Patent ID: 7006693

Claim:
An object recognition method, which recognizes objects by utilizing the density difference of the object and the background area shown on an image, said method comprising: arranging points p at equal intervals on said image, for said respective point p, performing a fundamental wave Fourier transformation for each pixel value on a circumference of a circle which center is point p, handling a phase obtained from said fundamental wave Fourier transformation as the normal vector of said point p, recognizing said object from the normal vector group of every said points p arranged at equal intervals, and judging that a normal vector does not exist for a point p when a value of a square root of a square sum of a value SV (which is the product sum of the sine wave of the fundamental wave Fourier transformation), and a value CV (which is the product sum of the cosine wave of the fundamental wave Fourier transformation) is below a fixed value or when a sum of an absolute value of said SV and said CV is below a fixed value.