Regenerate thumbnails for flvs?

Is there a way to regenerate the thumb nails in Gallery 3 for flv and mp4 files that were previously in Gallery 2? I have a slew of movies i would love to update the images for without having to reupload them. I converted from Gallery 2 to 3 i think around beta 2 or 3.

http://photos.jasonhardin.com/index.php/jasonnsarah/movies?page=2&amp%3B_=2&_=1

Is this something maybe I could write a script against the Restful web service to do?