Through a webpage you will, I imagine, need to build a COM control that is able to interact and detect a web cam connected to a users PC.
I am not sure what this involves as I have never done anything like this.
This article may point you in the right direction.
Read this if you want to know how to get a correct reply for your question:
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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