The effect of spatial discretization on the magnitude and direction response of simple differential edge operators on a step edge

✍ Scribed by L.J. Kitchen; J.A. Malin

• Publisher: Elsevier Science
• Year: 1989
• Weight: 888 KB
• Volume: 47
• Category: Article
• ISSN: 0734-189X
• DOI: 10.1016/s0734-189x(89)80009-x

✦ Synopsis

For a unit step edge, we calculate the gradient magnitude and direction reported by various simple differential edge operators as a function of the edge's actual orientation and offset with respect to the pixel grid. To be consistent with previous work (of Abdou and Prat 0 we have initially chosen to analyse (among others) the Sobel, Prewitt, and Roberts Cross operators, using a digitization model in which the pixels have uniform square receptive fields that tesselate the image plane. Our quantitative results provide insights into the behavior of these commonly used operators, insights that can guide their proper application in problems of image understanding and robot vision. We also suggest novel techniques for improving the performance of these operators. 9 1989 Academic Press, Inc.