Patent ID: 7149364

Claim:
A mean filter device comprising: first integrating means integrating a predetermined number of pieces of pixel data disposed in periphery of each pixel in a first linear direction in a pixel data matrix forming a two-dimensional image, and thus generating first integrated pixel data of each of the pixels; second integrating means integrating the first integrated pixel data corresponding to a predetermined number of pixels disposed in the periphery of each of the pixels in a second linear direction, and thus generating second integrated pixel data of each of the pixels; and means dividing the second integrated pixel data by the number of pixels integrated in the first linear direction and in the second linear direction; and wherein said first integrating means includes first adding means adding the input pixel data inputted and the pixel data already integrated before inputting the input pixel data, and addition retaining means retaining the already-integrated pixel data, a first subtracting means includes input retaining means retaining the predetermined number of pieces of input pixel data in sequence, and a first subtracter subtracting, from an output of said first adding means, the input pixel data disposed apart by the predetermined number of pieces of pixel data from the now-inputted pixel data and outputting the subtracted result as a predetermined pixel integrated value to said addition retaining means, and said addition retaining means feedback-outputs the predetermined pixel integrated value to said first adding means for a next addition.