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 78 毫秒
1.
提出了一种新的基于非下采样轮廓波(NSCT)和脉冲耦合神经网络(PCNN)相结合的自适应图像融合方法.对已经配准的源图像进行NSCT分解,得到低频子带系数和不同方向的高频子带系数.对NSCT分解的低频部分采用简单的加权平均融合规则;而高通子带系数,采用改进的拉普拉斯能量作为PCNN链接强度的方法.最后,对融合的系数进行NSCT逆变换得到融合图像.实验结果表明,本文算法明显优于其他几种方法,具有更好的融合性能,清晰度更高,是一种可行、有效的图像融合方法.  相似文献   

2.
基于区域特性的NSCT多聚焦图像融合新方法   总被引:2,自引:1,他引:1  
本文提出了一种基于区域特性的NSCT多聚焦图像融合新算法。首先将待融合图像用NSCT分解成不同尺度,不同方向上的子带;然后对分解后的高频系数采用基于区域能量的方法进行融合,对低频系数采用基于区域方差的方法进行融合;最后将融合后的系数进行NSCT反变换得到融合后的图像。实验结果表明基于区域特性的NSCT图像融合方法优于其他传统方法,验证了本文算法的合理性。  相似文献   

3.
针对医学图像融合存在伪影、边缘保持性弱等问题,提出了一种参数自适应的脉冲耦合神经网络(pulse coupled neural network,PCNN)图像融合方法。首先,对源图像通过非下采样Contourlet变换(non-subsampled contourlet transform,NSCT)得到一个低通子带和多个尺度多个方向下的带通子带。然后用区域标准差调整连接范围,进而调整突触权重矩阵以及加权系数;用各子带的改进空间频率中方向特征最显著的分量调整连接强度;对于外部激励,低通子带用区域能量和区域方差的线性组合计算,带通方向子带采用改进的拉普拉斯能量和计算。点火映射图的判决遵循取大原则。最后,通过NSCT逆变换得到融合结果图。实验结果表明,此算法能更多地保留源图像的信息,边缘保持能力更强,融合图像对比度高,视觉效果更佳,适用于多种模态医学图像之间的融合。  相似文献   

4.
针对NSCT变换算法具有较高复杂度、计算时间长、不符合实时性要求的问题,提出将基于Shearlet变换和稀疏表示的算法引入到遥感图像融合中。首先,对待融合图像进行Shearlet变换,分解后得到的低频子带系数采用区域能量取大的融合规则;分解后的高频子带系数采用PCNN的融合规则,最后对重构系数进行Shearlet逆变换。实验结果表明,与NSCT变换及经典算法相比,新方法不仅有效改善了图像融合质量,同时提升了算法的运行速度,实时性良好。  相似文献   

5.
基于NSCT-PCNN变换的多传感器图像融合   总被引:1,自引:1,他引:0  
针对同源和异源的多传感器图像的特征,提出了一种基于非下采样Contourlet变换(NSCT)和脉冲耦合神经网络(PCNN)的新的图像融合算法。首先,用NSCT对已配准的源图像进行分解,从而准确地提取出了二维和更高维的边缘纹理信息;其次,对低频子带系数采用区域方差进行了整合,从而得到融合图像的低频子带系数,而对高频子带系数提出了一种改进的基于PCNN的图像融合方法来确定融合图像的各带通子带系数;最后通过对所有子带系数进行NSCT逆变换,从而得到了融合图像。实验结果表明,该方法优于Mallat小波方法和传统的NSCT方法,有更好的视觉效果。  相似文献   

6.
提出一种应用非下采样contourlet变换(nonsubsampled contourlet transform,NSCT)进行图像检索的算法,以获取一种兼顾纹理图像概貌和细节信息的特征,从而提高图像检索的性能.该算法利用NSCT对图像进行多尺度、多方向分解,获得子带系数矩阵;对低频子带系数提取能量和方差作为全局纹理特征,并对高频子带系数分别提取尺度间和尺度内纹理信息;通过非高斯双变量模型拟合子带系数,利用信息熵描述尺度间特征;尺度内特征通过对同一层子带图像按主方向排序,获得直方图图像,计算其加权信息熵作为特征向量.对Brodatz标准纹理库的检索实验结果表明,与同类算法相比,该文方法具有更高的检索性能.  相似文献   

7.
临床辅助诊断对医学图像视觉效果提出了较高的要求,但非下采样轮廓波变换(NSCT)分解获得的低频子带系数不具有稀疏性,不利于保持源图像的细节信息。针对上述问题,提出了一种结合稀疏表示与脉冲耦合神经网络(PCNN)的医学图像融合算法。首先,通过NSCT将源图像分解成低、高频子带系数;其次,利用K奇异值分解(K-SVD)法训练低频子带系数获取过完备字典D,利用正交匹配追踪(OMP)算法稀疏编码低频子带系数,完成低频子带稀疏系数的融合。然后,利用高频子带的空间频率激励脉冲耦合神经网络,根据点火次数选择高频子带的融合系数。最后,将融合的低、高频子带系数通过NSCT逆变换重构出融合的医学图像。实验结果表明:对于边缘信息传递因子Q~(AB/F)指标,该算法灰度和彩色图像融合结果相比于对比算法约提升了34%和10%,且融合结果综合性能优于现有算法。  相似文献   

8.
提出一种把非下采样Contourlet变换(NSCT)和区域特征相结合的图像融合新方法.该方法能够获取更好的空域和频域中的局部特征,同时提高融合图像的质量.用NSCT对已经配准的源图像在不同尺度和方向进行分解,低频子带分量采用区域平均能量和匹配度相结合的融合规则,高频子带分量使用改进的拉普拉斯能量和取大的融合规则.然后,利用逆NSCT变换对图像重构得到融合结果.实验结果表明,新方法优于其他三个常用的方法,且较好地保留图像的边缘和细节信息.  相似文献   

9.
针对红外图像对比度低、噪声大等特点,提出一种基于改进的直方图均衡化和NSCT变换(nonsub sampled contourlet transform)相结合的的红外图像增强方法。首先对红外图像进行NSCT变换,得到多尺度多方向的高频子带系数和一个低频子带系数。高频子带首先采用自适应降噪函数降低高频系数的噪声同时很好地保护边缘信息,然后采用非线性增益函数调整高频分量;在低频分量上采用改进的直方图均衡化方法进行增强。最后经NSCT逆变换得到增强图像。实验结果表明,提出的算法可以有效地提高红外图像的对比度,抑制图像的噪声,增强图像对比度,突出图像的边缘轮廓信息。  相似文献   

10.
采用SCDPT变换对图像进行多尺度、多方向分解,得到图像不同尺度、不同方向的频带系数.然后对低频子带系数采取基于结构相似性(SSIM)、区域能量和区域平均梯度的融合规则,对方向子带系数采取基于SSIM和区域方差的融合规则.最后通过SCDPT逆变换得到融合图像.采用信息熵、平均梯度、互信息、边缘强度、均值等作为客观评价指标,实验结果表明,相对于小波变换、拉普拉斯金字塔变换、梯度金字塔变换,所提出的算法能够充分提取图像特征,具有更灵活的方向性和平移不变性,并且能够准确捕获图像轮廓特征信息和纹理细节信息.融合结果优于大部分基于其他多尺度变换的图像融合算法.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  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