Custom Camera Activity for Android

I need a CustomCameraActivity for Android in which you have the usual button to make a photo. The activity will work only in landscape orientation. This activity have to show a rectangle (use constants for lenght) in the middle of the screen; the internal area of the rectangle should be normal, instead the rest of the area should be blurred (this behaiour should be disabled with a boolean constant). In the right top corner of the screen should be a light (red/green). The light has to be green only when X,Y,Z angle is whitin a value of 2° (constant in the app that I can change); so the tablet is perpendicular to the floor and parallel to the subject to be photographed. You should provide this activity and a TestMain class that invoke this activity and display the photo returned from CustomCameraActivity.