a using the VideoWriter class on a windows 7 PC. The script takes in an .xvid file and converts it to .mp4

However most of the machines this code may need to be run on are 2011a, they will be upgraded to 2012a soon but they will still be on windows XP and according to the doc on VideoWriter .mp4 files can only be created on windows7 systems.

So my question is is there a way to write .mp4 files in either 2011a/2012a running on Windows XP?

Or are there any third party (free) command line tools that I can call from Matlab and parse the video to and it spits out the .mp4 file?

cheers,
Ollie