首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
陶宇  苗华  杜双  王文生 《半导体光电》2013,34(5):890-894,898
复杂背景的低对比度目标识别一直是目标探测跟踪的关键技术之一。针对光电混合联合变换相关器,以多小波变换为基础,应用GHM多小波对目标联合图像处理,并采用多尺度非线性方法,通过非线性函数有效地改变各尺度上的细节分量,从而改变图像对比度,达到增强目标图像的目的。对复杂背景的低对比度目标图像进行了大量计算机模拟实验和光学相关实验,结果表明,这种基于多小波图像增强算法,对复杂背景的低对比度目标能够获得明亮的相关点,提高低对比度目标的识别率。作为实例,文中给出航行中低对比度船的图像识别。  相似文献   

2.
为了提高联合变换相关器对复杂背景下的低对比度目标的识别能力,提出了小波变换与灰度拉伸以及Canny算法相结合的物面滤波新方法,并设计了新物面处理滤波器.通过计算机模拟和光学实验证明,该方法可以准确地提取目标特征,有效地降低噪声并最终获得明亮的相关峰,成功解决了低对比度复杂背景目标的识别问题.  相似文献   

3.
联合变换相关器在识别复杂背景中的低对比度目标时,由于背景噪声的干扰,相关峰的对比度明显降低,甚至得不到相关峰.将反色技术应用到联合变换相关器的物面图像处理中,可以使信号能量突出,同时抑制背景噪声,提高实时联合变换相关器物面的有用信息衍射光的能量,从而使得相关峰对比度增强,实现目标的自动探测、识别和定位.因此反色技术在复杂背景目标探测与识别中有着重要的作用.  相似文献   

4.
基于相关的多重分形奇异性分析的红外弱目标检测   总被引:4,自引:0,他引:4       下载免费PDF全文
针对红外图像中的目标对比度低、背景复杂及受噪声严重干扰等特点,利用象素之间的相关性,提出了一种基于相关多重分形奇异性分析的弱目标检测方法.实验结果表明该算法对海洋和天空复杂背景及随机噪声影响都具有较好的抑制作用.  相似文献   

5.
低对比度图像具有邻近像素的空间相关性高、灰度变化不明显等特点,从中分割出微小目标是非常困难的。本文提出一种新的低对比度图像提取小目标的分割算法,通过引进局部均匀度,结合局部熵获得空间分布状态,对低对比度图像进行分割,该算法充分利用了目标图像的灰度和空间属性。实验结果表明,该方法能有效地实现低对比度小目标图像的分割。相对于其他算法,分割精度更高,且抗噪性强,可以有效地降低过分分割问题。  相似文献   

6.
基于模板的低信噪比前视红外建筑物识别技术   总被引:1,自引:0,他引:1  
针对低信噪比复杂地物背景下的前视红外地面建筑物目标自动识别问题,提出了一种基于目标模板的自动目标识别方法。首先,根据制备模板的尺度和形状信息对实时图像进行形态学背景抑制增强和目标重构处理;然后,对重构后的图像进行垂直和水平边缘线条提取和轮廓匹配,融合垂直和水平线条匹配结果得到最终的相关峰和潜在目标区域;接着,根据目标模板对潜在目标区域进行区域灰度对比度度量;最后,融合轮廓匹配和区域灰度对比度度量结果,得到最终相关峰,实现目标的识别。大量数据测试表明,该方法的正确识别率在92%以上,定位误差小于2个像素,速度快、检测性能好、适应性较强、易于硬件实现。  相似文献   

7.
一种快速递归红外舰船图像分割新算法   总被引:4,自引:4,他引:4  
针对背景复杂、对比度低的红外舰船目标分割问题,提出了一种红外舰船图像分割的新算法.由于二维最大类间方差法不仅反映了图像的像素点灰度分布信息,还反映了邻域空间相关信息,因此有较好的抗噪能力.但是由于其解空间维数的增加,计算量的变化是以指数增长的,而粒子群优化算法可实现高效并行、随机、自适应群体搜索.基于这一特点,提出了基于粒子群优化的二维最大类间方差局部递归分割方法,有利于实现红外图像的实时处理.该方法同样适用于复杂背景下的其他红外目标图像的分割.  相似文献   

8.
郑成勇 《红外》2006,27(9):13-15
根据海空背景下的红外图像特性,设计了一种新的对噪音鲁棒的目标背景对比度增强方法。在此基础上提出了一种基于目标局部能量正态分布的自适应目标提取方法。实验结果表明了算法在对红外斑点目标进行单帧提取时的精确性和高效实用性。  相似文献   

9.
一种基于小波变换的非线性红外图像增强算法   总被引:1,自引:0,他引:1  
针对红外图像对比度低,噪声干扰大,用传统增强算法增强时,增大噪音的问题,提出了一种基于小波变换的非线性红外图像增强算法.该算法先对原始图像进行小波变换获得低频和高频系数,接着根据低频系数的特点设计了非线性函数对低频系数进行增强,并对高频系数进行小波去噪,最后通过小波重构得到增强的图像.仿真实验表明,该方法不仅解决了红外图像对比度低的问题,并且降低了噪声,突出了图像细节,该方法无论是增强效果还是抗噪效果都明显优于传统的图像增强方法.  相似文献   

10.
一种低信噪比运动点目标检测算法   总被引:4,自引:0,他引:4  
卓宁  孙华燕 《激光与红外》2004,34(6):484-486
为检测复杂背景中的低信噪比(SNR) 点目标,提出了一种自适应带通门限检测算法。 首先根据图像的信噪比选取合适的带通门限进行图像空间滤波,然后采用帧相关法进行时间滤波。实验结果表明,该算法可有效地抑制背景杂波的干扰、提高信噪比SNR ,检测出复杂背景下的低信噪比点目标,且易于实现。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

16.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

17.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

18.
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.  相似文献   

19.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

20.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号