Video conversion and resolution resizing script

Hello Yes i am running a linux server and i need a script in either PHP or PERL which ever is easier that can open various video formats AVI, WMV, MP4 and other formats convert them to an Flash FLV file and i also need to have the option to resize the video resolution to a specified resolution and i also need to have the audio kept intact to. a function or set of functions that you provide source and destination location and filename and also as an optional parameter is the width and height of the flash FLV video. If you have any questions feel free to ask. Thanks,