Patent ID: 7286709

Claim:
A motion detection apparatus for detecting a motion in an image frame inputted and stored in a time series, said apparatus comprising: a frame division section for dividing the inputted X-th image frame F(X) into a plurality of blocks B(X)ij, where i=1 to m and j=1 to n; a block luminance acquisition section for acquiring representative luminance values BLrep(X)ij of said blocks B(X)ij; a frame luminance acquisition section for acquiring a representative luminance value FLrep(X) of said inputted frame F(X); a storing section for storing BL(X)ij and FLrep(X); a block luminance difference calculation section for calculating block luminance differences ΔBLrep(X)ij between corresponding blocks in F(X) and a frame prior to F(X); a frame luminance difference calculation section for calculating a frame luminance difference ΔFLrep(X) between F(X) and a frame prior to F(X); an absolute difference calculation section for calculating absolute values |ΔBLrep(X)ij−ΔFLrep(X)|; a determination section for determining that a certain block includes a motion, if said absolute value for said certain block is greater than a prescribed threshold; and an output section for outputting the determination result, wherein: said determination section determines that: said certain block includes a motion, if said absolute value for said certain block is greater than a second threshold and moreover if either or both of said representative luminance values of the corresponding certain blocks in F(X) and a frame prior to F(X) is/are greater than a first threshold, where said first threshold is greater than said second threshold; or said certain block includes a motion, if said absolute value for said certain block is greater than a third threshold and moreover if both of said representative luminance values of the corresponding certain blocks in F(X) and a frame prior to F(X) are smaller than or equal to a first threshold, where said second threshold is greater than said third threshold.