International Journal of Scientific & Technology Research

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IJSTR >> Volume 3- Issue 4, April 2014 Edition

International Journal of Scientific & Technology Research  
International Journal of Scientific & Technology Research

Website: http://www.ijstr.org

ISSN 2277-8616

Improving Image Quality In Extended Visual Cryptography For Halftone Images With No Pixel Expansion

[Full Text]



J. Tamilarasi, V. Vanitha, T. Renuka



Index Terms: extended visual cryptography, image processing, improving image quality, secret sharing, visual cryptography



Abstract: Visual cryptography is a secret sharing scheme that divides secret images into shares such that, when the shares are superimposed, a hidden secret image is revealed. In extended visual cryptography, an extra security is provided by giving cover images to the shares. However, in either case, loss of resolution, contrast, and image size expansion are challenging problems that the researchers are facing. In this paper, we propose a method for processing halftone images that improves the quality of the recovered images and also avoids pixel expansion. The resulting scheme maintains the perfect security of the original extended visual cryptography approach and also provides a better result.



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