Edge Detector

Modified on 2011/03/18 16:39 by Administrator — Categorized as: Digital Image Processing

Edge

Points where a large change in image brightness over a short spatial distance occurred
is defined by a discontinuity in gray-level values

Roberts Operator

It is the simplest of the edge detection operators and will work best with binary images.

Sobel Operator

Prewitt Operator

Derivative operator

Zero-crossing

Laplacian Gaussian

Laplacian of Gaussian (LoG)

Difference Of two Gaussian : DOG

Edge Detector

Edge Detector - Noise

(a) Original image. (b) Image with added noise. (c) Sobel with a 3x3 mask. (d) Sobel with a 7x7 mask. (e) Prewitt with a 3x3 mask. (f) Prewitt with a 7x7 mask. (g) Result from applying a threshold to the 3x3 Prewitt. (h) Result from applying a threshold to the 7x7 Prewitt. (i) Truncated pyramid with a 7x7 mask. (j) Results from applying a threshold to the 7x7 truncated pyramid.