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	Research on infrared dim-point target detection and tracking under sea-sky-line complex background (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: Dong Y.-X.; Zhang H.-B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：111/0 \| 提交时间：2013/03/25 Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms such as adaptive background prediction detecting method. When background has dispersion-decreasing structure the traditional target detection algorithms would be more useful. But when the background has large gray gradient such as sea-sky-line sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature in our opinion from the perspective of mathematics the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore the purpose of the image preprocessing is to reduce the effects from noise also to raise the SNR of image and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics the median filter is used to eliminate noise improve signal-to-noise ratio then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (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.
	Adaptive deformation estimation of moving target by weight image analysis (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Future Computer and Communication, ICFCC 2010, May 21, 2010 - May 24, 2010, Wuhan, China Bai X.-G.; Dai M. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 An algorithm based on weight image analysis is proposed for adaptive deformation estimation of moving target in mean-shift tracking method. At the first we get the weight image from the target candidate region. Then we analyze the differences between the object and background. According to that the area estimation of the target can be converted into the image segmentation task. To realize the adaptive segmentation and estimation we define the threshold as the maximum variance between object and background. Combining the estimated area and covariance matrix we can estimate the width height and orientation of the object. The experimental results on three representative video sequences validate its robustness to the deformable estimation of the targets. 2010 IEEE.
	The research for missile bullets' multiple targets of opto-electronic theodolites (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 Wei Z.; Liu Y.-H. 收藏 \| 浏览/下载：44/0 \| 提交时间：2013/03/25 The system of opto-electronic theodolites for measuring missile bullet provides parameter of missile bullet trajectory and affords primacy scientific data for completing campaign assign and obtaining ideal result of destroy. This article researches extraction arithmetic for missile bullet' multiple targets. Above all enactment threshold of area acquire middle axes of target by adopting Hough transforming and approximating and calculate obliquity angles of targets. In course of matching accomplish missile bullet's multiple targets data association of serial images by making use of improving eigenfunction and achieve extraction of missile bullet's multiple targets after obtaining center position of targets adopting OSTU method change numeral image into binary image according to area of target forecast searching region of target matching by using Kalman filter area of targets and abstract separately center position of targets and area of targets judge conglutination and obstruct then separate targets in term of wave crest and trough's variety of grey histogram of conglutination region grey average of target and obliquity angles of targets. The experimental result shows that right ratio of the extraction targets reach to 90%. The article use correct mathematical model and reasonable arithmetic and obtain effectively parameter of missile bullet' multiple targets. 2010 IEEE. at the same time obtain grey average of target mark target region
	Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Li J.; Liu J.; Liu J.; Liu J.; Li J. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.