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The typical model of steganography has led the prisoners' problem, in which two persons attempt to communicate covertly without alerting the warden. The general way to achieve this task is to embed the message in an innocuous-looking medium. In this paper, an object-based geometric embedding technique is proposed for solving the prisoners' problem. The main idea is to embed secret data through distorting a given object and the distorted object still looks natural. In the embedding process, the secret message is first converted into coefficients of an affine transformation. Then, the coordinates of each pixel of a selected object in the cover-image are recomputed by this affine transformation. Since these coefficients are restricted in a specific range, the transformed object looks natural. In the extracting process, a coarse-to-fine iterative search is proposed to accelerate the object location and the message extraction. Experimental results show that all transformed objects can be located precisely and the whole hidden message can be extracted correctly even if the stego-image is stored in various compression formats and rates. Furthermore, the embedded message is robust enough when the stego-image format is converted from GIF to JPEG, and vice versa.

The typical model of steganography has led the prisoners' problem, in which two persons attempt to communicate covertly without alerting the warden, that is, only the receiver knows the existence of the message sent by the sender. One available way to achieve this task is to embed the message in an innocuous-looking medium. In this paper, we propose a variation of the Quantization Index Modulation (QIM) for solving the prisoners' problem. We also propose a theorem to show that the error of mean intensity value of an image block caused by JPEG compression is bounded. The proposed method embeds the messages to be conveyed by modifying the mean intensity value, and the resulting stego-image can be stored in the JPEG format with a low quality setting. Besides, a specific pattern caused by using the QIM embedding method is also identified, and this pattern will be removed using the proposed embedding method. Experimental results and the proposed theorem show that the hidden message is error-free against the JPEG distortion under the quality setting as low as 25. Furthermore, the existence of the hidden message is not only visually imperceptible but also statistically undetectable.

Aiming at resolving the conflict between security and efficiency in the design of chaotic image encryption algorithms, an image encryption algorithm based on information hiding is proposed based on the “one-time pad” idea. A random parameter is introduced to ensure a different keystream for each encryption, which has the characteristics of “one-time pad”, improving the security of the algorithm rapidly without significant increase in algorithm complexity. The random parameter is embedded into the ciphered image with information hiding technology, which avoids negotiation for its transport and makes the application of the algorithm easier. Algorithm analysis and experiments show that the algorithm is secure against chosen plaintext attack, differential attack and divide-and-conquer attack, and has good statistical properties in ciphered images.

We propose an inference prevention agent as a tool that enables each of the databases in a distributed system to keep track of probabilistic dependencies with other databases and then use that information to help preserve the confidentiality of sensitive data. This is accomplished with minimal sacrifice of the performance and survivability gains that are associated with distributed database systems.

We investigate the possibility of having someone carry out the work of executing a function for you, but without letting him learn anything about your input. Say Alice wants Bob to compute some known function f upon her input x, but wants to prevent Bob from learning anything about x. The situation arises for instance if client Alice has limited computational resources in comparison with mistrusted server Bob, or if x is an inherently mobile piece of data. Could there be a protocol whereby Bob is forced to compute ,f(x)blindly, i.e. without observing x? We provide such a blind computation protocol for the class of functions which admit an efficient procedure to generate random input–output pairs, e.g. factorization. The cheat-sensitive security achieved relies only upon quantum theory being true. The security analysis carried out assumes the eavesdropper performs individual attacks.

At present, capacity is the prevailing paradigm for covert channels and most of current researches are based on Shannon’s channel theory. With respect to steganography, however, capacity is insufficient. Ira S. Moskowitz et al propose “capability” paradigm in [1], but they had not given a feasible algorithm for “capability” description. In this paper, a new capability description for audio information hiding is proposed and a feasible mathematic method is given to determine how much information can be hiding. The proposed capability description can be used to give a prediction framework of steganographic communication in our speech steganography system.

The study on human visual system points out that modification on wavelet high frequency subband coefficients is hard to be perceived by human eyes. Network security technology is benefit to information security transmission. The paper put forward a security transmission framework that utilize discrete wavelet transform to transmit secrete data (such as password, etc) carried by common picture in application layer and utilize VPN gateway based on the IPSec tunnel protocol to encapsulate IP packet in network layer. It provides a kind of new choice for end-to-end security transmission.

This paper puts forwards the detecting algorithm and the extracting algorithm for hidden information, which are respectively based on domain of variation and still color digital image. Efforts are made to explore the effects of the amplified information of wavelet transformation, the displaying of hidden information and its opposite process. Based on the model of the influence of information hiding on carrier properties, this paper establishes a general mathematical model for extracting hidden information and a positive transfer function and a reverse transfer function oriented to the set of “the influence of information hiding on carrier properties”. After the information is marked, analyzed and extracted, the hidden information can be restored, with satisfactory results for information recognition and analysis. As a result, it is possible to extract electronic evidence of hidden data rapidly.

Based on wavelet transforms, an algorithm is proposed to scramble digital images. The algorithm changes both the location and the grey grade of image points. As a result, it achieves good scrambling effects and information security. When embedding digital watermarks, the fusion factors are adjusted to maximize fusion intensity using the critical threshold of human eyes for just noticeable difference (JND). Numerical experiments show good information hiding effects and high attack resistance of the hidden images, especially the ability to resist JPEG compression. The proposed algorithm can be used to protect the copyrights of digital images, and network transmission of encrypted hidden information.

The paper proposes a music copyright protection platform. It provides services of information hiding and extracting in the form of audio digital watermarking. The information hiding algorithms of this system are designed by combining wavelet transform, data scrambling and data fusion techniques, and encapsulated.