What ports to block to prevent webcam usage ?

Archived from groups: alt.comp.periphs.webcam (More info?)

I've read about Yahoo port 5100 for webcam access. Are there any other
"standard ports" which can also be filtered to block outgoing webcam without
blocking everything ?

I want it avail. sometimes, but want to prevent it other times. Are the
ports used based more on the webcam application, and a standard ?

Any help is appreciated.