Edge detection using sobel method with Median filter

In this paper we show a very good approach to detect edge and corner of any image. Edges and corners are very important part of an image. Edge detection is a commonly performed operation in image processing. Many different edge detectors were used in edge detection. However, the results may not be satisfied when they are directly used in digital images which are affected by noise. Therefore, it's necessary for us to smooth the noise before detecting edges This paper proposes an improved algorithm which used the Sobel operator to detect the edges with median filter to remove the unwanted noise of an image; we also calculate the PSNR value with median filter for better performance. This paper compares and analyzes several kinds of image edge detection, including prewitt, Robert and canny with matlab tool. The experimental results on standard test images demonstrate this filter is simpler and better performing than average filter and also detect the edges accurately. KeywordsEdge detection, Sobel operator, Median filter.