Design And Implementation Of Watermarking Algorithm For Color Code Image

With the rapid development of the mobile industry and the coming of3G era, color code as a new technology of the mobile phone recognition, Because of its greater advantages than the previous bar-code identification method it will have a wider application market. The convenience of the network may make color code in the process of network transmission be affected by the malicious copy, distribute, or tamper, the subsequent a series of issues (information security and copyright disputes) will be the solved real problem. The digital watermarking technique is commonly used technology of the copyright protection in recent years, a number of landmark information will be embedded in digital products by certain algorithm, but does not affect the value and use of original content, and the human perceptual system cannot be aware of them.The thesis, based on researching on digital watermarking technology, tries to find the right digital watermarking algorithm to solve the security issues of the color code, the major research work can be summarized as following:1. We firstly introduce the basic knowledge of the color code, such as concept, core values, technical characteristics, and applications and so on. These knowledge lay a theoretical foundation for widely application.2. We study the relative theories of the digital watermarking, including technical characteristics, classification, the basic model of the system, attack techniques, image watermarking system evaluation and typical algorithms, and further study Contourlet transform.3. Combined with Arnold scrambling technology, this thesis proposes a robust watermark algorithm based on SVD and Contourlet domain for color code image. The algorithm after performing the Contourlet transform on blue channel, approximation sub-band of blue channel is performed SVD to embed the watermark. The experimental results show that the proposed algorithm is robust and invisible and the watermarking can be extracted with small watermark embedding strength which can protect the copyright effectively.4. Combined with the Logistic map and SVD, a blind watermarking algorithm for color code image in Contourlet domain is proposed. The algorithm first convert the host image from the RGB color space to YUV color space, then performing the Contourlet transform on the luminance component Y, and approximation sub-band of Y is divided into non-overlapping4×4blocks, and finally each block is performed SVD to embed chaotic scrambling watermark information in the first singular value of each block by the rules. The experimental results show that the algorithm has better visibility and robustness, and implement blind detection.