Hi,
iÃ,´ve recorded three videos how i learned scripting Avidemux with Spidermonkey. IÃ,´m from Germany so the things I explain are in german too but nevertheless the content can be understood by everyone also without sound. Therefore I post the link also here. Have fun with it.
http://www.youtube.com/watch?v=pqtthA0pSsQ&list=PLljFP_eLovZyB4iOUaq6GFB07Ih39xqsW (http://www.youtube.com/watch?v=pqtthA0pSsQ&list=PLljFP_eLovZyB4iOUaq6GFB07Ih39xqsW)