Abstract In this paper, a new method for edge preserving image segmentation based on the Gaussian Mixture Model (GMM) is presented. The standard GMM considers each pixel as independent and does not incorporate the spatial relationship among the neighboring pixels. Hence segmentation is highly sensitive to noise. Traditional smoothing filters average the noise, but fail to preserve the edges. In the proposed method, a bilateral filter which employs two filters- domain filter and range filter, is applied to the image for edge preserving smoothing. Secondly, in the Expectation Maximization algorithm used to estimate the parameters of GMM, the posterior probability is weighted with the Gaussian kernel to incorporate the spatial relationship among the neighboring pixels. Thirdly, as an outcome of the proposed method, edge detection is also done on images with noise. Experimental results obtained by applying the proposed method on synthetic images and simulated brain images demonstrate the improved robustness and effectiveness of the method.

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[18] Zhang Y., Tian X., and Ren P., An ADaptive Bilateral Filter Based Framework for Image Denoising, Neurocomputing, vol. 140, pp. 299- 316, 2014. Edge Preserving Image Segmentation using Spatially Constrained EM algorithm 933 Meena Ramasamy is Associate Professor, Department of Electronics and Communication Engineering, Sethu Institute of Technology, Kariapatti, India. She has received her Ph.D., in the year 2017 from Anna University, India. Her publications include 11 research papers in international journals and 12 in international conferences. She is a life member of IETE. Her area of interests includes Image Processing and Embedded Systems. Shantha Ramapackiam is Senior Professor and Head, Department of Electronics and Communication Engineering, Mepco Schlenk Engineering College, Sivakasi, India. She has received her Ph.D., in the year 2008 from MS University. She is having 30 Years of Teaching and Research experience in the field of ECE. Her publications include more than 80 research papers in international journals and more than 100 in conferences. Presently she is guiding research scholars in the area of Biosignal Processing, Image Processing and Digital Communication. She is a life member of FIETE, ISTE and CSI. She also serves as Editorial Board Member and as program Committee Member for several International Journals and Conferences.