i need to connect to a webcam

[anurupr]

i need to make a "firewall" for a webcam. basically i need to control who and what accesses the webcam. so before that i should know how to connect to a webcam. i've been doing alot of research on this but it has all been in vain. i did find something about interrupts. so i figured if i knew which interrupt would be called i would be able to monitor if the webcam is accessed or not. but im looking for a more high level solution . can anyone please help me out?