Research On Digital Watermarking Algorithm Based On Chaotic Property

The digital image watermarking algorithms are investigated based on the chaos systems. Firstly,performances of multiple chaos systems are analyzed and compared with each other, Secondly,the binary sequences of the chaotic systems are generated and the randomness and relevance of the binary sequences are analyzed.The binary sequences generated by the Qi chaotic system have good randomness and relevance.At the meantime,a watermarking algorithm based on the Fourier transform is presented here,in which watermarks are preprocessed with the chaos arrays,and then the existence of watermarks is detected by correlation-detecting methods;Another watermarking algorithm is proposed based on the wavelet transform.In this algorithm,watermarks are embedded self-adaptively by texture coding of the images,and the preprocessed watermarks will then be embedded into high frequency bandwidth field.Experimental results show that by testing on multiple images, these two algorithms are with good robustness.And moreover,applying the bi-value arrays into the preprocessing of watermarks has greatly enhanced the safety of watermarking algorithms.