International Journal of Innovation and Applied Studies ISSN 2028-9324 Vol. 3 No. 2 June 2013, pp. 560-569 © 2013 Innovative Space of Scientific Research Journals http://www.issr-journals.org/ijias/ Corresponding Author: Kalpana Saini (kal_2312@rediffmail.com) 560 Level set based on new Signed Pressure Force Function for Echocardiographic image segmentation Kalpana Saini 1 , M.L. Dewal 1 , and Manojkumar Rohit 2 1 Deptt. of Electrical Engg., IIT Roorkee, India 2 Deptt. of Cardiology, PGIMER Chandigarh, India Copyright © 2013 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT: In the present paper a novel region based active contour method is developed by formulating a new signed pressure force (SPF) function. The method has been applied to the echocardiographic images for getting the desired boundary. The method is useful for finding the automatic boundary detection of other images (Microbiological, MRI, CT, Natural and welding joint etc.) as well. Level set method in combination with original SPF has not been able to give satisfactory results during the segmentation of echocardiographic images. There are lots of noises present in the echocardiographic images those create difficulties in the segmentation process. The proposed method resolves all these difficulties in such a manner that the output image is having the proper boundary detection without any disturbances and noises. The very important advantage of this method is that it gives a very fast response in terms of time taken by CPU and the number of iterations. Fast response is very important in the clinical area especially in diagnosis purpose. The presented model is an advancement of Selective Binary and Gaussian Filtering Regularized Level Set (SBGFRLS) method. Proposed model is more robust against images with weak edge and intensity inhomogeneity when compared with the performance of earlier methods. KEYWORDS: Echocardiographic, Active contour, Signed pressure force function, Level set, Segmentation, Gaussian filtering, Regularized level Set. 1 INTRODUCTION Segmentation is a well-known step which is carried out for the clinical diagnosis from medical images. But the major problem encountered during the segmentation of echcardiographic images. The literature shows that the active contour based segmentation techniques are being extensively used in medical imaging [1-5]. Active contour models can be categorized as edge based active contour models [1-4, 6, 9, 10, 11] and region based active contour models [5, 7, 8, 12-14]. Some of the edge based active contour models are used as the edge-detector. The operation of edge detector depends on the gradient of the image to stop the initial contour on the boundary of the interested objects. This technique has advantage when the objects and background of segmented image are heterogeneous. Drawbacks of these active contour models are that the satisfactory results cannot be achieved in case of objects with discrete or with the presence of blur boundaries or noise. Some active contour models as in [6] introduce the balloon force to shrink and enlarge the capture range of the force. However some undesired effects occur during balloon method. If weak balloon force is there then contour is not able to pass through the narrow part of the object, and if the balloon force is large, the contour will pass through the weak edges of the object. The geodesic active contour (GAC) [4] is the most popular methods in this category. This method uses an edge stopping function (ESF) which stops the contour on the object boundaries.