7. (10 points) Consider a camera system where the camera is pointed at a distant circular object of radius r. Consider that the camera image plane is parallel to the circular object's plane. The camera is placed at a distance of a meters from the object. The object is b meters above the camera and c meters along the left direction of the camera view. The camera is rotated by 90 degrees about the line joining the camera and the object. The camera focal length is f, pixel side lengths (s,s) and principal point (o, oy) (a) What would the shape of the originally circular object be on the camera image? (b) What would the size of the object be on the camera image if its area in real world is 314 cm (b) If (lcam, Vcam) are the pixel coordinates of the center of the circle on the image. Determine the radius of the circle r (in terms of the parameters given. Derive it completely)