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1.
基于波波变换的多分辨图像融合   总被引:8,自引:0,他引:8  
图像的小波多分辨表征是把图像特征按度和方向映射到由波波变换系数构成的金字塔结构的各层中。在此数据结构中,使用不同的基于区域的特征选择方法,实现了对稆原始图像的明显特征的选择,包括基于能量和基于边缘检测的方法。  相似文献   

2.
基于小波变换的医学解剖与功能像融合新算法   总被引:1,自引:1,他引:0  
近年来,用于从多模医学图像数据中挖掘有用信息的融合算法不断被提出.但是,还没有一种合适的算法用于医学解剖和功能像的融合.基于此,提出一种基于小波变换的新方法,用于医学解剖和功能像的融合.选择高频系数时,通过计算各子图像的全局梯度来实现高频信息的融合,使融合后的图像较好地保留解剖结构所对应的功能信息;低频系数采用基于邻域能量的融合算法,保留解剖图像的边缘和纹理特征.实验结果和评价参数表明,这种改进的医学图像融合算法强化了融合图像的边缘和纹理特征,有效地保留了原图像的解剖信息和功能信息.  相似文献   

3.
摘要: 近年来,用于从多模医学图像数据中挖掘有用信息的融合算法不断被提出。但是,还没有一种合适的算法用于医学解剖和功能像的融合。基于此,提出一种基于小波变换的新方法,用于医学解剖和功能像的融合。选择高频系数时,通过计算各子图像的全局梯度来实现高频信息的融合,使融合后的图像较好地保留解剖结构所对应的功能信息;低频系数采用基于邻域能量的融合算法,保留解剖图像的边缘和纹理特征。实验结果和评价参数表明,这种改进的医学图像融合算法强化了融合图像的边缘和纹理特征,有效地保留了原图像的解剖信息和功能信息。  相似文献   

4.
基于小波变换的图像压缩算法在比特率较低时会出现重构图像边缘模糊现象.在充分考虑高频子带小波系数的分布特性对保存边缘、纹理等信息的影响之后,提出了一种新的基于势函数模糊聚类的方法来解决重构图像边缘模糊问题,实验结果显示:这种方法能较好地保存图像边缘和纹理信息,有效地减少边缘模糊现象和改善重构图像的主观质量.  相似文献   

5.
针对多聚焦图像融合问题,提出了一种新的基于提升静态小波变换(lifting stationary wavelet transform, LSWT)的多聚焦图像融合方法。对经LSWT分解得到的不同频域子带系数采用不同的系数选择方案。在融合低频子带系数时考虑到人眼视觉对图像局部对比度比较敏感的特性,引入了一种新的局部特征对比度的概念,并给出了低频子带系数的选择方案。在融合高频子带系数时,充分考虑到人眼视觉对图像边缘细节比较敏感的特性而对单个像素的亮度不敏感的特性,引入了一种适应于高频子带系数的特征对比度的概念,设计出一种基于特征对比度的系数选择方案。实验证明,算法相对于传统的基于图像对比度的图像融合方法,能够提取更多的有用信息并注入到融合图像中,得到视觉效果更好,更优量化指标的融合图像。  相似文献   

6.
基于改进二进制小波变换的图像边缘检测算法   总被引:1,自引:0,他引:1  
针对传统二进制小波变换在图像边缘检测应用中的不足,提出了基于改进二进制小波变换的图像边缘检测算法.该算法首先按水平、垂直和对角方向对图像进行改进的多尺度二进制小波变换,提取三个方向的小波系数,然后采用相邻尺度小波系数相乘的方法去除图像的噪声.再对去噪后的小波系数乘积极大值点进行检测,最后将这3个方向上的极大点进行融合,形成图像的边缘.  相似文献   

7.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通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;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

8.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通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;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

9.
在小波变换理论的基础上,提出了一种结合小波分解和脉冲耦合神经网络(PCNN)的遥感图像融合新方法.首先对两幅已经配准的原始遥感图像进行小波多尺度分解,得到低频子带系数和各带通子带系数;其次对低频子带系数采取一种基于边缘的方法以得到融合图像的低频子带系数;对各带通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;最后通过逆小波变换重构图像得到融合后的图像.仿真结果和评价指标结果表明,此方法更好地保留了原图像中的有用信息,提高了融合图像的质量.  相似文献   

10.
提出了一种基于WT和NSCT的复合医学图像融合算法。首先,对原始图像采用NSCT变换获得各方向的低频分量和高频分量,然后计算图像之间的相关系数,采用NSCT根据不同分解层的方向特征,对高频系数根据方向区域进行能量融合。最后,重新组合融合后的高频和低频分量,采用反变换的NSCT得到最终的图像融合结果。实验表明了该方法能完好保留原始图像的边缘和过渡区域信息,具有较好的细节表征能力和融合效果。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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