Research On Digital Watermarking Algorithms For Color Images

Digital watermarking is the most important branch of information hiding. Watermarking technique has gained more and more concerns since it appeared in 1993. It can provide effective protection for digital media forgery, falsification, authentication, security and intactness by embedding a special mark (digital watermark) into the multimedia data.Color is the basic element of all kinds of image. It contains a lot of information that the word and gray image cannot convey. The current applied range of digital watermarking technique is limited greatly because the gray value images are widely selected as original images. Therefore, researches in this paper mainly focus on the watermarking technologies for color images, which are described as follows:1. An effective digital watermarking algorithm for color images against co-mpression is proposed. It improves embedding and extracting principles based on Inoue's significant wavelet coefficients algorithm, and it is used in digital watermarking algorithm for color images. The experimental results demonstrate that the algorithm is robust against compression.2. An improved digital watermarking algorithm for color images based on HVS is proposed. It embeds a color digital watermark into an original color image which makes the watermarking more meaningful. The algorithm scrambles the original watermarking image in pretreatment, which improves the ability against attacks of the algorithm. The watermark is embedded in the low frequency subband, which gives us a new cognition.