The Information Hiding、Tamper Detection And Recovery Based On Gray-image

With the accelerating pace of modern society, the computer network entered aperiod of rapid development, has become the main channel for the exchange ofinformation in people’s daily lives. However, the transfer of information on the Webis still facing a lot of security issues, but also caused considerable losses to thenational economy. Therefore make full use of network facilities at the same time, wehave to consider the problems which may occur in the network transmission andstrengthen the security of network transmission.The encryption of the information is an effective method to strengthen thesecurity before transmitting it, for information receiver, only the correct key canobtain the necessary information successfully. However there are two aspects of theshortcomings of this method in information transmission.on the one hand, if the datafile is encrypted into ciphertext, it becomes incomprehensible documents and greatlyimpede the dissemination and exchange of information; on the other hand, encryptioninformation is likely to arouse doubt by network monitoring. So seeking another wayof information transfer becomes necessary.The information hiding came into being, which includes digital watermarkingand steganography. The digital watermark is used for copyright protection, broadcastmonitoring and transaction tracking. Steganographic technique is used for thetransmission of secret information. Both of which are transmit information byembedding it into digital media. In recent years, information hiding technology isbeing rapidly developed, and plays a more and more important role in the field ofinformation security.In this paper, information hidden, tamper detection and recovery which based ongray images were studied. The attributions of this paper include the following twoaspects:1. A method of embedding information in the edges of image based on edgegradient is proposed. Information is embedding on the edges of the image, flat area ofthe image without any modification, thus increase the difficulty of detecting.2. A method of tamper detection and recovery based on gray images is proposed.Mainly embed information by multi-layer. Firstly, hiding the binary image intohalftone image, and then halftone image is embedded into the gray image. For such method, the rate of detection of the tampering detection and restore the effect of theimage can be improved greatly.