Blender Game Engine provides capability to use video sources as textures. Problem is it uses ffmpeg and it’s not very good for access to Windows webcams. I’ve came across this problem recently and found a workaround – external python module VideoCapture. It uses DirectShow so it should be able to use almost every webcam on Windows.
Blender 2.62 uses Python 3.2, so it’s necessary to find module built for for this version. It’s located on Python Extension packages for Windows page. Choose proper build (VideoCapture-0.9.4.win-amd64-py3.2.exe or VideoCapture-0.9.4.win-win32-py3.2.exe) and install it into your Python installation.
If Blender doesn’t recognize installed module, copy file vidcap.pyd and folder VideoCapture to folder 2.62\python\lib in Blender installation. Then it should work correctly.
I made a basic example. It creates dynamic texture, webcam device and it loads image from device to texture every frame. Device ID is defined as object’s property.