Method of identifying and characterizing a valid object by color

The present invention relates to a method of identifying and characterizing, by color, at least one valid object having at least one predetermined attribute value in a background. The method generates a plurality of images of a candidate object and the background, where each image is one of three primary color images or a black-and-white image. The method searches the image for a candidate object using an automatically calculated threshold gray level and determines the interior points of the candidate object. The method further determines the gray level value of the interior points in the image and calculates a color parameter for the interior points. The method thus enables one to characterize the candidate object by the color parameter and validate the candidate object having the valid object predetermined attribute value.