Research On Color Digital Holographic Watermarking Technology

The security of digital information is the hot topic which has been concerned. And it is a popular and difficult problem which has been widely researched now. The problem of the security in digital information's storage/ transmission and digital information's copyright protection was the focus in them.In this paper, a color digital holographic watermarking technology has been researched, combined with Computer-Generated Holography, Digital Holography and Digital Watermarking. And then, this technology was applied to the color digital images which were in the multimedia information security field.The main research work in this paper is included in the following there facets.1. The character and digital reconstruction of the CGH have been researched. Then on its basis, a coding method of the elimination of aliasing image in the digital reconstruction of Fourier CGH is presented. By expanding the space size of the original image, the Fourier-Burch's CGH is produced. It could solve the problem of aliasing image and the transformed image can be reconstructed exactly.2. The color digital holography technology has been researched. Based on the character of Fourier CGH and Fresnel CGH, the digital image's color CGH was got, which could be digital rebuilt.This is the base of the research on color digital holographic watermarking.3. The color digital holographic watermarking technology has been researched. The color CGH as watermark was embedded into the color images, which increased the protected information. Two algorithms have been proposed. One is the color digital holographic watermarking algorithm based on JPEG model. Another is the color digital holographic watermarking using wavelet transforms. Then, the color CGH watermark can be extracted clearly. Finally, the experiment results show that the tow algorithms had high security and robustness.