Research On Reversible Information Hiding Method Based On Image In Ciphertext Domain

The issue of information security is particularly important in the current open network environment.For digital images,encryption technology and information hiding technology are generally combined to ensure the security of image transmission and storage.Because the image encryption and information hiding processes restrict each other in the ciphertext domain reversible algorithm,it is difficult for the ciphertext domain image reversible information hiding algorithm to take into account the performance of security and hiding capacity.Aiming at the problem of low security of image encryption algorithms in the ciphertext domain image reversible information hiding algorithm,this paper conducts in-depth research on classic encryption algorithms such as scrambling encryption,chaotic map encryption,and exclusive-or hybrid encryption,and uses the scramblingdiffusion encryption scheme.An image encryption algorithm based on chaotic system is proposed.The pixel position of the carrier image is changed through the double reset operation of random image block reorganization and Arnold transformation.The chaotic sequence generated by logistic mapping is used as the diffusion sequence of the encryption algorithm,and DNA encoding and calculation are performed respectively to obtain the final encrypted image.Experimental results and analysis show that the encryption algorithm in this paper can resist known plaintext attacks and differential attacks.The average pixel change rate(NPCR)of the encrypted image is 99.61%,and the average uniform change intensity(UACI)average value is 33.44%,which is similar to that of the original plaintext image.The structural similarity(SSIM)approaches 0,the information entropy approaches 8,and there is almost no correlation between adjacent pixels,and the encryption algorithm has good security.Aiming at the low hiding capacity of the difference histogram translation algorithm,combined with the image interpolation method and the difference histogram translation algorithm,a completely reversible and separable ciphertext domain image reversible information hiding algorithm is proposed.The algorithm first performs recombination scrambling encoding encryption on the carrier image,performs interpolation and amplification on the encrypted image,determines the pixel value of the target interpolation image according to the pixel value of the encrypted image,and calculates the difference between the three adjacent pixel values of the target interpolation image.The difference histogram translation algorithm embeds the secret information in the interpolated image,and only one bit of the pixel value is modified in each embedding process.The embedding method is simple and effective.In order to maintain the high quality of the hidden image,only a single layer of the interpolated image is embedded.Through experiments and simulation analysis,the maximum embedding capacity of the standard 256×256 grayscale image reaches 393,216 bits,and the embedding rate is 0.67 bpp.At the same time,the PSNR of the hidden image can be maintained above 58 d B.The information extraction stage can completely separate the secret information extraction step and the decryption restoration step of the carrier image,and the carrier image can be restored completely reversibly and losslessly.