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Twisted Ate pairing on hyperelliptic curves and applications

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science China(information sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1,2.1 school of information {2. and technology, sun yat-sen university, guangzhou 5102.5, China 2.Guangdong Key Laboratory of information Security technology, guangzhou 5102.5, China 1. school of information {2. and technology Sun Yat-Sen University Guangzhou 510275 China2. Guangdong Key Laboratory of Information Security Technology Guangzhou 510275 China

In this paper we show that the twisted Ate pairing on elliptic curves can be generalized to hyperelliptic curves, and give a series of variations of the hyperelliptic Ate and twisted Ate pairings. Using the hyperelliptic Ate pairing and twisted Ate pairing, we propose a new approach to speeding up the Weil pairing computation. For some hyperelliptic curves with high degree twist, computing Weil pairing by our approach may be faster than Tate pairing, Ate pairing, and all other known pairings.

关键词： Ate pairing Weil pairing hyperelliptic curves pairing-based cryptosystems twisted curves

Calibration based universal JPEG steganalysis

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science in China(Series F) 2009年第2期52卷 260-268页

作者： HUANG FangJun1,2.& HUANG JiWu1,2.1 school of information {2. and technology,sun yat-sen university,guangzhou 5102.5,China 2.Guangdong Key Lab. of information Security technology,sun yat-sen university,guangzhou 5102.5,China school of information {2. and technology Sun Yat-Sen University Guangzhou 510275 China Guangdong Key Lab. of information Security technology Sun Yat-Sen University Guangzhou 510275 China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

Steganalysis of stochastic modulation steganography

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science in China(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2.& HUANG Jiwu1,2.1. school of information {2. and technology, sun yat-sen university, guangzhou 5102.5, China 2. Guangdong Province Key Laboratory of information Security, guangzhou 5102.5, China 1. school of information {2. and technology Sun Yat-sen University Guangzhou 510275 China 2. Guangdong Province Key Laboratory of information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

Robust AVS audio watermarking

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science China(information sciences) 2010年第3期53卷 607-618页

作者： WANG Yong & HUANG JiWu Guangdong Key Laboratory of information Security technology, {2. of information science and technology, sun yat-sen university, guangzhou 5102.5, China 1. Guangdong Key Laboratory of information Security technology School of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China

Part Ⅲ of AVS (China Audio and Video Coding Standard) is the first generic audio standard proposed in China and is becoming popular in some applications. For MP3 audio, some effiorts have been made to solve the copyright pirating and malicious modifications by the way of watermarking. To our best knowledge, similar work on the AVS audio has not been explored. In this paper, we present a novel robust watermarking algorithm for AVS audio. We find that the frame type in the AVS coded process can be used as a robust feature for watermarking. Then we design a novel watermarking algorithm which is integrated into the AVS audio coding process. The watermark bits are embedded into the compressed bit stream. At the extracting end, the watermark bits can be extracted from the compressed bit stream directly. This algorithm achieves robustness to decoding/re-coding attacks, and has low computation complexity for both embedding and extracting while preserving the quality of the audio signals.

关键词： AVS audio security problems robust watermarking

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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science China(information sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1,DAI XianHua 2.& Pan DaRu 1 1 school of Physics and Telecommunication Engineering,South China Normal university,{2. 510006,China 2.Department of information science and technology,sun yat-sen university,{2. 51002.,China 1. school of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

Secure multi-party computation protocol for sequencing problem

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science China(information sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1,2.SHI GuiHua 1 & YAO ZhengAn 3 1 school of Mathematics and information {2.,guangzhou university,guangzhou 510006, China 2.tate Key Laboratory of information Security, Institute of Software {2.,Chinese Academy of {2.s,Beijing 100080,China 3 school of Mathematics and Computational {2.,sun yat-sen university,{12.,China 1. school of Mathematics and information {2. Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1)/2.participants, and an active adversary that can corrupt at most t 3 *** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

Perceptual video hashing robust against geometric distortions

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science China(information sciences) 2012年第7期55卷 1520-1527页

作者： XIANG ShiJun 1,4 ,YANG JianQuan 2.& HUANG JiWu 3 1 school of information {2. and technology,Jinan university,guangzhou 510632.China 2.Shenzhen Institutes of Advanced technology,Chinese Academy of {2.s,Shenzhen 518055,China 3 school of information science and technology,sun yat-sen university,guangzhou 5102.5,China 4 State Key Laboratory of information Security,Institute of Software,Chinese Academy of {2.s,Beijing 100049,China 1. school of information {2. and technology Jinan University Guangzhou 510632 China4. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100049 China2. Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China3. School of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China

In this paper,we propose a robust perceptual hashing algorithm by using video luminance histogram in *** underlying robustness principles are based on three main aspects:1) Since the histogram is independent of position of a pixel,the algorithm is resistant to geometric deformations; 2. the hash is extracted from the spatial Gaussian-filtering low-frequency component for those common video processing operations such as noise corruption,low-pass filtering,lossy compression,etc.; 3) a temporal Gaussian-filtering operation is designed so that the hash is resistant to temporal desynchronization operations,such as frame rate change and *** a result,the hash function is robust to common geometric distortions and video processing *** results show that the proposed hashing strategy can provide satisfactory robustness and uniqueness.

关键词： video hashing geometric distortion histogram Gaussian filtering

A distribution space for Hilbert transform and its applications

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science China Mathematics 2008年第12期51卷 2217-2230页

作者： YANG LiHua school of Mathematics and Computing science, {2., guangzhou 5102.5, China school of Mathematics and Computing science Sun Yat-Sen University Guangzhou 510275 China

In this paper, a new distribution space is constructed and the definition of the classical Hilbert transform is extended to it. It is shown that is the biggest subspace of on which the extended Hilbert transform is a homeomorphism and both the classical Hilbert transform for L p functions and the circular Hilbert transform for periodic functions are special cases of the extension. Some characterizations of the space are given and a class of useful nonlinear phase signals is shown to be in . Finally, the applications of the extended Hilbert transform are discussed.

关键词： Hilbert transform distribution time-frequency analysis 44A15 46F12

A Deniable Authenticated Key Agreement Protocol

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Wuhan university Journal of Natural sciences 2008年第6期13卷 645-650页

作者： TIAN Haibo1,2. CHEN Xiaofeng1,2. ZHANG Fangguo1,2. WEI Baodian1,2.1. school of information {2. and technology, sun yat-sen university, guangzhou 510006, Guangdong, China 2. Guangdong Key Laboratory of information Security technology, sun yat-sen university, guangzhou 5102.5, Guangdong, China school of information {2. and technology Sun Yat-Sen University Guangzhou 510006 Guangdong China Guangdong Key Laboratory of information Security technology Sun Yat-Sen University Guangzhou 510275 Guangdong China

This paper presents a deniable authenticated key agreement protocol. This protocol can provide an authenticated session key while the sender and the receiver can deny their involvement in such a protocol if the protocol is executed successfully. Then both can deny their transmitted messages protected by the authenticated session key. If this protocol fails, no authenticated session key can be established and no protected messages can be transmitted. The protocol can be proved secure against key compromise impersonation attack. The protocol employs a new method to isolate a session key from confirmation keys.

关键词： deniable authentication key agreement key compromise impersonation