Patent ID: 7920756

Claim:
An image processing device that processes an image constituted as a collection of blocks consisting of a plurality of pixels, the image processing device comprising: an image data input unit that inputs image data constituted by recording for each of the blocks a coefficient obtained by converting a space area to a frequency area performed using the blocks as a unit; an edge pattern storage unit that stores correlated to each other a basic edge pattern for which a gradient shape representative of a change in the pixel values within the block is expressed by the coefficient, and a pattern number uniquely allocated to the basic edge pattern; a coefficient extraction unit that extracts a coefficient group that express frequency elements of a specified direction from each block of the input image data; a pattern matching unit that selects from the edge pattern storage unit the basic edge pattern similar to the gradient shape expressed by the extracted coefficient group; a pattern number storage unit that stores the pattern number corresponding to the selected basic edge pattern, wherein the pattern number is associated with the block; and a blur width detection unit that references the pattern number stored in the pattern number storage unit, and detects the blur width based on a range for which a basic edge pattern gradient direction matches along a series of the blocks within the image.