Boundaries As Unpredictable Discontinuities
Richard J. Gleeson, Josef Skrzypek · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1989
A large part of the information content of an image is conveyed by the location of pixels that determine the boundaries between different segments. In absence of prior knowledge about objects in the scene, it is impossible to predict where the edges will occur. The gray levels at locations away from boundaries are often highly correlated. They can be estimated from the values of nearby locations using assumptions based on our knowledge of the physical laws governing reflections from surfaces. Boundaries occur at points of essentially infinite variation. At these points corresponding gray levels result from summing energy reflected by two different regions and cannot be easily estimated from the values at nearby pixels. In this sense gray level values at discontinuities are less predictable.