Visual Secret Sharing Scheme: Improving the Contrast of a Recovered Image Via Different Pixel Expansions

  • Ching-Nung Yang
  • Tse-Shih Chen
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4141)


Visual secret sharing (VSS) scheme is an image sharing scheme that divides a secret pixel into several sub pixels (the number of sub pixels is called the pixel expansion) and the secret image is visually revealed without additional computations. However the contrast of recovered image is poor and thus the VSS framework is always a research issue and not a practical scheme. In this paper, we introduce a new framework which prioritizes the pixels with different pixel expansions to reconstruct a high-quality image for practical use. Also, integrating the optical character recognition with the proposed VSS scheme we show a new automated visual authentication scheme.


Human Visual System Secret Image Optical Character Recognition Shadow Image Visual Cryptography 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Ching-Nung Yang
    • 1
  • Tse-Shih Chen
    • 1
  1. 1.Department of Computer Science and Information EngineeringNational Dong Hwa UniversityHualienTaiwan

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