As I understand the webcam isn't displaying an image,
No worries as I'd love to help, however, I need a few more details to provide an accurate solution:
Did you try using any other application with your webcam such as skype or youcam?
Have you attempted a system restore to an earlier time it had been working?
In the meantime, if it isn't working on other apps either, here's a related post that seems to have helped others: Click here
(Though the header may be different, the solution should work for your concern as well).
For troubleshooting the webcam issues:
You can open webcam software, such as YouCam, Skype, or Live Messenger, but the video does not display in the main viewing window. Use the following steps, in the order, they are presented, until the webcam video displays in your webcam software:
Step 1: Make sure the webcam is the selected video/capture device for your webcam software
Your webcam must be selected as the video capture device in your webcam software. If the computer has multiple video input sources, your webcam software might be connected to something other than your webcam.
To select the webcam as your video source, open your webcam software and look for the video camera, video source, or video caption in the software's properties or preferences. Here are some common examples of selecting the webcam as the video source:
The name of your webcam might display as USB Video Device, HP Webcam, USB 2.0 Camera, HP Pavilion Webcam, or similar. If you do not know the name, select a name to see if video displays. If not, try selecting other video device names until you see the video from your webcam display in the window.