IMAGE DEVICE, SURVEILLANCE CAMERA, AND MASK METHOD OF CAMERA SCREEN

In a microcomputer included in an image device, a mask 2D 3D converting section expresses coordinates of a 2-dimensional image plane defined by an imaging element having a rectangular contour in a 3-dimensional coordinate system. The image plane is positioned in the state that a focal length corresponding to a zoom position is adopted as a Z coordinate value of the image plane in the 3-dimensional coordinate system. A mask display position calculating section 165 calculates a 2-dimensional position of a mask on a camera screen by utilizing a similarity of the size of the image plane and the size of the camera screen when a position of a mask on the image plane in the 3-dimensional coordinate system after PAN, TILT rotations and a zooming is converted into the 2-dimensional position of the mask on the camera screen.