If you want to work with a live camera and use the feed, you can use this simple recipe to see the simplistic workings. This project is a great opener for demonstrating Flex too. You can build this from scratch in about 2-3 minutes.
Solution
Note that this is tooled to work with Flex Builder 3, beta 3. When working with the Camera class, you can pass a named camera to the getCamera method. If you only have one camera, the application will use it by default. If you get nothing, you can right click (Ctrl click on Mac) the <mx:VideoDisplay> in the application and chose your device.
public var myCamera:Camera; public function startCam():void { myCamera = Camera.getCamera(); myVid.attachCamera(myCamera); myVid.autoPlay; } ]]> </mx:Script>