A Theoretical Survey for Edge Detection Techniques and Watershed Transformation

Edge is a boundary between two homogeneous regions. Edge detection is a preprocessing step in image analysis. It is a most difficult task in image processing. Edge in an image are with strong intensity contrast. A jump in intensity from one pixels to the very next, which effects in the quality of the picture. A quality of picture is characterized by the sharp discontinuities in an image. Hence a challenge to detect an edge while preserving the important structural properties of an image is challenge. In this paper our main aim is been made to survey the theoretical concepts of commonly used edge detection methods in digital image processing.