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1.
传统的一些去噪技术往往是以牺牲图像的边缘和细节为代价的.为了去掉图像的噪声,同时又能够很好地保留图像的边缘和纹理细节,在介绍第二代小波变换的原理的基础上,提出使用边缘检测的方法检测出图像的边缘和纹理细节,将它和该图像进行融合,用第二代小波对含噪图像进行分解,对图像高频进行自适应去噪.由于图像在去噪前融合了边缘信息,因此边缘和细节部分得到了增强.仿真结果表明:该去噪方法优于传统小波阈值去噪方法.  相似文献   

2.
将对数图像处理数学模型应用到图像还原中,采用全变分的方法获得了去除图像乘性噪声的新模型.该模型弥补了现有图像去噪方法的不足,很好地保持了图像的边缘细节特征,并具有与人眼视觉特征相吻合的特点.仿真实验结果表明,与现有的去噪方法相比,新模型很大程度上减小了图像在去噪处理迭代过程中产生的误差,不仅去噪效果更好,而且能很好地保...  相似文献   

3.
图像隐含的低秩先验特性已被成功应用于去噪等图像恢复应用.考虑到自然图像具有的非平稳特性以及迭代重构中图像噪声强度的变化,提出了一种结合近似消息传递与自适应低秩去噪的图像压缩感知重构方法.根据迭代重构图像的噪声方差估计,自适应地调整分块图像的大小以及相似块组的规模,实现低秩去噪性能的有效提升,从而保证了迭代重构的收敛速度,并同时改善了重构图像的质量.大量实验结果表明:该方法在无噪和有噪观测环境下都具有较好的重构性能,且能够有效地保留图像的纹理细节信息.  相似文献   

4.
提出了一种新颖的图像多尺度几何变换方法,主要由预处理、方向滤波器组和最优方向小波变换等组成.方向滤波器组将预处理后的高频分量分解为多个方向子带,然后每个方向子带执行改进的最优方向小波变换.该变换兼有Bandelet变换和Contourlet变换的多尺度几何分析特性,能更稀疏地表示边缘和纹理特征.分别将EBCOT编码和硬阈值去噪应用到图像变换系数中,从而实现了有效的图像压缩和去噪,很好地保护了图像细节.实验结果表明,对于纹理和边缘丰富的图像,所提出的图像压缩和去噪方法在视觉质量上明显优于基于Bandelet或Contourlet变换的方法,峰值信噪比也提高了0.1 dB以上.  相似文献   

5.
基于Gabor滤波器的图像去噪研究   总被引:1,自引:0,他引:1  
Gabor滤波器具有良好的尺度特征和方向特征,与人类视觉系统的特性相吻合.实验结果表明Gabor滤波器能够对图像进行去噪,并能很好地保护图像的细节,具有更好的视觉效果.  相似文献   

6.
提出了一种基于高斯比例混合模型的图像Curvelet域去噪算法,改善了图像的去噪效果.首先对图像进行Curvelet变换.然后建立系数邻域的高斯比例混合模型.最后在模型基础上用贝叶斯最小二乘估计方法对系数进行估计.算法有效结合了Curvelet变换对图像边缘的高效表示能力和高斯比例混合模型对邻域系数相关性的概括能力.实验结果表明,在主观视觉上.该算法对图像边缘进行了很好的保护;在峰值信噪L-'c上较其他算法也有所改善;特别是对纹理细节比较丰富的图像.去噪效果更加明显.  相似文献   

7.
一种基于小波变换图像去噪的新方法   总被引:2,自引:0,他引:2  
提出一种将小波变换去噪和高阶统计量滤波法去噪相结合用于图像去噪的新方法, 既较好地保持了图像边缘细节, 又有效地虑除了噪声. 实验结果表明, 相对于单一的小波变换去噪或高阶统计量滤波法去噪, 所给方法在视觉和峰值信噪比增益上都取得较好效果.  相似文献   

8.
针对PCA-NLM去噪方法容易丢失图像纹理细节的问题,提出一种基于纹理特征描述的改进PCA非局部均值去噪方法.基于局部结构张量的边缘纹理描述将图像划分为平坦区、边缘区和纹理区,根据边缘纹理特征值自适应地选取PCA维数和搜索区域以改进去噪效果.实验结果表明,该方法对纹理细节丰富的区域能更好地保留了图像纹理细节,降噪效果优于PCA-NLM方法.  相似文献   

9.
针对煤矿井下岩层监视监控系统中图像模糊的问题 ,提出了采用小波变换进行图像增强处理 .通过分析了一种基于Mallat的传统的小波变换的图像增强方法 ,提出了综合利用基于小波变换的阈值化去噪方法和计算增强系数的实用算法来实现含有噪声图像增强的算法 .通过实例综合利用基于小波变换的阈值化去噪方法和计算增强系数的实用算法 ,实现了对煤矿井下锚杆钻孔内岩层图像的增强处理 .研究结果表明 ,基于小波变换的图像增强方法能够较好地增强煤矿井下锚杆钻孔内图像中的细节特征 ,从而获得了比较满意的视觉效果 .  相似文献   

10.
为了改善小波阈值去噪算法中硬阈值和软阈值存在的不足,提出一种新的小波阈值去噪方法.该算法在进行小波阈值去噪前,先将图像分割成背景平坦区域和细节区域两部分,然后分别进行小波阈值去噪,最后融合两图像从而获得去噪图像.在分别进行小波阈值去噪时,利用迭代法进行阈值选择,采用"软、硬阈值折中"阈值函数.根据对医学图像去噪的仿真实验结果表明,该算法在去噪效果上均优于传统的软硬阈值方法.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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