| 20090255776 | Coin authenticity judging method and device - Image data of an incuse/relief portion, formed on a surface of a medal, are acquired by capturing an image of the incuse/relief portion with an image sensor, disposed so as to oppose the medal substantially straightly, while illuminating light from a light source disposed obliquely above the medal, and image processing using two or more predetermined threshold values to multinarize brightness information, including shading related to the incuse/relief portion, in the acquired image data into three or more values is performed. By the image processing of multinarization into the three or more values, the medal surface is regionally divided into at least a profile region, a top surface region, and a bottom surface region in the incuse/relief portion and compared to an authentic medal. | 10-15-2009 |
