It is more then likely that you are not going to get it to do what you want, not with PHP anyway. You want to google for a program that would allow you to access the remote camera.
One easy method i've used before is to set up 2 skype accounts, and leave one running on the computer with the webcam. Set the settings to automatically accept video calls from friends only, then add the 2nd skype account as a friend. Whenever you want to view the feed, just call the account attached to the webcam, then end the call when you're done.
Works well when going on vacation, as long as the power doesn't go out...
