In the proposed method, the encoding time is reduced by combining iteration-free fractal compression technique with fuzzy c-means clustering approach to classify the domain blocks. In iteration-free fractal image compression, the mean image is considered as domain pool for range-domain mapping that reduces the number of fractal matching. Discrete Cosine Transform (DCT) coefficient is used as a new metric for range and domain blocks comparison. Also fuzzy clustering approach reduces the search space to only a subset of domain pool. Based on Fuzzy clustering on DCT space, the domain pool is grouped into three clusters and the search is made in any one of the three clusters. The proposed method has been tested for various standard images and found that the encoding time is reduced about 42 times than the iteration-free fractal coding method with only a slight degradation in the quality of images.

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[21] Zhou Y., Zhang C., and Zhang Z., “An Efficient Fractal Image Coding Algorithm using Unified Feature and DCT,” Chaos, Solitons and Fractals, vol. 39, no. 4, pp. 1823-1830, 2009. Sobia Mahalingam obtained M.Sc and M.Phil, Degree from Thiruvalluvar University in Computer Science. She is currently pursuing Ph.D. in Computer Applications in Anna University, Chennai. She has published papers in National and International Conference. Her area of interest includes Image Processing and Optimization Techniques. Valarmathi Lakshapalam is presently working as Associate Professor in the Department of Computer Science and Engineering, Government College of Technology, Coimbatore, India. She received her Ph.D (Computer Science and Engineering) from Bharathiar University, Coimbatore. Her research comprises Image Processing, Optimisation Techniques, Data Mining and Network Security. She has published 80 technical papers in National and International conferences and 81 papers in International Journals. Saranya Ekabaram is currently working as Assistant Professor, Department of Computer Science and Engineering, V.S.B College of Engineering Technical Campus, Coimbatore, India. She received her B.Tech.(IT) and M.E. (CSE) from Anna University, Chennai. Her area of interest includes Image Processing and Networks.