A low complexity dual mode edge detector

Edge detection is widely applied in digital image processing, especially in segmentation of images. Many of the well-known edge detectors, e.g., Sobel and Canny operator, are based on spatial filtering with a mask around the pixel under detection. In this paper, we propose a very low complexity edge detector that has two operation modes; non-causal mode and causal mode. Though simple in its form, the proposed two operation modes can pick out pixels around boundaries effectively and efficiently. For images with salt-and-pepper noise, the proposed approach offers a much better noise immunity than that of by Sobel operator. Experimental results are also given to demonstrate the superiority of the proposed approach.