Does anyone know how to run a batch command to make thumbnail images for .flv files using ffmpeg-php

I recently I had to move to another server. The transfer went well but the thumb nail images where lost to all the video`s and i do not know how to get them back.

The script is Vshare ( http://stonerocket.net/vidz ) theres about 400 video`s that I need to create the thumbnails for.
I really to not want to start over again because I get a reasonable amount of traffic to it.


Any help would be kindly appreciated.