2011
2011
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Record 217 of
Title:Lossless data embedding using generalized statistical quantity histogram
Author(s):Gao, Xinbo(1); An, Lingling(1); Yuan, Yuan(2); Tao, Dacheng(3); Li, Xuelong(2)Source: IEEE Transactions on Circuits and Systems for Video Technology Volume: 21 Issue: 8 DOI: 10.1109/TCSVT.2011.2130410 Published: August 2011Abstract:Histogram-based lossless data embedding (LDE) has been recognized as an effective and efficient way for copyright protection of multimedia. Recently, a LDE method using the statistical quantity histogram has achieved good performance, which utilizes the similarity of the arithmetic average of difference histogram (AADH) to reduce the diversity of images and ensure the stable performance of LDE. However, this method is strongly dependent on some assumptions, which limits its applications in practice. In addition, the capacities of the images with the flat AADH, e.g., texture images, are a little bit low. For this purpose, we develop a novel framework for LDE by incorporating the merits from the generalized statistical quantity histogram (GSQH) and the histogram-based embedding. Algorithmically, we design the GSQH driven LDE framework carefully so that it: 1) utilizes the similarity and sparsity of GSQH to construct an efficient embedding carrier, leading to a general and stable framework; 2) is widely adaptable for different kinds of images, due to the usage of the divide-and-conquer strategy; 3) is scalable for different capacity requirements and avoids the capacity problems caused by the flat histogram distribution; 4) is conditionally robust against JPEG compression under a suitable scale factor; and 5) is secure for copyright protection because of the safe storage and transmission of side information. Thorough experiments over three kinds of images demonstrate the effectiveness of the proposed framework. ? 2011 IEEE.Accession Number: 20113214224073 -
Record 218 of
Title:Mathematical model of the laser frequency shift modulated by small signal low frequency current
Author(s):Yan, Deke(1,2); Zhong, Zhen(3); Sun, Chuandong(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 40 Issue: 8 DOI: Published: August 2011Abstract:When laser transmits through the fiber, the more narrow of the laser spectral line width is, the more lower of the threshold for the stimulated Brillouin scattering is. High power laser tends to bring stimulated Brillouin scattering, thereby affecting the laser transmission. Modulating the high power laser diode by small signal current is one of the means for solving this problem. Effected by the sine small signal modulating current, the output laser of the distributed feedback semiconductor laser diode could produce frequency shift and broaden the spectral line width. Accordingly, it could increase the threshold of stimulated Brillouin scattering and reduce the transmission loss. It was shown that the mathematical expression for the laser frequency shift associated with modulating current's amplitude and frequency on the condition of sine small signal low frequency modulating current. Then, the relative electro-optical system was also designed for the experiment. And then, the parameters of the mathematical model were obtained by data fitting.Accession Number: 20114214432393 -
Record 219 of
Title:Semisupervised dimensionality reduction and classification through virtual label regression
Author(s):Nie, Feiping(1); Xu, Dong(1); Li, Xuelong(2); Xiang, Shiming(3)Source: IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics Volume: 41 Issue: 3 DOI: 10.1109/TSMCB.2010.2085433 Published: June 2011Abstract:Semisupervised dimensionality reduction has been attracting much attention as it not only utilizes both labeled and unlabeled data simultaneously, but also works well in the situation of out-of-sample. This paper proposes an effective approach of semisupervised dimensionality reduction through label propagation and label regression. Different from previous efforts, the new approach propagates the label information from labeled to unlabeled data with a well-designed mechanism of random walks, in which outliers are effectively detected and the obtained virtual labels of unlabeled data can be well encoded in a weighted regression model. These virtual labels are thereafter regressed with a linear model to calculate the projection matrix for dimensionality reduction. By this means, when the manifold or the clustering assumption of data is satisfied, the labels of labeled data can be correctly propagated to the unlabeled data; and thus, the proposed approach utilizes the labeled and the unlabeled data more effectively than previous work. Experimental results are carried out upon several databases, and the advantage of the new approach is well demonstrated. ? 2010 IEEE.Accession Number: 20112214010913 -
Record 220 of
Title:Vehicle detection and motion analysis in low-altitude airborne video under urban environment
Author(s):Cao, Xianbin(1); Wu, Changxia(2); Lan, Jinhe(2); Yan, Pingkun(3); Li, Xuelong(3)Source: IEEE Transactions on Circuits and Systems for Video Technology Volume: 21 Issue: 10 DOI: 10.1109/TCSVT.2011.2162274 Published: October 2011Abstract:Visual surveillance from low-altitude airborne platforms plays a key role in urban traffic surveillance. Moving vehicle detection and motion analysis are very important for such a system. However, illumination variance, scene complexity, and platform motion make the tasks very challenging. In addition, the used algorithms have to be computationally efficient in order to be used on a real-time platform. To deal with these problems, a new framework for vehicle detection and motion analysis from low-altitude airborne videos is proposed. Our paper has two major contributions. First, to speed up feature extraction and to retain additional global features in different scales for higher classification accuracy, a boosting light and pyramid sampling histogram of oriented gradients feature extraction method is proposed. Second, to efficiently correlate vehicles across different frames for vehicle motion trajectories computation, a spatio-temporal appearance-related similarity measure is proposed. Compared to other representative existing methods, our experimental results showed that the proposed method is able to achieve better performance with higher detection rate, lower false positive rate, and faster detection speed. ? 2011 IEEE.Accession Number: 20114114414394 -
Record 221 of
Title:Non-goal scene analysis for soccer video
Author(s):Gao, Xinbo(1); Niu, Zhenxing(1); Tao, Dacheng(2); Li, Xuelong(3)Source: Neurocomputing Volume: 74 Issue: 4 DOI: 10.1016/j.neucom.2010.09.013 Published: January 2011Abstract:The broadcast soccer video is usually recorded by one main camera, which is constantly gazing somewhere of playfield where a highlight event is happening. So the camera parameters and their variety have close relationship with semantic information of soccer video, and much interest has been caught in camera calibration for soccer video. The previous calibration methods either deal with goal scene, or have strict calibration conditions and high complexity. So, it does not properly handle the non-goal scene such as midfield or center-forward scene. In this paper, based on a new soccer field model, a field symbol extraction algorithm is proposed to extract the calibration information. Then a two-stage calibration approach is developed which can calibrate camera not only for goal scene but also for non-goal scene. The preliminary experimental results demonstrate its robustness and accuracy. ? 2010 Elsevier B.V.Accession Number: 20105113505146 -
Record 222 of
Title:Learning similarity with multikernel method
Author(s):Tang, Yi(1); Li, Luoqing(1); Li, Xuelong(2)Source: IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics Volume: 41 Issue: 1 DOI: 10.1109/TSMCB.2010.2048312 Published: February 2011Abstract:In the field of machine learning, it is a key issue to learn and represent similarity. This paper focuses on the problem of learning similarity with a multikernel method. Motivated by geometric intuition and computability, similarity between patterns is proposed to be measured by their included angle in a kernel-induced Hilbert space. Having noticed that the cosine of such an included angle can be represented by a normalized kernel, it can be said that the task of learning similarity is equivalent to learning an appropriate normalized kernel. In addition, an error bound is also established for learning similarity with the multikernel method. Based on this bound, a boosting-style algorithm is developed. The preliminary experiments validate the effectiveness of the algorithm for learning similarity. ? 2010 IEEE.Accession Number: 20110613652036 -
Record 223 of
Title:A precision carbon fiber hexapod for the installation of an optical telescope
Author(s):Li, Chuang(1); Ren, Guorui(1); Wang, Wei(1); He, Tianbing(1); Lin, Liming(1); Yang, Wengang(1); Fan, Xuewu(1)Source: 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011 - Proceedings Volume: Issue: DOI: 10.1109/MACE.2011.5987095 Published: 2011Abstract:A carbon fiber hexapod was used to install an optical telescope on the payload instrument module of a satellite. In order to reduce distortion stresses, titanium alloy brackets with flexure sections were employed to connect the end fittings of the carbon fiber struts. The design, fabrication and assembling of the carbon fiber hexapod were discussed. The developed hexapod passed the qualified level vibration test. The test results show that the hexapod could reduce vibration response in high frequency. ? 2011 IEEE.Accession Number: 20114314453166 -
Record 224 of
Title:Segmenting images by combining selected atlases on manifold
Author(s):Cao, Yihui(1); Yuan, Yuan(1); Li, Xuelong(1); Turkbey, Baris(2); Choyke, Peter L.(2); Yan, Pingkun(1)Source: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) Volume: 6893 LNCS Issue: PART 3 DOI: 10.1007/978-3-642-23626-6_34 Published: 2011Abstract:Atlas selection and combination are two critical factors affecting the performance of atlas-based segmentation methods. In the existing works, those tasks are completed in the original image space. However, the intrinsic similarity between the images may not be accurately reflected by the Euclidean distance in this high-dimensional space. Thus, the selected atlases may be away from the input image and the generated template by combining those atlases for segmentation can be misleading. In this paper, we propose to select and combine atlases by projecting the images onto a low-dimensional manifold. With this approach, atlases can be selected according to their intrinsic similarity to the patient image. A novel method is also proposed to compute the weights for more efficiently combining the selected atlases to achieve better segmentation performance. The experimental results demonstrated that our proposed method is robust and accurate, especially when the number of training samples becomes large. ? 2011 Springer-Verlag.Accession Number: 20114114410429 -
Record 225 of
Title:Application of SIFT feature extraction algorithm on the image registration
Author(s):Liu, Jinxia(1); Qiu, Yuehong(1)Source: Proceedings - IEEE 2011 10th International Conference on Electronic Measurement and Instruments, ICEMI 2011 Volume: 3 Issue: DOI: 10.1109/ICEMI.2011.6037882 Published: 2011Abstract:Presents a high-accuracy image registration technique using SIFT and BBF. Conventional techniques of SIFT-based image registration are not very effective when searching for homonymy point-pairs, and eliminating mismatching. This paper proposes a technique to improve registration performance by BBF and RANSAC algorithm, BBF algorithm searches optimal homonymy point-pairs, and RANSAC algorithm eliminates mismatching. Experiments with real-world scenes demonstrate that the proposed method can reach a better precision and robustness, which outperforms previously proposed schemes, and makes possible to estimate image displacement with 0.01 pixel accuracy. ? 2011 IEEE.Accession Number: 20114414464782 -
Record 226 of
Title:Auto-compensation of velocity-height ratio for Chang'E-2 satellite CCD stereo camera
Author(s):Xue, Bin(1,2,3,4); Zhao, Baochang(1,3,4); Yang, Jianfeng(1,2,3,4); Gao, Wei(1,3,4); Qiao, Weidong(1,2,4); Ma, Xiaolong(1,2,4); Zhang, Bo(3,4); Liu, Jiahang(1,4); Zhao, Wei(1,3,4); Jing, Juanjuan(1,2,4)Source: Science China Technological Sciences Volume: 54 Issue: 9 DOI: 10.1007/s11431-011-4517-7 Published: September 2011Abstract:The TDI-CCD imaging method using auto-compensation of velocity-height ratio (VHR) was applied to Chang'E-2 satellite CCD stereo camera. Factors that influence the image quality of the camera were discussed, among which the mismatch error in VHR was found to be the main cause. An auto-compensation scheme for VHR was developed. The validity and effectiveness were proved by the on-orbit high quality images. ? 2011 Science China Press and Springer-Verlag Berlin Heidelberg.Accession Number: 20113314245071 -
Record 227 of
Title:Research on UV detector technology and application in MAWS
Author(s):Yao, Da-Wei(1); Hao, Wei(1); Yang, Xiao-Jun(1); Tian, Yan(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8194 Issue: DOI: 10.1117/12.901021 Published: 2011Abstract:The atmospheric transmission characteristics of ultraviolet radiation are unique, which have made ultraviolet detecting technology has been developed rapidly in military application domain. Missile approaching warning system based UV detecting technology distinguish target by detecting the ultraviolet radiation in solar blind spectrum from missile's plumes. This warning system is a passive warning system, which has advantages of good concealment, low false-alarm rate, cooling without low temperature, small size and light weight. It has been an important part of modern battlefield in the electro-optical countermeasure domain This paper expatiate the principle of ultraviolet detecting technology and introduce the developments about ultraviolet warning and related technology, including the ultraviolet transmission in the atmosphere, the ultraviolet radiance characteristic of target and background, the ultraviolet photoelectric detectors, and the ultraviolet detection technology. A suit of ultraviolet photoelectric imaging system has been designed. This system is made up of three parts, there are narrowband ultraviolet optical system in large field, ultraviolet ICCD camera and ultraviolet warming image processing device. A great deal of imaging experiments about ultraviolet target in several kinds of typical meteorological condition have been done, these images shows the system is efficient and reasonable. The characteristics of ultraviolet objective imaging be tested and evaluated by analyze the experiment images obtained by the system. This system provide theoretical and test bases for engineering research on ultraviolet missile approaching warning system. ? 2011 SPIE.Accession Number: 20113714325938 -
Record 228 of
Title:Strain measurement aided assembly for a CFRP hexapod
Author(s):Ren, Guorui(1); Li, Chuang(1); Wang, Wei(1); Fan, Xuewu(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8321 Issue: DOI: 10.1117/12.905366 Published: 2011Abstract:In order to mount a space optical telescope with long focal length on a spacecraft for an astronomy observation mission, a carbon fiber reinforced plastic (CFRP) hexapod with titanium alloy brackets was designed and fabricated. Each bracket has a pair of heads and each head has two orthogonal flexures as virtual pivots without clearance to provide flexure mounts. Because of no adjustment parts, slight differences among components and roughly assembly would result in misalignment and asymmetrical stress in the hexapod. The stresses and strains of the CFRP hexapod structure under 1G gravity load were analyzed with finite element method. In order to monitor the assembly stress and provide regulating guidance, strain gauges were stuck centrally on the bottom flexures of each bracket. Comparing the measured strains with the computed values, the low stress assembly of the CFRP hexapod has been accomplished successfully. ? 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).Accession Number: 20120114664558