I need a command line watermarking software or script for linux. It should work as such.
$videowatermark inputfile "text for watermark" [rgb font color] [fontbackgrouncolor] [1,2,3,4,5 for upper right,upperleft,bottom right,bottom left,center]
which would output either a mp4 or flash video file. Feel free to use any library available and I can supply you with an account on the build server.
As it's command line it doesn't matter what language it's written in and would be accessed with a php script using exec().