中国科学院机构知识库网格系统: 检索

High-Precision Light Spot Position Detection in Low SNR Condition Based on Quadrant Detector 期刊论文 OAI收割
APPLIED SCIENCES-BASEL, 2019, 卷号: 9, 期号: 7
作者: Yu, Jiawei; Li, Qing; Li, Hongwei; Wang, Qiang; Zhou, Guozhong

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收藏 | 浏览/下载：26/0 | 提交时间：2021/05/06

free space optical communication quadrant detector light spot detection Kalman filter real-time calculation

The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Sun H.; Han H.-X.; Sun H.

收藏 | 浏览/下载：63/0 | 提交时间：2013/03/25

Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring precision and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure but in order to capture the change of the state space it need a certain amount of particles to ensure samples is enough and this number will increase in accompany with dimension and increase exponentially this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining" we expand the classic Mean Shift tracking framework.Based on the previous perspective we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information this approach also inhibit interference from the background ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Wang M.-J.; Wu Z.-G.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.

Design and analysis of Roll-Swing imaging seeker scan scheme (EI CONFERENCE) 会议论文 OAI收割
2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China
Bai Y.; Liu B.; Jia H.; Guo L.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

To achieve an optimum scan area and target stay time for Roll-Swing imaging seeker the scanning process is analyzed. The method of ground imaging area calculation is proposed in this paper. A kind of Roll-Swing imaging frame mechanism is introduced. The flight process simulation base on real flight data is realized. According to imaging sensor parameters and flight data a new scan scheme method is proposed and a new scan scheme is designed. The new scan scheme is compared to traditional scan scheme from different guide lines. The test results indicate that the new scan scheme satisfy requirement of the real flight experiment. 2010 IEEE.

Dynamic data fixing for IR target radiation characteristics (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Lihua C.; Juan C.

收藏 | 浏览/下载：33/0 | 提交时间：2013/03/25

The main methods to measure the target IR features are the following two ways: test and then measurement or theoretical and simulation calculation. The former is direct measurement so the results are more accurate but the test is costly and complicated so that it is limited in the application. Theoretical and simulation calculation are widely used in the target IR radiation calibration. Here we give the basic configuration of the calibration platform for measuring the IR radiation of the large area low temperature blackbody source and discuss the calibration flowchart and key technologies for atmospheric transmission correction. The dynamic data are analyzed in real time to determine the IR radiation features in the data fusion subsystem and the experimental results show that the calibration method is feasible and practical. 2010 IEEE.

Real-time matching algorithm of navigation image based on corner detection (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China
作者: Zhang T.

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In order to meet requirement of real-time and high accuracy in image matching aided navigation SSDA algorithm is used to match remote sensing image and template image coarsely a fast and effective algorithm of remote sensing image matching based on corner detection is put forward. With the combination of rough and fine match when the matching result is bigger than one to count absolute value sum of energy difference of characteristic point energy to realize fine match of remote sensing image and template image to locate the position of template image in remote sensing image accurately. Simulation experiment proves that the matching of a remote sensing image resolution of 1018*1530 and a template image resolution of 150*90 can be fulfilled within 2.392 second wavelet transform is used to acquire low frequency component to realize image compression to decrease calculation work and increase matching speed. Harris corner detection algorithm is used to detect corner of remote sensing image and template image and energy of every corner is calculated the algorithm is robust and effective real time image navigation can be achieved. 2009 SPIE.

Modeling and analysis of dialyte-lens auto-focusing technology for theodolite (EI CONFERENCE) 会议论文 OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Wu L.-T.; Qiao Y.-F.; Wu D.-K.; Cai S.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

In order to realize real-time auto-focusing for theodolite lens-apart method was designed with the corresponding math model built and analyzed. An Object beam splitted after the first image surface of the theodolite traveled through two dialyte lens and then was imaged on CCD. The distance between two spots when exactly focused was set as the calibration value and the relationship between defocus distance and spot offset was given. The influence of tracking center shift and divergence angle etc. on focusing accuracy was analyzed. Compared with the traditional focusing method this scheme has a higher accuracy faster calculation higher tolerance for environment temperature and a simpler construction. The experiment result exhibited a resolution higher than 0.056mm which shows a bright engineering application prospect for this method. 2009 SPIE.

Application of multi-sensors parallel fusion system in photoelectric tracing (EI CONFERENCE) 会议论文 OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Cheng G.-Y.; Cai S.; Gao H.-B.; Zhang S.-M.; Qiao Y.-F.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

To solve the real-time and reliability problem of tracking servo-control system in optoelectronic theodolite a multisensors parallel processing system was proposed. Misdistances of three different wavebands were imported into system and then prediction was done in DSP1 to get the actual position information. Data fusion was accomplished in PPGA imported by multi channel buffer serial port. The compound position information was used to control the theodolite. The results were compared with external guide data in DSP2 to implement correction of above calculation and then were imported to epistemic machine through PXI interface. The simulation experiment of each calculation unit showed that this system could solve the real-time problem of feature level data fusion. The simulation result showed that the system can satisfy the real-time requirement with 1.25ms in theodolite with three imaging systems while sampling frequency of photoelectric encoder was 800 Hz. 2009 SPIE.

Real time tracking by LOPF algorithm with mixture model (EI CONFERENCE) 会议论文 OAI收割
MIPPR 2007: Automatic Target Recognition and Image Analysis; and Multispectral Image Acquisition, November 15, 2007 - November 17, 2007, Wuhan, China
Meng B.; Zhu M.; Han G.; Wu Z.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

A new particle filter-the Local Optimum Particle Filter (LOPF) algorithm is presented for tracking object accurately and steadily in visual sequences in real time which is a challenge task in computer vision field. In order to using the particles efficiently we first use Sobel algorithm to extract the profile of the object. Then we employ a new Local Optimum algorithm to auto-initialize some certain number of particles from these edge points as centre of the particles. The main advantage we do this in stead of selecting particles randomly in conventional particle filter is that we can pay more attentions on these more important optimum candidates and reduce the unnecessary calculation on those negligible ones in addition we can overcome the conventional degeneracy phenomenon in a way and decrease the computational costs. Otherwise the threshold is a key factor that affecting the results very much. So here we adapt an adaptive threshold choosing method to get the optimal Sobel result. The dissimilarities between the target model and the target candidates are expressed by a metric derived from the Bhattacharyya coefficient. Here we use both the counter cue to select the particles and the color cur to describe the targets as the mixture target model. The effectiveness of our scheme is demonstrated by real visual tracking experiments. Results from simulations and experiments with real video data show the improved performance of the proposed algorithm when compared with that of the standard particle filter. The superior performance is evident when the target encountering the occlusion in real video where the standard particle filter usually fails.

Displacement estimation by the phase-shiftings of fourier transform in present white noise (EI CONFERENCE) 会议论文 OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者: Wu Y.-H.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

Displacement estimation is a fundamental problem in Real-time video image processing. It can be typically approached by theories based on features in spatial domain. This paper presents an algorithm which improves the theory for estimating the moving object's displacement in spatial domain by its Fourier transform frequency spectrum. Because of the characters of Fourier transform the result is based on all the features in the image. Utilizing shift theorem of Fourier transform and auto-registration the algorithm employs the phase spectrum difference in polar coordinate of two frame images sequence with the moving target1 2. The method needn't transform frequency spectrum to spatial domain after calculation comparing with the traditional algorithm which has to search Direc peak and it reduces processing time. Since the technique proposed uses all the image information including all the white noise in the image especially and it's hard to overcome the aliasing from noises but the technique can be an effective way to analyze the result in little white noise by the different characters between high and low frequency bands. It can give the displacement of moving target within 1 pixel of accuracy. Experimental evidence of this performance is presented and the mathematical reasons behind these characteristics are explained in depth. It is proved that the algorithm is fast and simple and can be used in image tracking and video image processing.