A Multiscale Medial Description Of Shape In Grayscale Images

Abstract

We have developed a new representation of shape in grayscale images that does not rely on the detection of edges. Objects are described by computing features that indicate the geometric stucture of multiscale neighborhoods of each pixel. We define a multiscale medial axis (MMA) by considering the maximum resoponse over scale to the Laplacian operator at each pixel. The MMA is a connected ridgetop stucture. Associated with each pixel on the Mh4A is a width function determined by the scale at which the maximum response to the Laplacian occurs. This width function gives the approximate location of the object’s boundaries. The outputs of multiscale orientation-specific filters give estimates of axis orientation and boundary curvature. This image description has been shown to produce sensible regions for use in image segmentation and image registration applications.