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	A novel remote sensing image retrieval method based on visual salient point features 期刊论文 OAI收割 SENSOR REVIEW, 2014, 卷号: 34, 期号: 4, 页码: 349-359 作者: Wang, Xing; Shao, Zhenfeng; Zhou, Xiran; Liu, Jun \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2018/03/15 Image retrieval Image key points Remote sensing images Visual attention models
	Image registration based on Mexican-hat wavelets and pseudo-Zernike moments (EI CONFERENCE) 会议论文 OAI收割 2012 World Automation Congress, WAC 2012, June 24, 2012 - June 28, 2012, Puerto Vallarta, Mexico 作者: Liu Y.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 Image registration is a key technique in pattern recognition and image processing and it is widely used in many application areas such as computer vision remote sensing image fusion and object tracking. A method for image registration combining Mexican-hat wavelets and pseudo-Zernike moments is proposed. Firstly feature points are extracted using scale-interaction Mexican-hat wavelets in the reference image and sensed image respectively. Then pseudo-Zernike moments are used to match them and classical RANSAC used to eliminate the wrong matches. And then the well match points are used to estimate the best affine transform parameters by least squares minimization. At last the sensed image is transformed and resampled to accomplish the image registration. The experiments indicate that the proposed algorithm extracts feature points and matches them exactly and eliminates wrong matched points effectively and achieves nice registration results. 2012 TSI Press.
	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).
	Research on the laboratory radiometric calibration of the thermal imager (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Wang J.; Liu Y.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 The radiometric calibration of the thermal imager was investigated to build the relationship between the input radiance and the digital output to realize the temperature measurement. The radiometric calibration was implemented in the State Key Laboratory of Applied Optics. A standard black body source was served as radiation source. The response of the thermal imager to the input radiance was tested for different gains. The experimental results show that the average grey level of the output imaging is linear dependence of the input radiance. Because the radiance in the receiving wave range of the thermal imager is linear with the black body's temperature based on Planck's law of radiation the average grey level of the output image is also linear with the black body's temperature after fitting a curve to the experiment data points. Then the relationship of the response and the gain was studied when the black body's temperature kept constant. The preliminary analysis of calibration data shows that the response of the thermal imager is linear and the average grey value of the image is directly proportion to the gain. According to the experimental results the reference gains and the dynamic range of temperature measurement were obtained. Finally the uncertainty influencing the calibration results was analyzed the analysis shows the maximal uncertainty is 5.2% which can meet the calibration requirement less than 10%. 2010 Copyright SPIE - The International Society for Optical Engineering.
	A new algorithm of image segmentation for overlapping grain image (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Image segmentation is primary issue in image processing at the same time it is principal problem in low level vision in computer vision field. It is the key technology to process image analysis image comprehend and image depict successfully. Aim at measurement of granularity size of nonmetal grain a new algorithm of image segmentation and parameters calculation for overlapping grain image is studied. The hypostasis of this algorithm is present some new attributes of graph sequence from discrete attribute of graph consequently achieve that pick up the geometrical characteristics from input graph and new graph sequence which in favor of image segmentation is recombined. The conception that image edge denoted with "twin-point" is put forward base on geometrical characters of point image edge is transformed into serial edge and on recombined serial image edge based on direction vector definition of line and some additional restricted conditions the segmentation twin-points are searched with thus image segmentation is accomplished. Serial image edge is transformed into twin-point pattern to realize calculation of area and granularity size of nonmetal grain. The inkling and uncertainty on selection of structure element which base on mathematical morphology are avoided in this algorithm and image segmentation and parameters calculation are realized without changing grain's self statistical characters.