Research On Image Encryption Algorithm Based On Chaotic Sequence

With the popularization and application of big data,network communication has become the main way of daily communication.In daily life,many images are transmitted through the network every day,therefore the image security communication technology become more and more important.The images have large data volume,strong information correlation and large redundancy,which the ordinary data encryption algorithm is not suitable for image encryption algorithm.Due to chaotic has randomness,non-periodicity and extreme sensitivity to parameter values and initial values,it has a natural advantage in the field of image encryption algorithm.Therefore,this paper uses chaotic sequence to design the image compression-encryption algorithm,and analyze the algorithm security.The following is specific research contents:A grayscale image compression-encryption algorithm by using the 3-dimensional discrete hyperchaotic sequence and compression sensing theory is designed.In this algorithm,firstly the image of sparse matrix is obtained by the discrete wavelet transform.The measurement matrix is constructed through 3-dimensional discrete hyperchaotic sequence,and the sparse representation of image is projection measured,and then the projection measurement results are scrambled operations by the improved algorithm of Arnold.Finally diffusion operation is operated through combined with 3-dimensional discrete chaotic sequence and the diffusion modulus diffusion algorithm,and get a compression-encrypted image.And the comparison results with existing algorithm ensure the effectiveness of the algorithm.A color image compression-encryption algorithm based on the 4-dimensional fractional-order chaotic sequence and compression perception is constructed.In this algorithm,firstly color image is decomposed into red(R),green(G)and blue(B)three parts,then the red,green and blue three parts are respectively sparse representation by using the discrete cosine transform,and the measurement matrix is constructed by using the fractional order chaotic sequence,and did the projection measurement.Zigzag scrambling algorithm is used to scrambling action of three component respectively,finally by using modulus left diffusion algorithm and the fractional order chaotic sequence to diffusion algorithm for three-component,then three components together,and get a compression-encrypted image.The comparison results with existing algorithm ensure the effectiveness of the algorithm.A gray image compression-encryption algorithm based on the 3-dimensional bandpass filtering fractional-order chaotic sequence and(Back-Propagation)BP neural network is designed.In this algorithm,firstly the image is divided into blocks,then using the BP neural network for the block to do the training,and Zigzag scrambling algorithm is used to scramble for compressed image.Finally image is diffused operation by xor diffusion algorithm and bandpass filtering fractional-order chaotic sequence,and then got a compression-encrypted image.And the comparison results with existing algorithm ensure the effectiveness of the algorithm.