2012年5月9日下午，台湾逢甲大学张真诚教授访问重点实验室。张教授现任逢甲大学何宜武先生学术讲座教授，中正大学荣誉教授、合聘教授与清华大学合聘教授。张教授在成功楼603做了题为“Information Steganography Using Magic Matrix”的报告，围绕着信息隐藏的攻和防的问题，与实验室研究人员展开了讨论；张教授的学术报告和回答深入浅出，生动直观，获得了听众的热情回应，报告会始终气氛活跃；张教授最后鼓励和欢迎优秀的博士和研究生到台湾高校进行学术交流和进修。

报告摘要:

      Steganography is the science of secret message delivery using cover media.  A digital image is a flexible medium used to carry a secret message because the  slight modification of a cover image is hard to distinguish by human eyes.

      In this talk, I will introduce four methods: VQ encoding method, Kim et  al.'s method, Zhang and Wang’s method and Sudoku solutions. A selected Sudoku  solution is used to guide cover pixels’ modification in order to imply secret  data. Because the number of possible Sudoku solutions is very large, the  proposed method is more secure than Kim et al.'s method and Zhang and Wang’s  method. From the experimental results, the visual quality of stego images  produced by the Sudoku method is higher than 44 dB in average, which is  slightly less than that of related works; however, the embedding capacity of  the proposed method is 1.5 bit per pixel, which is greater than that of the  related works.

专家介绍 ：

       Professor C. C. Chang was born in Taichung, Taiwan. He obtained his Ph.D. degree in computer engineering from National Chiao Tung University. His first degree is Bachelor of Science in Applied Mathematics and master degree is Master of Science in Computer and Decision Sciences. Both were awarded in National Tsing Hua University. Dr. Chang served in National Chung Cheng University from 1989 to 2005. His current title is Chair Professor in Department of Information Engineering and Computer Science, Feng Chia University, from Feb. 2005. Prior to joining Feng Chia University, Professor Chang was an associate professor in Chiao Tung University, professor in National Chung Hsing University, chair professor in National Chung Cheng University. He had also been Visiting Researcher and Visiting Scientist to Tokyo University and Kyoto University, Japan. During his service in Chung Cheng, Professor Chang served as Chairman of the Institute of Computer Science and Information Engineering, Dean of College of Engineering, Provost and then Acting President of Chung Cheng University and Director of Advisory Office in Ministry of Education, Taiwan.      

             Professor Chang’s specialties include, but not limited to, data engineering, database systems, and computer cryptography and information security. A researcher of acclaimed and distinguished services and contributions to his country and advancing human knowledge in the field of information science, Professor Chang has won many research awards and honorary positions by and in prestigious organizations both nationally and internationally. He is currently a Fellow of IEEE and a Fellow of IEE, UK. And since his early years of career development, he consecutively won Outstanding Youth Award of the R. O. C., Outstanding Talent in Information Sciences of the R. O. C., AceR Dragon Award of the Ten Most Outstanding Talents, Outstanding Scholar Award of the R. O. C., Outstanding Engineering Professor Award of the R. O. C., Chung-Shan Academic Publication Awards, Distinguished Research Awards of National Science Council of the R. O. C., Outstanding Scholarly Contribution Award of the International Institute for Advanced Studies in Systems Research and Cybernetics, Top Fifteen Scholars in Systems and Software Engineering of the Journal of Systems and Software, and so on. On numerous occasions, he was invited to serve as Visiting Professor, Chair Professor, Honorary Professor, Honorary Director, Honorary Chairman, Distinguished Alumnus, Distinguished Researcher, Research Fellow by universities and research institutes. He also published over 1300 papers in Information Sciences. In the meantime, he participates actively in international academic organizations and performs advisory work to government agencies and academic organizations.