2012
2012
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Record 157 of
Title:Improved particle filter based on fine resampling algorithm
Author(s):Cao, Bei(1,2); Ma, Cai-Wen(1); Liu, Zhen-Tao(3)Source: Journal of China Universities of Posts and Telecommunications Volume: 19 Issue: 2 DOI: 10.1016/S1005-8885(11)60253-7 Published: April 2012Abstract:In order to solve particle degeneracy phenomenon and simultaneously avoid sample impoverishment, this paper proposed an improved particle filter based on fine resampling algorithm for general case, called as particle filter with fine resampling (PF-FR). By introducing distance-comparing process and generating new particle based on optimized combination scheme, PF-FR filter performs better than generic sampling importance resampling particle filter (PF-SIR) both in terms of effectiveness and diversity of the particle system, hence, evidently improving estimation accuracy of the state in the nonlinear/non-Gaussian models. Simulations indicate that the proposed PF-FR algorithm can maintain the diversity of particles and thus achieve the same estimation accuracy with less number of particles. Consequently, PF-FR filter is a competitive choice in the applications of nonlinear state estimation. ? 2012 The Journal of China Universities of Posts and Telecommunications.Accession Number: 20122115045351 -
Record 158 of
Title:Research on signal processing of a precise photoelectric angle measuring system
Author(s):Ma, Qiang(1); Wu, Yiming(1); Xiao, Maosen(1); Wang, Haixia(1)Source: 2012 IEEE 5th International Conference on Advanced Computational Intelligence, ICACI 2012 Volume: Issue: DOI: 10.1109/ICACI.2012.6463368 Published: 2012Abstract:This paper introduces a research on signal processing of a precision photoelectric angle measuring system, and some key issues of the problem are also discussed and analyzed in detail. The basic principle of this measuring method is introduced in this paper. In order to avoid low frequency noise (such as generation recombination noise and 1/f noise), we choose to modulate the light source so that we can analyze the useful information in a high frequency domain. By using the data acquisition system (based on DSP and FPGA) to gather multiplex data, we can realize data-transmitting with network in a high speed. Writing algorithm by Lab VIEW software in the data processing, we can eventually gain the angle. Prototype test shows that this method can completely meet the system requirements for the measuring system. ? 2012 IEEE.Accession Number: 20131116105484 -
Record 159 of
Title:Approximation analysis of empirical feature-based learning with truncated sparsity
Author(s):Chen, Hong(1); Xiang, Hu-Zhou(1); Tang, Yi(2); Yu, Zhao(1); Zhang, Xiao-Li(1)Source: International Conference on Wavelet Analysis and Pattern Recognition Volume: Issue: DOI: 10.1109/ICWAPR.2012.6294765 Published: 2012Abstract:A sparse algorithm, based on empirical feature selection, is investigated from the viewpoint of learning theory. It is a novel way to realize sparse empirical feature-based learning different from the regularized kernel projection machines. Representer theorem and error analysis of this algorithm are established without sparsity assumption of regression function. An empirical study verifies our theoretical analysis. ? 2012 IEEE.Accession Number: 20124415609326 -
Record 160 of
Title:Color fusion method for low-light-level and infrared images in night vision
Author(s):Yang, Shaokui(1,2); Liu, Wen(1); Deng, Chan(1,2); Zhang, Xin(1)Source: 2012 5th International Congress on Image and Signal Processing, CISP 2012 Volume: Issue: DOI: 10.1109/CISP.2012.6469757 Published: 2012Abstract:The fusion of low-light-level image and infrared image can increase the reliability of interpretation since it combines the complementary information in multispectral images, and that a color fused image can improve human observer performance and reaction times. To obtain a color night vision image by dual band sensors (visible and infrared), we first adopt the false color fusion scheme by principles of biological opponent-color vision, then transfer the first order statistics of a natural color image (target image) to the false color fused image in a perceptually decorrelated YCbCr color space. In order to give prominence to targets and details in the result, we produce a grayscale fused image using principal component analysis of the visible and infrared images, and substitute it for the Y component during the color transfer procedure. Finally, we illustrated an example of the whole fusing process. The realistic, colorful and natural fused image demonstrates validity of the method. ? 2012 IEEE.Accession Number: 20131216133818 -
Record 161 of
Title:Multi-scale dictionary for single image super-resolution
Author(s):Zhang, Kaibing(1); Gao, Xinbo(1); Tao, Dacheng(2); Li, Xuelong(3)Source: Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition Volume: Issue: DOI: 10.1109/CVPR.2012.6247791 Published: 2012Abstract:Reconstruction- and example-based super-resolution (SR) methods are promising for restoring a high-resolution (HR) image from low-resolution (LR) image(s). Under large magnification, reconstruction-based methods usually fail to hallucinate visual details while example-based methods sometimes introduce unexpected details. Given a generic LR image, to reconstruct a photo-realistic SR image and to suppress artifacts in the reconstructed SR image, we introduce a multi-scale dictionary to a novel SR method that simultaneously integrates local and non-local priors. The local prior suppresses artifacts by using steering kernel regression to predict the target pixel from a small local area. The non-local prior enriches visual details by taking a weighted average of a large neighborhood as an estimate of the target pixel. Essentially, these two priors are complementary to each other. Experimental results demonstrate that the proposed method can produce high quality SR recovery both quantitatively and perceptually. ? 2012 IEEE.Accession Number: 20124015484215 -
Record 162 of
Title:Design of long-wave infrared scan system with large field and large aperture
Author(s):Fan, Zheyuan(1,2); Yang, Hongtao(1,2); Qu, Enshi(1); Zhang, Jian(1); Cao, Jianzhong(1); Zhang, Zhi(1); Chen, Weining(1); Wu, Li(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 10 DOI: Published: October 2012Abstract:Using 288 ×4 detector with secondary imaging, a long-wave scan optical system with large field and large aperture working at 7.5-10.5 μm was designed. The system had advantages of large aperture, high image quality etc. The number of F was 1.67, FOV was 28° × 21°, which extended to 78° × 57° after adopting scan mirror and dual-wedge prism. Because there were a limited number of lens materials used in MWIR spectral bands, to balance chromatic aberration, the ZnSe material and Germanium material were adopted, aspheres were adopted to balance sphere aberrations. The results show that the optical performance approximates to the diffraction limit and the design has better achromatic performance. The modulation transfer function (MTF) is above 0.3 at spatial frequency of 20 lp/mm and energy concentration ratio is greater than 70% within the sensing element of the detector.Accession Number: 20125015795980 -
Record 163 of
Title:Stray light analysis for hyper-spectral imaging spectrometer
Author(s):Wang, Meiqin(1,2); Wang, Zhonghou(1); Bai, Jiaguang(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 6 DOI: Published: June 2012Abstract:Stray light analysis is one of the crucial technologies to ensure the imaging quality of hyper- spectral imager system. The detailed stray light analysis for hyper-spectral imager system was described. Firstly, the primary baffle, secondary baffle and outer baffle were designed. Secondary, the solid model of the hyper-spectral imager system was constructed in Tracepro software and the first and second order scattering surface were determined, then important sampling was installed on the major scattering path. At last, the Point Sources Transmittance was calculated at different off-axis angle between 0.5°-40°. According to the Point Source Transmittance, the illumination of surface reflected light is 5.5 × 10-3 W/m2 out of critical angle of stray light between 0.5°-40°, which is 3.5% less than the illumination of central field of view. The analysis result shows that the stray light can meet the requirement.Accession Number: 20123715424640 -
Record 164 of
Title:A method of identifying and locating encoded artificial points automatically in close range digital photogrammetry
Author(s):Wang, Yongwang(1); Wu, Yiming(1); Zhao, Xiaojin(1); Yao, Zhen(1); Li, Chunyan(1)Source: 2012 IEEE 5th International Conference on Advanced Computational Intelligence, ICACI 2012 Volume: Issue: DOI: 10.1109/ICACI.2012.6463246 Published: 2012Abstract:Using coding artificial point can match the homonymy points during multiple images automatically in the photogrammetry. A method of identifying and locating 8 bits encoded points automatically has been presented in this paper. The experimental results show that the accuracy of center coordinate of encoding point reaches sub-pixel level. And decoding method is simple. The robust of decoding and recognition rate is high. So it can meet the requirements of close range photogrammetry fully. ? 2012 IEEE.Accession Number: 20131116105363 -
Record 165 of
Title:Pose estimation algorithm with line matching by utilizing quaternion
Author(s):Li, Zhe(1,2); Su, Xiuqin(1,2); Hao, Wei(1,2)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 8 DOI: Published: August 2012Abstract:Pose estimation based on the parameters of camera has been studied extensively and it has been applied to many areas such as computer vision and robotics. Calculation using 3D geometric features and its corresponding 2D geometric features is a significant method to estimate camera poses. Given to this fact, a novel algorithm was proposed based on 3D to its corresponding 2D geometric features, aiming at estimating monocular camera poses. In this algorithm, rotation matrix was denoted by quaternion, and rotation parameters and translation parameters were obtained by constraint equation. Compared with the NLL algorithm proposed by Ansar, this algorithm was more effective in reducing the influence of image noise on pose estimation accuracy. Meanwhile, it can ensure the orthogonality of rotation matrix. The result of simulation experiment shows that compared with NLL algorithm, the new algorithm obviously presents stronger robustness, higher calculation accuracy and computational complexity. The validity of this algorithm is verified by an actual experiment.Accession Number: 20124415622975 -
Record 166 of
Title:Design and implementation of real-time processing platform for movement error correction of hyperspectrual imaging
Author(s):Yu, Tao(1,2); Hu, Bing-Liang(1); Gao, Xiao-Hui(1,2); Wei, Ru-Yi(1,2); Jing, Juan-Juan(1,2)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 32 Issue: 8 DOI: 10.3964/j.issn.1000-0593(2012)08-2275-05 Published: August 2012Abstract:The approach that deals with compressed and packed image data transmitted from satellite to the ground is too slow for real-time application occasion, it also has huge image, multi-processing step and complexity recovery arithmetic synchronously, so it is urgent to build accurate and fast data processing platform for real-time processing. For the moment, the platform for data recovery and error correction is much less, the so-called successful platform may directly affect the effect of target detection and identification because of processing speed, precision, flexibility, configuration and upgrade. The platform we build is to set spatial modulation spectrometer as the research goal, We design and implement a hardware platform based on Xilinx Virtex-5 FPGA, It is combined with ISE IP soft-core resources which is configurable, high-precision and flexible by focusing on analyzing key aspects of the hardware platform. And the relevant test data were drawn, then a good way for spectrum recovery and error correction was explored.Accession Number: 20123715424462 -
Record 167 of
Title:Method for improving wavefront detection accuracy based on high moment
Author(s):Xia, Aili(1,2); Ma, Caiwen(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 2 DOI: Published: February 2012Abstract:The accuracy of the Shack-Hartmann wavefront sensor for measuring the distortion wavefront is mainly dependent upon the measurement accuracy of the centroid of focal spot. An improved centroid measurement approach was presented which calculated the centroid of focal spot more precisely using the higher moment centroid method in an optimized detection window. Firstly, the approximate center of the focal spot by the first moment centroid algorithm in the whole sub-aperture was obtained. Secondly, a rectangular window including the whole focal spot was established, whose center was just the obtained approximate center. Finally, the centroid of focal spot by the higher moment centroid algorithm in the optimized window was calculated again. Based on the improved method, the effects of various noises out of the optimized detection window were almost eliminated. Furthermore, the noise influences in the optimized detection window were also weakened due to the more contributions of the focal spot intensity. The experimental results demonstrate that the precision, repeatability and stability of the centroid measurement of focal spot are more prominent than the results obtained via other commonly centroid methods.Accession Number: 20121514940938 -
Record 168 of
Title:Multiple slope integration based on CMOS image sensor
Author(s):Yang, Donglai(1,2); Hu, Xiaodong(1); Li, Junna(3)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 6 DOI: Published: June 2012Abstract:Compared with CCD (Charge Coupled Device), the dynamic range of CMOS image sensor is narrower, which is due to its self-characteristics. With high-performance CMOS image sensor IBIS5-A-1 300 produced by CYPRESS company as the object, a research was made on the theory of its multiple slope integration, and the integration mode was used to extend its dynamic range. The design method of multiple slope integration's timing was advanced with FPGA and DSP as the hardware system. With Quartus II 7.0, the designed driver timing was simulated in function. The new designed multiple slope integration timing drive extended the optical dynamic range of CMOS image sensor, from original model of single slope integration mode 64 dB to 90 dB. The experiment result shows that multiple slope integration mode can achieve the purpose of extending the dynamic range.Accession Number: 20123715424634