Abstract—This paper proposes a method of encoding a color image into n meaningful halftone shares using the scheme of halftone visual cryptography. The proposed method encrypts the color image into high-quality n halftone shares generated via direct binary search (DBS) with adaptive search and swap method. This scheme achieves lossless recovery and reduces the noise in the shares without any computational complexity. Simulation results show that the visual quality of the obtained halftone shares are observably better compared with previous algorithms.

Index Terms—Visual secret sharing, halftone visual cryptography, direct binary search, adaptive search

N Krishna Prakash is with the Electrical and Electronics Engineering Department, Sri Krishna College of Engineering and Technology,Coimbatore, India (e-mail: nkrishnaprakash@rediffmail.com).
S Govindaraju is with the Electronics and Communication Engineering Department, Kumaraguru College of Technology, Coimbatore, India (e-mail:sgraju_kct@hotmail.com).

Cite: N Krishna Prakash and S Govindaraju, "Visual Cryptography Scheme for Color Images Using Half Toning Via Direct Binary Search with Adaptive Search and Swap," International Journal of Computer and Electrical Engineering vol. 3, no. 6, pp. 900-904, 2011.