Patent ID: 8577152

Claim:
A method of classifying an image, comprising: extracting a feature vector from the image, wherein the feature vector comprises a plurality of first features, each of the first features corresponds to a combination of a plurality of first areas arranged in the direction of a first axis, a plurality of second areas arranged in the direction of a second axis intersecting with the direction of the first axis, and one of a plurality of predetermined orientations, and the extracting of each of the first features comprises: acquiring a difference between sums or mean values of pixels of the plurality of first areas in the corresponding combination to obtain a first difference vector in the direction of the first axis, and acquiring a difference between sums or mean values of pixels of the plurality of second areas in the corresponding combination to obtain a second difference vector in the direction of the second axis; acquiring a first projection difference vector and a second projection difference vector projected by the first difference vector and the second difference vector on the line of the predetermined orientation in the corresponding combination; and acquiring the sum of magnitudes of the first projection difference vector and the second projection difference vector as the first feature; and classifying the image according to the extracted feature vector.