Pixels feature extraction method for the corresponding point search, and the corresponding point search method of stereo images

摘要

PROBLEM TO BE SOLVED: To reduce the detection rate of corresponding points or miscorrespondence as to a corresponding point search by a stereoscopic image method. SOLUTION: A gradation converting means 12 converts a right and a left (m)-gradation source image into a right and left (n)-gradation converted image and a pixel group detecting means 18 pays attention to one kind among 1st-(n)th (n)-gradation density sections and scans the right and left (n)-gradation converted images as to the density section of interest to detect a right and a left pixel group of interest consisting of pixels belonging to the density section of interest in a horizontal scan. A feature extracting means 24 scans the right and left (m)-gradation source images as to the detected right and left pixel groups of interest to extract pixel features. When a corresponding point search is made, right and left pixels whose pixel feature differences are within a permissible range in the right and left pixel groups of interest are detected as corresponding points.