Comment: Frame job (Score 1) 232
In theory, since a movie is just a series of still frames, the same techniques could be used to modify individual frames as are used to "photoshop" a still image, (albeit, tediously). You might find the tools and tutorials at this site of some help in analyzing individual frames: http://fotoforensics.com/
You might also find some of the information at the associated Hacker Factor blog of use: http://www.hackerfactor.com/blog/index.php?/categories/17-FotoForensics