Digital watermarking for image data

Abstract

In the past decades, the field of digital watermarking for copyright protection of different multimedia data has gained widespread popularity as research topics. Digital watermarking is a technique to embed some security messages into the multimedia data by slightly modifying the data. Those security messages can be text or image. In this project, the security analysis of different digital watermark embedding and extraction methods is firstly done. In most of the existing methods, it is found that even if we do not have correct key, the embedded content can be easily obtained. Traditionally, to solve this problem, some extra operations like bit relocation can be applied. However, this will introduce problems such as extra storage needed. We will focus on the scalar quantization based method and try to increase the robustness by increasing the number of lookup tables and interval decision.