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http://hdl.handle.net/10012/1126
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| Title: | Grey Level Visual Cryptography for General Access Structures |
| Authors: | MacPherson, Lesley |
| Keywords: | Computer Science
visual cryptography
secret sharing
cryptography |
| Approved Date: | 2002 |
| Date Submitted: | 2002 |
| Abstract: | Visual cryptography, first introduced by Naor and Shamir, allows a secret (black and white) image to be encoded and distributed to a set of participants such that certain predefined sets of participants may reconstruct the image without any computation. In 2000, Blundo, De Santis, and Naor introduced a model for grey-level visual cryptography which is a generalization of visual cryptography for general access structures. Grey-level visual cryptography extends this model to include grey-scale images. Decoding is done by the human visual system. In this thesis we survey known results of grey-level visual cryptography and visual cryptography for general access structures. We extend several visual cryptography constructions to grey-level visual cryptography, and derive new results on the minimum possible pixel expansion for all possible access structures on at most four participants. |
| Department: | School of Computer Science |
| Degree: | Master of Mathematics |
| URI: | http://hdl.handle.net/10012/1126 |
| Appears in Collections: | Electronic Theses and Dissertations (UW)
Faculty of Mathematics Theses and Dissertations
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