Industrial parts recognition and inspection by image morphology

Application algorithms for industrial parts and tool recognition and inspection by image morphology techniques are discussed. A recursive adaptive thresholding algorithm transforms a gray-level image into a set of multiple-level regions of objects. This algorithm uses a morphological erosion with a large symmetrical concave structuring element. A distance-transformation algorithm transforms these binary image regions into the minimum distance from each object point to the boundary of the object. This algorithm also uses a morphological erosion. From the distance transform, it is possible to compute a shape number and extract the skeleton, which is useful for generic pattern recognition and feature extraction. Corner angles and the radii of circular holes can be located, identified, and estimated by using morphological openings and erosions. The algorithms allow robust tool and part recognition and inspection