If you want to record (or create from individual frames) use mencoder ( part of the mplayer package). You can see how it can be controlled from Perl in ztk-v4l-video-bloger/recorder and a rip-process-reassemble can be seen in z-charcoal-video-converter

Also you can search google and groups.google for mencoder, to find the difficult syntax strings to do what you want. Mencoder can be VERY FINICKY about syntax.

I'm not sure what you mean by create video from text commands.