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Ou B.,Beijing Jiaotong University | Ou B.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Li X.,Beijing Institute of Technology | Zhao Y.,Beijing Jiaotong University | And 4 more authors.
IEEE Transactions on Image Processing | Year: 2013

In prediction-error expansion (PEE) based reversible data hiding, better exploiting image redundancy usually leads to a superior performance. However, the correlations among prediction-errors are not considered and utilized in current PEE based methods. Specifically, in PEE, the prediction-errors are modified individually in data embedding. In this paper, to better exploit these correlations, instead of utilizing prediction-errors individually, we propose to consider every two adjacent prediction-errors jointly to generate a sequence consisting of prediction-error pairs. Then, based on the sequence and the resulting 2D prediction-error histogram, a more efficient embedding strategy, namely, pairwise PEE, can be designed to achieve an improved performance. The superiority of our method is verified through extensive experiments. © 1992-2012 IEEE.


Cao G.,Beijing Jiaotong University | Cao G.,Communication University of China | Zhao Y.,Beijing Jiaotong University | Zhao Y.,State Key Laboratory of Rail Traffic Control and Safety | And 3 more authors.
IEEE Transactions on Information Forensics and Security | Year: 2014

As a retouching manipulation, contrast enhancement is typically used to adjust the global brightness and contrast of digital images. Malicious users may also perform contrast enhancement locally for creating a realistic composite image. As such it is significant to detect contrast enhancement blindly for verifying the originality and authenticity of the digital images. In this paper, we propose two novel algorithms to detect the contrast enhancement involved manipulations in digital images. First, we focus on the detection of global contrast enhancement applied to the previously JPEG-compressed images, which are widespread in real applications. The histogram peak/gap artifacts incurred by the JPEG compression and pixel value mappings are analyzed theoretically, and distinguished by identifying the zero-height gap fingerprints. Second, we propose to identify the composite image created by enforcing contrast adjustment on either one or both source regions. The positions of detected blockwise peak/gap bins are clustered for recognizing the contrast enhancement mappings applied to different source regions. The consistency between regional artifacts is checked for discovering the image forgeries and locating the composition boundary. Extensive experiments have verified the effectiveness and efficacy of the proposed techniques. © 2005-2012 IEEE.


Zhang S.,Beijing Jiaotong University | Zhang S.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Liang M.-G.,Beijing Jiaotong University | Liang M.-G.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Li H.-J.,Central University of Finance and Economics
Canadian Journal of Physics | Year: 2014

The study of traffic dynamics on multilayered networks is a hot issue, where the network topology is composed of two layers of subnetworks, such as wired-wireless networks and peer-to-peer networks. Virtual links on the logical layer can be changed or constructed easily, and therefore the topological structure of the upper logical layer can be efficiently constructed by a link removal strategy. In this paper, edges linking to nodes with large betweenness will be removed. The structure of the upper-layer network can be optimized freely based on our method. Simulation results show that for both shortest path routing strategy and efficient routing strategy, the traffic capacity of two-layer networks is significantly improved. In addition, the average transmission time of packets and the average path length are also investigated in this paper. © 2014 Published by NRC Research Press.


An W.,Beijing Jiaotong University | An W.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Liang M.,Beijing Jiaotong University | Liang M.,Beijing Key Laboratory of Advanced Information Science and Network Technology
Neurocomputing | Year: 2013

Support vector machine (SVM) is a popular machine learning technique, and it has been widely applied in many real-world applications. Since SVM is sensitive to outliers or noises in the dataset, Fuzzy SVM (FSVM) has been proposed. Like SVM, it still aims at finding an optimal hyperplane that can separate two classes with the maximal margin. The only difference is that fuzzy membership is assigned to each training point based on its importance, which makes it less sensitive to outliers or noises to some extent. However, FSVM ignores an important prior knowledge, the within-class structure. In this paper, we propose a new classification algorithm-FSVM with minimum within-class scatter (WCS-FSVM), which incorporates minimum within-class scatter in Fisher Discriminant Analysis (FDA) into FSVM. The main idea is that an optimal hyperplane is found such that the margin is maximized while the within-class scatter is kept as small as possible. In addition, we propose a new fuzzy membership function for WCS-FSVM. Experiments on six benchmarking datasets and four artificial datasets show that our proposed WCS-FSVM algorithm can not only improve the classification accuracy and generalization ability but also handle the classification problems with outliers or noises more effectively. © 2013 Elsevier B.V.


Cao G.,Beijing Jiaotong University | Cao G.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Zhao Y.,Beijing Jiaotong University | Zhao Y.,Beijing Key Laboratory of Advanced Information Science and Network Technology | And 3 more authors.
IEEE Signal Processing Letters | Year: 2011

In this letter, we propose a new method in detecting unsharp masking (USM) sharpening operation in digital images. Overshoot artifacts are found to occur around side-planar edges in the sharpened images. Such artifacts, measured by a sharpening detector, can serve as a rather unique feature for identifying the previous performance of sharpening operation. Test results on photograph images with regard to various sharpening operators show the effectiveness of our proposed method. © 2006 IEEE.


Jiang Z.-Y.,Beijing Jiaotong University | Jiang Z.-Y.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Liang M.-G.,Beijing Jiaotong University | Liang M.-G.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Wu J.-J.,Hong Kong Polytechnic University
PLoS ONE | Year: 2013

Packets transmitting in real communication networks such as the Internet can be classified as time-sensitive or time-insensitive. To better support the real-time and time-insensitive applications, we propose a two-level flow traffic model in which packets are labeled as level-1 or level-2, and those with level-1 have higher priority to be transmitted. In order to enhance the traffic capacity of the two-level flow traffic model, we expand the global dynamic routing strategy and propose a new dynamic source routing which supports no routing-flaps, high traffic capacity, and diverse traffic flows. As shown in this paper, the proposed dynamic source routing can significantly enhance the traffic capacity and quality of time-sensitive applications compared with the global shortest path routing strategy. © 2013 Jiang et al.


Xiao J.,University of Liverpool | Xiao J.,Xi'an Jiaotong - Liverpool University | Tillo T.,Xi'an Jiaotong - Liverpool University | Zhao Y.,Beijing Jiaotong University | Zhao Y.,Beijing Key Laboratory of Advanced Information Science and Network Technology
IEEE Transactions on Circuits and Systems for Video Technology | Year: 2013

Forward error correction (FEC) codes are widely studied to protect streamed video over unreliable networks. Typically, enlarging the FEC coding block size can improve the error correction performance. For video streaming applications, this could be implemented by grouping more than one video frame into one FEC coding block. However, in this case, it leads to decoding delay, which is not tolerable for real-time video streaming applications. In this paper, to solve this dilemma, a real-time video streaming scheme using randomized expanding Reed-Solomon (RS) code is proposed. In this scheme, the RS coding block includes not only the video packets of the current frame, but could also include all the video packets of previous frames in the current group of pictures. At the decoding side, the parity-check equations of the current frame are jointly solved with all the parity-check equations of the previous frames. Since video packets of the following frames are not encompassed in the RS coding block, no delay will be caused for waiting for the video or parity packets of the following frames both at encoding and decoding sides. Experimental results show that the proposed scheme outperforms other real-time error resilient video streaming approaches significantly, specifically, for the Foreman sequence, the proposed scheme could provide 1.5 dB average gain over the state-of-the-art approach for 10% i.i.d. packet loss rate, whereas for the burst loss case, the average gain is more than 3 dB.MATLAB code of this paper is available for download at http://www.mmtlab.com. © 2013 IEEE.


Mu M.,Beijing Jiaotong University | Mu M.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Ruan Q.,Beijing Jiaotong University | Ruan Q.,Beijing Key Laboratory of Advanced Information Science and Network Technology | And 2 more authors.
Neurocomputing | Year: 2011

In this paper, a novel feature extraction framework is presented for palmprint identification, which provides a shiftable and gray scale invariant description of image achieving high identification accuracy at a low computational cost. The image is firstly decomposed by the shiftable complex directional filter bank (CDFB) transform which provides a two-dimensional (2-D) decomposition of energy shiftable and scalable multiresolution, arbitrarily directional resolution, low redundant ratio, and efficient implementation. Further, the subband coefficients of CDFB decomposition are operated by the uniform local binary pattern (LBP) which is gray scale invariant and contains information about the distribution of the local micro-patterns. The resulting LBP mappings are divided into many subblocks, over which the statistical histograms are achieved independently. Finally, a Fisher linear discriminant (FLD) classifier is learned in the statistical histogram feature space for palmprint identification. Experiments are executed over the HongKong PolyU palmprint database of 7752 images. To verify the high performance of our proposed feature descriptor, several other multiresolution and multidirectional transforms are also investigated including Gabor filter, dual-tree complex wavelet and Contourlet transforms. The experimental results demonstrate that CDFB yields the most promising performance balancing the identification accuracy, storage requirement and computational complexity for our proposed feature extraction framework. © 2011 Elsevier B.V.


Jiang Z.-Y.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Liang M.-G.,Beijing Jiaotong University
Physica A: Statistical Mechanics and its Applications | Year: 2013

The most important function of a network is for transporting traffic. Due to the low traffic capacity of network systems under the global shortest path routing, plenty of heuristic routing strategies are emerging. In this paper, we propose a heuristic routing strategy called the incremental routing algorithm to improve the traffic capacity of complex networks. We divide the routing process into N(the network size) steps and, at each step, we heuristically calculate all the routes for one source node considering both the dynamic efficient betweenness centrality and node degree information. We do extensive simulations on scale-free networks to confirm the effectiveness of the proposed incremental routing strategy. The simulation results show that the traffic capacity has been enhanced by a substantial factor at the expense of a slight lengthening in the average path. © 2013 Elsevier B.V. All rights reserved.


Jiang Z.-Y.,Beijing Jiaotong University | Jiang Z.-Y.,Beijing Key Laboratory of Advanced Information Science and Network Technology | Liang M.-G.,Beijing Jiaotong University | Liang M.-G.,Beijing Key Laboratory of Advanced Information Science and Network Technology | And 3 more authors.
Physica A: Statistical Mechanics and its Applications | Year: 2013

Traffic capacity of one network strongly depends on the link's bandwidth allocation strategy. In previous bandwidth allocation mechanisms, once one link's bandwidth is allocated, it will be fixed throughout the overall traffic transmission process. However, the traffic load of every link changes from time to time. In this paper, with finite total bandwidth resource of the network, we propose to dynamically allocate the total bandwidth resource in which each link's bandwidth is proportional to the queue length of the output buffer of the link per time step. With plenty of data packets in the network, the traffic handling ability of all links of the network achieves full utilization. The theoretical analysis and the extensive simulation results on complex networks are consistent. This work is valuable for network service providers to improve network performance or to do reasonable network design efficiently. © 2012 Elsevier B.V. All rights reserved.

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