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1.
基于内容的图像检索系统的实现   总被引:1,自引:1,他引:0  
廖倩倩 《电视技术》2007,31(2):90-93
将小波变换有效地运用于对图像的颜色和纹理特征的提取,并提出了一种将小波变换与图像分块结合起来提取颜色特征的方法,开发出一个综合运用颜色、纹理特征及相关反馈技术进行图像检索的系统。实验结果表明,该系统具有明显的优越性和通用性。  相似文献   

2.
为了提高医学图像检索的正确率,提出一种局部线性嵌入算法和相关反馈相融合的医学图像检索方法(LLE-MF)。首先根据方块编码的思想提取颜色分量的信息熵,并利用邻域灰度共生矩阵提取纹理特征;然后采用局部线性嵌入算法对颜色和纹理特征进行组合、降维处理,并采用欧式距离相似度量模型对图像初步进行检索,最后采用最小二乘支持向量机对初步检索结果进行相关反馈,并进行仿真测试。结果表明,相对于其他医学检索算法,LLE-MF不仅提高了医学图像的检索准确率,而且提高了医学图像的检索效率,可以准确地找到用户所需的图像。  相似文献   

3.
党妮  胡方明  曹越 《电子科技》2012,25(12):137-140,150
通过对图像进行特征提取的方法,设计并实现了一种基于小波纹理特征的图像检索原型系统,并利用所获得的纹理特征对图像库进行检索。实验结果表明,小波变换是一种有效的纹理特征提取方法,能有效地提高检索的准确度。  相似文献   

4.
纹理图像检索的不同相似性度量方法的比较研究   总被引:1,自引:0,他引:1  
图像特征和相似性度量方法的选取是基于内容图像检索的一个关键环节。针对该问题,提出一种基于整数小波包分解的纹理特征检索方法。通过连接小波包分解后各尺度内和尺度闯不同频带的小波系数,提取标准方差和均值信息描述纹理。此外,对8种相似性度量方法进行了分析和比较。通过对纹理库的检索实验表明,与传统的距离测度相比,Canberra和Bray—Curtis距离测度能有效地提高图像的检索性能。  相似文献   

5.
图像检索是医学图像辅助诊断的基础,为了提高医学图像检索的正确率,提出一种流形学习和相关反馈相融合的医学图像检索算法(LLE-MF)。首先根据方块编码的思想提取颜色分量的信息熵,并利用邻域灰度共生矩阵提取纹理特征;然后采用非线性流形学习对颜色和纹理特征进行组合、降维处理,并采用欧式距离相似度量模型对图像初步进行检索,最后最小二乘支持向量机对初步检索结果进行相关反馈,并进行仿真测试。结果表明,相对于其它医学检索算法,LLE-MF不仅提高了医学图像的检索准确率,同时提高了医学图像的检索效率,可以准确地找到用户所需的图像.  相似文献   

6.
黎明  邢冬冬  汪宇玲 《电子学报》2019,47(4):962-969
针对Trace变换提取的图像特征缺乏对纹理边缘信息描述和计算代价高的问题,利用小波变换对图像轮廓的表征优势,提出了多分辨率Trace变换并应用于纹理图像分类.首先,将小波变换引入到Trace变换中,对纹理图像进行非下采样小波变换,得到不同频率的低频特征子图及高频边缘子图;其次,在各级子图上进行一组泛函的Trace变换,获取纹理图像的融合特征,在获得图像边缘信息的同时避免了Trace变换不同泛函组合计算代价过高的问题;最后,把融合特征送入支持向量机对图像进行分类.实验结果表明,对图像采用多分辨率Trace变换提取的融合特征具有更好的纹理描述能力,相对于传统Trace变换及MCM等对比方法具有更高的鉴别性能,且在时间效率上相对于传统Trace变换有大幅提升.  相似文献   

7.
纹理因素是描述图像的重要特征之一,为了准确地刻画纹理特征,增强图像的区分能力,该文提出一种基于双树复数小波域统计特征的纹理图像检索方法。首先对图像采用双树复数小波变换得到各子带系数,由于系数存在细微不完全对称分布特性,将其建模为双广义高斯模型。其次,因为各子带系数之间不完全独立也不完全冲突,存在不确定关系,所以采用模糊集合和证据理论(FS-DS)的方法,融合各子带系数特征。最后,对Brodatz和彩色纹理图像库进行仿真实验,并与多种统计建模的方法相比较。结果表明,该方法有效地提高了纹理图像的平均检索率。  相似文献   

8.
特征结合和相关反馈技术在医学图像检索中的应用   总被引:6,自引:0,他引:6  
本文在单一检索的基础上,对基于灰度直方图的颜色特征,基于小波变换的纹理特征和基于不变矩的形状特征进行融合.为了使用户能够参与检索过程,又引入了相关反馈机制,通过调整权值使得检索的结果最终满足用户的检索要求.最后分别给出基于单一特征,特征融合和相关反馈方法的查准率和查全率,并对试验结果进行分析.  相似文献   

9.
基于Radon和小波变换的图像检索   总被引:3,自引:2,他引:1  
提出一种基于Radon和小波变换的图像纹理特征检索算法.对原始图像进行坐标系的方向归一化,再对方向归一化后的图像进行Radon变换.根据Radon变换投影数据的几何特性,构造了适合投影数据的具有尺度和平移不变性的小波分解,该小波分解系数具有旋转、平移和尺度不变性.采用图像中各尺度小波系数的能量值作为图像的纹理特征,以此作为纹理特征进行图像检索.基于纹理特征的试验结果表明该特征具有旋转、平移和尺度不变性,与其他算法相比具有较高的检索率.  相似文献   

10.
基于语义的信息检索中的反馈技术   总被引:1,自引:0,他引:1  
首先分析了两种基于语义的信息检索系统的基本框架。由于相关反馈计算在基于内容的图像检索中受到广泛重视,因此对相关反馈中的加权距离进行了讨论和总结。这种相关反馈技术使得高层次语义特征能够逐步嵌入到低层次特征的图像检索中,使检索的准确率大大提高。  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.
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   

13.
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   

14.
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   

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.
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   

17.
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   

18.
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   

19.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

20.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

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