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A HEVC Video Steganalysis Method Using the Optimality of Motion Vector Prediction
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作者 Jun Li Minqing Zhang +2 位作者 Ke Niu Yingnan Zhang Xiaoyuan Yang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2085-2103,共19页
Among steganalysis techniques,detection against MV(motion vector)domain-based video steganography in the HEVC(High Efficiency Video Coding)standard remains a challenging issue.For the purpose of improving the detectio... Among steganalysis techniques,detection against MV(motion vector)domain-based video steganography in the HEVC(High Efficiency Video Coding)standard remains a challenging issue.For the purpose of improving the detection performance,this paper proposes a steganalysis method that can perfectly detectMV-based steganography in HEVC.Firstly,we define the local optimality of MVP(Motion Vector Prediction)based on the technology of AMVP(Advanced Motion Vector Prediction).Secondly,we analyze that in HEVC video,message embedding either usingMVP index orMVD(Motion Vector Difference)may destroy the above optimality of MVP.And then,we define the optimal rate of MVP as a steganalysis feature.Finally,we conduct steganalysis detection experiments on two general datasets for three popular steganographymethods and compare the performance with four state-ofthe-art steganalysis methods.The experimental results demonstrate the effectiveness of the proposed feature set.Furthermore,our method stands out for its practical applicability,requiring no model training and exhibiting low computational complexity,making it a viable solution for real-world scenarios. 展开更多
关键词 Video steganography video steganalysis motion vector prediction motion vector difference advanced motion vector prediction local optimality
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Some Convergence Properties for Weighted Sums of Martingale Difference Random Vectors
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作者 Yi WU Xue Jun WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第4期1127-1142,共16页
Let{X_(ni),F_(ni);1≤i≤n,n≥1}be an array of R^(d)martingale difference random vectors and{A_(ni),1≤i≤n,n≥1}be an array of m×d matrices of real numbers.In this paper,the Marcinkiewicz-Zygmund type weak law of... Let{X_(ni),F_(ni);1≤i≤n,n≥1}be an array of R^(d)martingale difference random vectors and{A_(ni),1≤i≤n,n≥1}be an array of m×d matrices of real numbers.In this paper,the Marcinkiewicz-Zygmund type weak law of large numbers for maximal weighted sums of martingale difference random vectors is obtained with not necessarily finite p-th(1<p<2)moments.Moreover,the complete convergence and strong law of large numbers are established under some mild conditions.An application to multivariate simple linear regression model is also provided. 展开更多
关键词 Martingale difference random vectors weighted sums Marcinkiewicz–Zygmund type weak law of large numbers complete convergence strong law of large numbers multivariate simple linear regression model
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Integrated Joint Source-Channel Decoding for H.264 Video Transmission
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作者 WU Jing CHEN Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1057-1062,共6页
This paper proposes an integrated joint source-channel decoder (I-JSCD) using Max-Log-MAP method for sources encoded with exp-Golomb codes and convolutional codes, and proposes a system applying this method to decod... This paper proposes an integrated joint source-channel decoder (I-JSCD) using Max-Log-MAP method for sources encoded with exp-Golomb codes and convolutional codes, and proposes a system applying this method to decoding the VLC data, e.g. motion vector differences (MVDs), of H.264 across an AWGN channel. This method combines the source code state-space and the channel code state-space together to construct a joint state-space, develops a 3-D trellis and a maximum a-posterior (MAP) algorithm to estimate the source sequence symbol by symbol, and then uses max-log approximation to simplify the algorithm. Experiments indicate that the proposed system gives significant improvements on peak signal-to-noise ratio (PSNR) (maximum about 15 dB) than a separate scheme. This also leads to a higher visual quality of video stream over a highly noisy channel. 展开更多
关键词 H.264 motion vector difference (MVD) integrated joint source-channel decoding (I-JSCD) variable-length code (VLC) exp-Golomb code MAX-LOG-MAP
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A New Method of Color Edge Detection Based on Local Structure Analysis
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作者 江舒 周越 朱巍巍 《Journal of Donghua University(English Edition)》 EI CAS 2008年第6期718-725,共8页
Human's real life is within a colorful world. Compared to the gray images, color images contain more information and have better visual effects. In today's digital image processing, image segmentation is an im... Human's real life is within a colorful world. Compared to the gray images, color images contain more information and have better visual effects. In today's digital image processing, image segmentation is an important section for computers to "understand" images and edge detection is always one of the most important methods in the field of image segmentation. Edges in color images are considered as local discontinuities both in color and spatial domains. Despite the intensive study based on integration of single-channel edge detection results, and on vector space analysis, edge detection in color images remains as a challenging issue. 展开更多
关键词 color edge detection local structure analysis local homogeneity color difference vector
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A Method on Analog Circuit Fault Diagnosis with Tolerance
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作者 Yan-Jun Li Hou-Jun Wang Ruey-Wen Liu 《Journal of Electronic Science and Technology of China》 2009年第4期297-302,共6页
In this paper, it is proved that the direction of the node-voltage difference vector, which is the difference between the node-voltage vector at faulty state and the one at the nominal state, is determined only by the... In this paper, it is proved that the direction of the node-voltage difference vector, which is the difference between the node-voltage vector at faulty state and the one at the nominal state, is determined only by the location of the faulty clement in linear analog circuits. Considering that the direction of the node-voltage sensitivity vector is the same as the one of the node-voltage difference vector and also considering that the module of the node-voltage sensitivity vector presents the weight of the parameter of faulty element deviation relative to the voltage difference, fault dictionary is set up based on node-voltage sensitivity vectors. A decision algorithm is proposed concerned with both the location and the parameter difference of the faulty element. Single fault and multi-fault can be diagnosed while the circuit parameters deviate within the tolerance range of 10 %. 展开更多
关键词 Analog circuit fault diagnosis fault dictionary node-voltage difference vector sensitivity vector.
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