S. Aleksienė “Hiding visual information in deformable and two-dimensional moiré gratings” doctoral thesis defence

Author, Institution: Sandra Aleksienė, Kaunas University of Technology

Science area, field of science: Physical Sciences, Informatics, 09P

Scientific Supervisors:
Prof. Dr. Habil. Minvydas Kazys Ragulskis (Kaunas University of Technology, Physical Sciences, Informatics – 09P), from 2014 to 2018
Prof. Dr. Eligijus Sakalauskas (Kaunas University of Technology, Physical Sciences, Informatics – 09P), from 2013 to 2014

Dissertation Defence Board of Informatics Science Field:
Prof. Dr. Habil. Rimantas Barauskas (Kaunas University of Technology, Physical Sciences, Informatics – 09P) – chairman;
Prof. Dr. Habil. Raimondas Čiegis (Vilnius Gediminas Technical University, Physical Sciences, Informatics – 09P);
Prof. Dr. Vacius Jusas (Kaunas University of Technology, Informatics – 09P);
Prof. Dr. Habil. Genadijus Kulvietis (Vilnius Gediminas Technical University, Physical Sciences, Informatics – 09P);
Prof. Dr. Miguel A. F. Sanjuan (Rey Juan Carlos University, Physical Sciences, Informatics – 09P).

The doctoral dissertation is available at the libraries of Kaunas University of Technology (K. Donelaičio St. 20, Kaunas), Vytautas Magnus University (K. Donelaičio St. 52, Kaunas) and Vilnius Gediminas Technical University (Saulėtekio al. 14, Vilnius).

Annotation:

The aim of dissertation is to create theoretical foundations and construct appropriate algorithms that allow the modeling of optical effects of dynamic visual cryptography in deformable and two-dimensional moiré gratings. The object of the research is the development of dynamic visual cryptography-based numerical image hiding algorithms in deformable harmonic, chaotic and two-dimensional moiré gratings.
New methods of dynamic visual cryptography have been proposed in the thesis, where a deformed moiré grating oscillates harmonically and chaotically according to a certain Eigen-shape. A detailed analysis of these new methods opens the possibilities of applying the proposed methods for optical control of micro-opto-electromechanical systems.
The most important element of the scientific novelty of this dissertation is the realization of dynamic visual cryptography in two-dimensional finite element gratings. In the works known so far, the principle of dynamic visual cryptography-based image hiding was based on the formation of time-averaged moiré fringe in one-dimensional moiré gratings. Applying image coding algorithms to two-dimensional gratings greatly expands the scope of the presented algorithms that constitutes the practical value of this dissertation.