Visual Cryptography & Some New Schemes using Combinatorial Designs

Speaker:          Prof. Bimal Roy   
                  Indian Statistical Institute   

Title:            Visual Cryptography & Some New Schemes 
                  using Combinatorial Designs 

Date:             Monday, 20 October 2003 

Time:             4:00pm - 5:00pm 

Venure:           Lecture Theatre F (Leung Yat Seng Lecture Theatre) 
                  (near lift nos. 25/26)   


ABSTRACT: 

For visual cryptographic schemes two parameters are very important viz. 
pixel expansion and contrast. Optimizing both seems to be a very hard 
problem. The schemes having optimal contrast tend to use a high pixel 
expansion. The focus of this talk is the construction of schemes for 
which pixel expansion is modest and the contrast is close to optimality. 
Here the tool is combinatorial designs that haven't been used earlier for 
this purpose.


BIOGRAPHY: 

Professor Bimal Roy received B.Stat. (Hons.) & M.Stat. degrees from 
Indian Statistical Institute, Calcutta, India and Ph.D. degree from 
University of Waterloo, Canada.

He is currently a professor at the Indian Statistical Institute, 
Calcutta, India. He was Assistant Professor & Visiting Associate 
Professor at the dept. of Computer Science, State University of 
New York, Institute of Technology, Utica, New York, USA. He also 
held visiting positions at Carleton University, Canada, University 
of Waterloo, Canada, Lund University, Sweden, North Carolina State 
University.

His research areas include cryptology, combinatorics, and statistics.