Research Of Robust Watermarking Algorithm For Digital Images On Thransform Domain

With the coming of information era,the rapid development of computer network technology,multimedia information technology and related fields,which lead to the rapid spread of digital products,digital information becomes more and more important in modern life.However,with the spread of digital products,the resulting infringement has become increasingly serious,how to effectively protect the digital the copyright owner's legitimate rights and interests,has become the digital information security problem nowadays.When facing such a situation,the digital watermarking technology appears,which can solve hot issues of multi media copyright protection.Digital watermarking by mark containing watermark information hidden in the digital multimedia works,to protect the work safety in this paper.In order to overcome the shortcomings of the original digital image watermarking for copyright protection,improve the security of digital products,by improving the count Method to balance the non sense and robustness of digital watermarking,and enhance the ability of various attacks,as well as a variety of joint attacks.The main contents and innovative points of this paper are as follows:(1)The background,development status and application of digital watermarking are systematically discussed,and the effectiveness of all kinds of algorithms are studied,which provides a theoretical basis for the realization of this algorithm.(2)In order to improve the robustness of digital image watermarking,presents a fusion of discrete cosine transform and Hamming code of digital image watermarking.The algorithm firstly uses Arnold transform and Hamming code by scrambling encryption and encoding process of the two value watermark image;then the carrier image using the block of eight plus eight,at the same time using discrete cosine transform for each sub-block;the frequency information watermarking information is embedded into the two-dimensional discrete cosine transform,the embedding strength is selected based on characteristics of carrier image.Experimental results show that the watermark shows good security and imperceptibility,which can not only prevent noise,effectively re-sampling,filtering,compression,rotation,shear and other single watermark attack,watermark attack combined on a variety of combinations of single watermark has good robustness,which get the embedding and watermark blind extraction.(3)In order to deal with the digital watermark robustness and invisibility between conflict and achieve better protection information carrier objective,this paper proposes a dwt-dct hybrid transform domain and SVD based on combined resistance to a variety of attacks of digital image zero-watermarking technology.The technology after the original image into blocks using SVD,then extract each sub-block's first singular value and the quantization process,and the final image watermarking combine to produce zero-watermark registration.Experiments show that,the technology can effectively fight against a variety of attacks and special for JPEG compression,which showed better robustness,fully embodies the practicality.