6 Combinational Domain Digital Watermarking
Frank Y. Shih · 2017
This chapter briefly introduces genetic algorithms (GAs). It presents the concept of GA-based watermarking and also describes the GA-based rounding error watermarking scheme. The chapter then explores the application of GA methodology to medical image watermarking. It presents authentication of JPEG images based on GAs. GAs, introduced by Hollard in his seminal work, and is commonly used as adaptive approaches to provide randomized, parallel, and global searching based on the mechanics of natural selection and natural genetics in order to find solutions to a problem. The chapter also presents the procedure of evaluating a chromosome. The purpose of crossover is to avoid a situation where the searching procedure is blocked on local minimum/maximum subsets by significantly modifying the genes of a chromosome. The purpose of mutation is to provide a local minimum/maximum searching approach by slightly modifying the gene of a chromosome. The fitness function is used to evaluate the quality of the chromosomes in the current generation.