Patent ID: 8300978

Claim:
A projector configured to correct a keystone distortion of an image, and to display a post-correction image, the projector comprising: a frame memory configured to store a pre-correction image; an image composition circuit configured to: i) execute reordering so that pixel data constituting each cache block is stored in an area with contiguous addresses, and ii) store an image obtained by the reordering in the frame memory as the pre-correction image; a block data storage memory configured to store the pre-correction image by block data comprising M pixels in a first direction and N pixels in a second direction (M, N≧2), and provided with a capacity capable of storing n×N (n≧2) lines of the pre-correction image; a correction section configured to correct the pre-correction image based on the block data stored in the block data storage memory; and a control section configured to obtain the pre-correction image from the frame memory by the block data, and also configured to store the obtained pre-correction image in the block data storage memory, wherein the control section obtains contiguous n×N (n≧2) lines of the image from the frame memory and stores the obtained image in the block data storage memory at the beginning of the correction process, and in a subsequent process, if the block data to be the object of the processing is absent from the block data storage memory, obtains the block data from the frame memory, and overwrites block data which is farthest from obtained block data in the second direction in the pre-correction image with the obtained block data.