Any significant change in image pixels’ intensity can produce the edge that appears as the boundary that isolates various image regions. According to image amplitude changes, edges can be modeled into different types such as; Step, Ramp, Ridge /Line, and Roof Edges. Image edge detection techniques usually reduce the amount of information and ignore the useless data with preserving main image properties, however, Edge detection techniques are mainly grouped into two categories, Gradient and Laplacian edge detection techniques. This paper introduces different concepts related to edges, and discusses essential characteristics of various edge detection techniques.
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Digital image processing, Edge detection, Gradient methods, Laplacian methods.