To computers, all images are simply two dimensional arrays of numbers. To these arrays, machine vision systems apply specialized functions that produce numerical measurements as intermediate or final results. Some examples of vision functions include:
Many vision functions produce measurement values such as part dimensions that must be validated against manufacturing specifications. Also, some vision functions produce a numerical score which indicates the strength or confidence with which a part, defect, or character was detected. Vision systems compare these dimensions and scores against fixed limit values so that the manufacturing system can automatically identify and reject bad parts.