Patent ID: 8494267

Claim:
An image processing device comprising: an obtaining unit which obtains image data of an image; a dividing unit which divides the obtained image into N blocks (N>1); a designation unit which sequentially designates M blocks (N≧M>1) among the N blocks as blocks to be updated, every time the image data of the image which is new is obtained; a histogram generation unit which generates a histogram of the designated M blocks of the image data; a histogram storage unit which sequentially updates and stores the generated histogram; a change determination unit which determines a change in the obtained image, on the basis of the degree of similarity between the histogram of the generated M blocks and the histogram of the M blocks in the past corresponding to the generated M blocks which are stored; a normalization determination unit which determines whether or not to perform normalization of the histogram; and a normalization unit which normalizes any one of the histogram of the generated M blocks and the histogram of the corresponding M blocks in the past which are stored, when the normalization is determined in the normalization determination unit, wherein the change determination unit determines the change in the obtained image, on the basis of the degree of similarity using the histogram after the normalization, when the normalization of the histogram is performed, using the normalization unit.