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Robust Image Restoration for Motion Blur of Image Sensors 期刊论文  OAI收割
SENSORS, 2016, 卷号: 16, 期号: 6
作者:  
Yang, Fasheng;  Huang, Yongmei;  Luo, Yihan;  Li, Lixing;  Li, Hongwei
收藏  |  浏览/下载:33/0  |  提交时间:2016/10/27
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).  
Improvement of urban land use and land cover classification approach in arid areas 会议论文  OAI收割
Proceedings of SPIE - The International Society for Optical Engineering, Image and Signal Processing for Remote Sensing XVI, Toulouse, France, 2010
Qian; Jing1; 2; Zhou; Qiming1; Chen; Xi2
收藏  |  浏览/下载:35/0  |  提交时间:2011/08/23
A high-speed image sensing technique with adjustable frame rate based on an ordinary CCD 期刊论文  OAI收割
optik, 2008, 卷号: 119, 期号: 11, 页码: 548, 552
He Guotian; 王向朝; Li Dailin; Hu Jianmin
收藏  |  浏览/下载:1088/176  |  提交时间:2009/09/18
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:26/0  |  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.  
Design and DSP implementation of star image acquisition and Star point fast acquiring tracking (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:  
Wang X.;  Wang X.;  Wang X.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Star sensor is a special high accuracy photoelectric sensor. Attitude acquisition time is an important function index of star sensor. In this paper  the design target is to acquire 10 samples per second dynamic performance. On the basis of analyzing CCD signals timing and star image processing  a new design and a special parallel architecture for improving star image processing are presented in this paper. In the design  the operation moving the data in expanded windows including the star to the on-chip memory of DSP is arranged in the invalid period of CCD frame signal. During the CCD saving the star image to memory  DSP processes the data in the on-chip memory. This parallelism greatly improves the efficiency of processing. The scheme proposed here results in enormous savings of memory normally required. In the scheme  DSP HOLD mode and CPLD technology are used to make a shared memory between CCD and DSP. The efficiency of processing is discussed in numerical tests. Only in 3.5ms is acquired the five lightest stars in the star acquisition stage. In 43us  the data in five expanded windows including stars are moved into the internal memory of DSP  and in 1.6ms  five star coordinates are achieved in the star tracking stage.  
An image identification system of seal with fingerprint based on CMOS image sensor (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Xue X.-C.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
CMOS image sensors now become increasingly competitive with respect to their CCD counterparts  while adding advantages such as no blooming  simpler driving requirements and the potential of on-chip integration of sensor  analog signal conditioning circuits  A/D converter and digital processing functions. Furthermore  CMOS sensors are the best choices for low-cost imaging systems. An image identification system based on CMOS image sensor is used to identify the seal images that include fingerprint  and then determine whether the seal is fake or not. The system consists of a color CMOS image sensor (OV2610)  a buffer memory  a CPLD  a MCU (P89C61X2)  a USB2.0 interface chip (ISP1581) and a personal computer. The CPLD implement the logic and timing of the system. The MCU and the USB2.0 interface chip deal with the communications between the images acquisition system and PC. Thus PC can send some parameters and commands to the images acquisition system and also read image data from it. The identification of the images of seal is processed by the PC. The structure and scheme of the system are discussed in detail in this paper. Several test images of seal taken by the system are also provided in the paper.