Research On Reversible Data Hiding Alorithm In Encrypted Image Based On Multi-layer Prediction And Hierarchical Compressoin

With the rapid development of the mobile Internet in recent years,cloud storage technology has been widely used in the field of data storage and has become an inseparable part of people’s lives.An important part of cloud storage technology is that the cloud administrator embeds standard tags and other data in the image to manage the image stored in the cloud.Based on the need to protect the secure storage of cloud data,reversible data hiding in encrypted image has become an important research direction,and use this technology to encrypt the image and embed additional data in the encrypted image.This paper uses a special encryption technology based on multi-layer prediction errors to retain the correlation of the image,and uses run-length coding compression technology and in-block lossless compression technology to free up additional data embedding space,focusing on the security of the encrypted image,and the accuracy of the prediction method during the encryption process two reversible RDH-EI algorithms are proposed in three aspects:and additional data embedding capacity.The research content of this paper is as follows:A RDH-EI algorithm based on multi-layer prediction error and coding compression is proposed.In the encryption part of this algorithm,a special encryption technology based on calculating multi-layer prediction errors is used to preserve the correlation of the image.The prediction algorithm determines the predicted value of the pixel by comparing the average value and the minimum difference of 128.It can be applied to multiple high bits.In the plane.And use run-length coding compression technology to free up the embedding space of additional data.The experimental results show that the RDH-EI algorithm proposed in this paper can recover the embedded additional data and the original image losslessly,and the prediction algorithm proposed in this paper has higher accuracy in the special encryption process than other prediction algorithms.Compared with similar algorithms,The average value of the additional data embedding rate of the algorithm in this paper can reach 2.03bpp,which is better than similar algorithms.A RDH-EI algorithm based on hierarchical compression is proposed.Compared with the first algorithm,this algorithm is an RDH-EI algorithm that vacate room after encryption.In the encryption part of the algorithm,the image is encrypted using the special encryption algorithm based on the multi-layer prediction error and the mod256 encryption algorithm in the previous algorithm,which successfully preserves the pixel correlation within the image block while ensuring the security of the encrypted image.In the additional data embedding part,a new hierarchical compression technology is proposed to label and compress the selected pixel block.When the selected pixel block is a complex block,the pixel block will be divided into three different types and labeled and compressed.Compression frees up space in the pixel block where additional data can be embedded.The experimental results show that this algorithm can recover the embedded additional data and the original image losslessly.When the block length S=4 is selected,the optimal embedding capacity of this algorithm can be achieved.Compared with similar algorithms,this algorithm performs better.