An image processing device is provided. The image processing device includes a control unit, a first storing zone, a frame buffer register, a first buffering zone and a first image processor. The first storing zone is electrically connected to the control unit and storing therein a first image frame. The frame buffer register is electrically connected to the control unit and the first storing zone, and performing a first image processing operation on the first image frame in response to a first control signal from the control unit so as to form a first processed frame. The first buffering zone receives and stores the first processed frame from the frame buffer register. The first image processor is electrically connected to the first buffering zone and processing the first processed frame into a first image signal in response to a second control signal from the control unit.