Research On Key Technologies Of Reversible Data Hiding For JPEG Images

With the rapid development of computer and multimedia technology,network information has become an important trend of social and economic development.Huge amounts of information in government,military,cultural and educational fields are stored,transmitted and processed in cyberspace.The open network environment inevitably attracts all kinds of network attacks(such as information interception,information interception,data tampering,data forgery,etc.)from all over the world.In order to guarantee the security of network data transmission,researchers put forward a reversible data hiding algorithm,through which the sender embedds the secret information into the host signal in an imperceptible way to avoid the tracking of the attacker during transmission,so as to guarantee the security of data transmission.After the receiver receives the confidential data,Using the extraction algorithm,the secret information and carrier data can be recovered without loss.In this paper,algorithm research is carried out for multimedia image security under different application environments,and the main achievements are as follows:Scheme 1: A medical image protection algorithm based on reversible data hiding is proposed.The scheme used the coefficient of variation to locate the lesion area and set it as the key-area.Part of the information of medical image is used to generate QR code,which is covered as a visible watermark in the key-area of the image.The image segmentation scheme was designed,the mean square error of image blocks was calculated to analyze the texture complexity,and the texture region was selected as the embedded region.The histogram technique is used to hide the key-area as secret information in the selected embedded regions.This scheme can effectively hide the information of the lesion area in the image,improve the security of the key contents of the medical image,and enhance the concealment of the patient information.Scheme 2: In order to improve the performance of the above scheme,a partial encryption algorithm based on reversible data hiding and two-dimensional code is proposed by combining encryption with reversible data hiding.Firstly,the key region of the image is identified by the coefficient of variation,and then the other regions are processed and the texture complexity is analyzed.Combined with the results of texture analysis,reversible data hiding algorithm is used to embed the content of the lesion region into the high texture region,and then Arnold transform is used to encrypt the lesion information of the texture region.After that,we use the image basic information ciphertext and decryption parameters to generate a two-dimensional code to replace the original lesion area.The security of image content is further improved.Scheme 3: Based on the previous research,aiming at the characteristics of JPEG images,an improved algorithm based on the embedding capacity of JPEG images is proposed.Analysis of coefficient of discrete cosine transform,the use of correlation between DCT coefficient blocks,DCT coefficient prediction model was constructed;At the same time,the double-ranking scheme of DCT coefficient and prediction error was adopted to optimize the information embedding order.Finally,the secret information is embedded into the JPEG image using the prediction error expansion technique.Theoretical and experimental analysis show that the proposed algorithm can improve the embedding capacity of JPEG loaded images while maintaining good visual quality and small file increment of carrier images.