Reversible data hiding method for high-capacity ciphertext domain image

Abstract

The invention discloses a high-capacity ciphertext domain image reversible data hiding method. The method comprises the steps of binary position map generation, image encryption, ciphertext domain image reversible data hiding, secret information extraction and original image lossless recovery. According to the first part, adjacent pixels are used for predicting a current pixel value, all pixel points in an image are divided into a prediction error type and a prediction accuracy type according to the difference of prediction values, and a binary position map is used for marking; a second part of encrypting the grayscale image by using a binary pseudo-random sequence generated by an encryption key; in the third part, a binary pseudorandom sequence generated by a data hiding key is used for encrypting the hidden information, and three-layer MSB replacement is carried out on pixel points marked as accurate prediction in the ciphertext domain image according to a binary position map so as to complete data embedding; in the fourth part, the original image can be recovered in a lossless manner by using the encryption key, and the secret information can be accurately extracted by using thedigital hidden key; the method has the advantages that information is embedded into three layers of MSB bits of the ciphertext domain image, and the embedding capacity is high.

Description

technical field [0001] The invention relates to a ciphertext domain data hiding technology, in particular to a high-capacity ciphertext domain image reversible data hiding method. Background technique [0002] With the development of the mobile Internet and the popularization of smart terminals, digital images have exploded. Cloud computing provides an effective solution for the storage and processing of massive digital images. However, the structural characteristics of the cloud computing environment itself also bring great hidden dangers to privacy security. Attackers may bypass the authentication mechanism of the cloud platform and obtain user data by directly accessing lower-level files or original data. One of the best ways to ensure the privacy and security of digital images is to encrypt them. Users first encrypt sensitive content before uploading. All processing and calculations in the cloud are performed in the ciphertext domain, and the processing results are pro...

AI Technical Summary

Problems solved by technology

Under this background, reversible data hiding in ciphertext domain came into being. The existing reversible data hiding technology in ciphertext domain can be divided into three categories: the first category is to encrypt the image and find the data embedding space. This kind of method generally embeds the capacity The second type is to reserve data embedding space before image encryption. This type of method has a large embedding capacity and low distortion, but the disadvantage is that a complex protocol is required between the image encryptor and the data embedder; The third category is to use homomorphic encryption to realize reversible data hiding in ciphertext domain images, but homomorphic encryption can easily cause ciphertext data expansion

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