In this paper, a new (k, n) threshold Secret Image Sharing Scheme (SISS) is proposed. In the proposed scheme the secret image is first partitioned into several non-overlapping blocks of k pixels. Every k pixel is assumed as the vertices of a complete graph G. Each spanning tree of G is represented by k pixels along with Prüfer sequence and used to form k pixels of a share image. The original secret image can be restored by k or more shares and cannot be reconstructed by (k-1). The experimental results indicate that the proposed SISS is an efficient and safe method.

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[20] Zhao R., Zhao J., Dai F., and Zhao F., “A New Image Sharing Scheme to Identify Cheaters,” Computer Standard and Interfaces, vol. 31, no. 1, pp. 252-257, 2009. 456 The International Arab Journal of Information Technology, Vol. 14, No. 4, July 2017 Amitava Nag received his M. Tech. degree from University of Calcutta,Kolkata,India in 2005. Currently he is working as an Assistant Professor and Head in Dept. of IT, Academy of Technology, India and also working towards his PhD at the Dept. of Engineering and Technological Studies, University of Kalyani, India. He is a member of IEEE, ACM and CSI. His areas of interest include Image Processing, Information Security, and Data Mining. Sushanta Biswas obtained his Ph.D in engineering from Jadavpur University in the year 2004. He obtained his M.E from Jadavpur University and B.E from Bengal Engineering College (Presently known as Bengal Engineering and Science University, Shibpur) in the year 1994 and 1990 respectively. He is presently working as Associate Professor in the Dept. of Engineering and Technological Studies, University of Kalyani. He has more than 14 years of teaching experience. His area of interest includes, Artificial Neural Network, Image Processing, Frequency Selective Surfaces, Microstrip Antennas. Debasree Sarkar has obtained her Ph.D degree in Engineering from Jadavpur University in the year 2005. She has obtained her M.E and B.E from Bengal Engineering College (presently known as Bengal Engineering and Science University, Shibpur) in the year 1994 and 1991 respectively. She is presently working as Associate Professor in Dept. of Engineering and Technological Studies, University of Kalyani. She has more than 14 years of teaching experience. Her area of research includes Artificial Neural Network, Microstrip Antenna, Frequency Selective Surfaces, and Embedded Systems. Partha Sarkar obtained his Ph.D in engineering from Jadavpur University in the year 2002. He has obtained his M.E from Jadavpur University in the year 1994. He earned his B.E degree in Electronics and Telecommunication Engineering from Bengal Engineering College (Presently known as Bengal Engineering and Science University, Shibpur) in the year 1991. He is presently working as Professor and Head at the Dept. of Engineering and Technological Studies, University of Kalyani. His area of research includes, Microstrip Antenna, Microstrip Filter, Frequency Selective Surfaces, and Artificial Neural Network. He has contributed to numerous research articles in various journals and conferences of repute. He is also a life Fellow of IETE.