GRAPHIC CENTER DETECTION METHOD, ELLIPSE DETECTION METHOD, IMAGE RECOGNITION DEVICE AND CONTROLLER

• Main Authors: FUJIYOSHI HIRONOBU, TAKAMARU TAKANORI, SAKASHITA YUSUKE, FUKAYA NAOKI
• Format: Patent
• Language: English
• Published: 28.06.2007
• Subjects: CALCULATING; COMPUTING; COUNTING; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; PHYSICS

PROBLEM TO BE SOLVED: To provide an ellipse detection method for detecting an ellipse in an input image with small processing quantity and an image recognition device for executing the detection method and a controller for executing various control using an ellipse detected from the input image with a small time lag from the photographing of the image. SOLUTION: One target graphic in image data is extracted, and the center of gravity of a parallelogram inscribed in the target graphic with A point, B point, C point and D point as vertexes while a first distance and a second distance are matched is detected. Then, count at the position corresponding to the position of the center of gravity of the parallelogram of a central point candidate map preliminarily set on a memory having a coordinate system corresponding to the pixel positions of the image data is increased, and the position of the central point whose count is large on the central point candidate map is extracted as the central point of the target graphic. Furthermore, an ellipse equation is solved by using the vertex positions of a plurality of parallelograms having the center of gravity at the same position as the position of the central point of the target graphic, and the restored ellipse is compared with the candidate graphic so that the ellipse can be detected. COPYRIGHT: (C)2007,JPO&INPIT