A writing unit writes first and second divided images on a frame memory. A reading unit adds an end portion included in the second divided image to the first divided image and reads the result as a first read image from the frame memory. Also, the read unit reads the second divided image as a second read image from the frame memory. An image processing unit performs image processing for the first and second read images read from the frame memory. A cutting unit cuts a second sub-end portion from the first read image after the image processing and outputs the result, and cuts a first sub-end portion from the second read image after the image processing and outputs the result.