Shift-Tolerant Visual Secret Sharing Scheme without Pixel Expansion

• Main Authors: Yung-Chang Chen, 陳永昌
• Other Authors: Justie Su-Tzu Juan
• Format: Others
• Language: en_US
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/52555593990319395082

碩士 === 國立暨南國際大學 === 資訊工程學系 === 104 === Visual secret sharing(VSS) is a technology of image encryption, which does not requir any calculation at the time of decryption, just alone with the human visual system then the secret can be recovered. The concept of VSS is encrypting a secret image into two meaningless shares. We can only decrypt the secret image by stacking these shares together. Random grid, which is a skill for making a visual secret sharing scheme, the advantage is that it does not need the codebooks, and the size of each share will be the same size as the secret image. It is a simple and useful technique to share secret image. However, there would be problems in alignment when these two shares are staked by hand in practical. Therefore, this thesis presents the fault-tolerant schemes when stacking two shares that are acquired from secret image encryption without pixel expansion. When two shares are stacked, even without been perfectly stacked, we can restore the image to achieve fault-tolerant. Both theoretical analysis and simulation results demonstrate the effectiveness and practicality of the proposed schemes.