Application Of Wavelet Transform In Digital Image Watermarking Technology

The development of the Internet for the spread and application of digital media information provides a more convenient way,however,the characteristics of the digital media itself determines the copyright of digital information is more likely to be destroyed,so how to more effectively protect the copyright of digital media into a digital information technology in a problem cannot be ignored.In recent years,cryptography and digital watermarking technology research more and more hot,has made the research results has been widely applied in the field of digital media,and has obtained the remarkable effect.In the case of cryptography,digital watermarking technology can protect the copyright of digital works by embedding the copyright information with multimedia data.As digital watermarking technology as a new field of information security technology in the field of digital media applications and development of effective,relevant algorithms has become a hot research direction.This paper introduces the theory of digital watermarking technology,the common watermarking algorithm and the performance evaluation method of digital watermarking system.Then introduced the theory of wavelet transform,wavelet transform is applied in the field of digital watermarking algorithm and how to use wavelet transform to design watermarking algorithm,as well as the singular value decomposition technique,and combined with its advantages,use wavelet transform to design multiple,robust digital watermarking algorithm is proposed.Combination of bit-plane decomposition technology is a bit of watermark image are decomposed,and the binary image and common gray image as watermarking,based on human visual characteristics(HVS)to compare their effects after decomposition.The algorithm firstly in host image in the wavelet domain of the low frequency subband using block DCT,quantification of the watermark image resulting from the conversion coefficient of the watermark is embedded into the low frequency subband,at the same time in the host image of wavelet domain of the high-frequency subband using block singular value decomposition technique,embedded in the high frequency subband quantization singular value vector,on the basis of embedded after has the characteristics of medium frequency subband,using zero watermark extraction as a means of digital image copyright protection.In order to improve the robustness of the algorithm itself,this paper,by quantifying the same watermark information,is embedded into the airspace of the host image.Finally,by using Lena image and remote sensing images and video image digital watermark embedding and extraction experiments,the experimental results show that the algorithm can effectively resist from outside interference and show good robustness and concealment.