Adaptive image encryption domain reversible hiding method based on hybrid encryption mechanism

Abstract

The invention discloses an adaptive image encryption domain reversible hiding method based on a hybrid encryption mechanism. A user performs sequential prediction on a digital image to be encrypted toobtain the pixel type identification matrix of an original image, and adaptively selects an optimal block size of the pixel type identification matrix to generate an optimal block type identificationmatrix; a random number is taken as a secret key to combine the block type identification matrix, and 'xor plus pixel classification scrambling' is used for generating an encrypted image of the original image; the random number is taken as a secret key to encrypt partial information of the block type identification matrix, the public key of a receiver uses an asymmetric encryption algorithm to encrypt 'the random number, the residual block type identification matrix information and the optimal block size', which are then serially embedded into a variable pixel of the encrypted image; the receiver uses a private key to decrypt the extracted key information and can obtain a decrypted image the same as the original image and a plaintext image with additional information through sequence recovery. The method reduces the difficulty of secret key management, improves the security of image transmission, and brings convenience for cloud management.

Description

technical field [0001] The invention relates to a method for reversible hiding of an image encryption domain. Background technique [0002] With the rapid development of cloud computing, digital image security and privacy protection have attracted widespread attention during cloud storage and transmission. The digital images uploaded by users to the cloud storage must be encrypted before uploading to realize the privacy protection of the digital image content; at the same time, the cloud needs to embed additional information in the ciphertext image to facilitate its management; at the receiving end, receivers with different permissions need to Extract hidden information or / and obtain original image data. Image encryption domain reversible information hiding (RDHEI: Reversible Data Hiding in Encrypted Image) technology can meet the above requirements of cloud services. Reversible information hiding in the image encryption domain can embed hidden information in the image enc...

AI Technical Summary

Problems solved by technology

However, due to the large amount of digital image data, the time complexity of directly encrypting the image with the public key is high, and there is serious data expansion; for example, in the algorithm of Chen et al., for each 8-bit pixel value, the pixel value expansion after homomorphic encryption to 512×4 bits

That is to say, the size of the encrypted image will be doubled, which will adversely affect the transmission and storage of encrypted data

Images