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1.
针对全变差(TV)正则化图像复原其细节恢复能力有限且对噪声敏感等问题,本文利用多方向边缘检测,对传统TV模型进行改进,得到基于边缘检测的多方向加权TV模型;为了使复原模型更具普适性且提高细节恢复能力,本文将暗通道先验融入上述模型,提出基于暗通道先验和多方向加权TV的图像盲去模糊方法.同时,在模糊核估计过程中,提出了基于自适应强边缘提取的模糊核估计方法,可有效剔除伪边缘、噪声等不利信息,使模糊核估计更具鲁棒性;最后,给出了模糊核估计和去模糊模型的最优化求解算法.实验结果表明,本文方法可准确估计模糊核,复原图像含有更丰富的边缘、纹理等细节特征.  相似文献   

2.
在图像盲去模糊中,从单一模糊图像估计模糊核是个严重不适定问题.文中提出了一种基于稀疏先验和相对总变分的图像盲去模糊方法.该方法用权值L0平滑方法自适应地提取图像主体结构,剔除图像噪声、细节和小尺度物体边缘等不利于模糊核估计的因素;用相对总变分方法解决稀疏先验作为正则项估计复杂模糊核所存在的不准确性;用超拉普拉斯先验的正则化方法进行清晰图像估计.实验结果表明,文中算法相对于现有的图像去模糊方法,所估计出的清晰图像具有较好的结构和较少的伪迹,图像复原效果好.  相似文献   

3.
为了有效地对立体视觉双目模糊图像进行复原,提出一种动目标双目图像MAP的优化复原方法,将双目运动模糊图像的复原问题转化为在模糊核路径关系约束下的双重循环MAP优化估计问题,在保证模糊核路径对应关系前提下,对双目图像进行去模糊。建立了双目图像模糊核路径的对应关系模型,将关系模型作为约束条件式,嵌入到基于模糊核和双目原图像的MAP优化估计过程中,通过双重循环迭代获取双目图像的模糊核和清晰图像。实验结果表明,该方法能够有效地去除立体视觉双目图像的模糊。  相似文献   

4.
在图像去模糊问题中,图像的模糊核估计是重中之重.通常图像的梯度服从重尾分布这一先验被广泛的运用于图像的模糊核估计中,然而受限于非凸优化的数值求解方法,人们往往采用图像梯度的L1范数或者L2范数来近似,从而构造出计算较为简单的凸优化能量函数来估计模糊核.为此,本文提出一种基于Lp稀疏正则的非凸优化的模糊核估计方法,该方法以服从超拉普拉斯分布的图像梯度的Lp范数为稀疏先验项,有效的提高了先验知识的准确性的同时增强图像的强边缘,抑制了细小边缘对模糊核估计的影响.在对Lp范数的数值求解问题中,本文采用GISA(generalized iterated shrinkage algorithm)可以简单且有效的求得任意p值下的最优解.实验表明与传统方法相比,本文方法有效地提升图像的质量,去模糊后的图像更加清晰.  相似文献   

5.
散焦含噪图像的点扩散函数估计与边缘检测   总被引:3,自引:0,他引:3  
针对机器视觉中图像模糊的原因,采用广义高斯函数描述点扩散函数(PSF),建立边缘扩散模型,从一幅图像所含的多条边缘中提取样本,依据提出的整合准则从全部样本的估计结果中计算整幅图像的PSF,利用最优求解的概念,在最小二乘近似下实现PSF及亚像素级边缘位置的最佳估计.实验结果表明,由于获得了图像对应的PSF最佳估计,因此边缘检测具有比较高的抗噪性能,在边缘亚像素检测基础上完成的尺寸测量误差小于0.5%.  相似文献   

6.
目标运动场景去模糊问题是一个具有挑战性的病态逆问题,这是因为在动态场景中不同目标和背景区域可能会存在不同的模糊核.现有的基于能量优化的去模糊方法是将模糊图像分割成具有不同模糊度的多层图像,然后对不同的模糊层进行去模糊处理,然而其优化方案往往涉及迭代,耗时又烦琐.针对目标区域与背景区域可分离的模糊场景,结合传统的基于能量优化和基于深度学习方法的优点,提出一种基于深度对抗网络和局部模糊探测的目标运动场景去模糊模型,该模型由三个生成网络组成,用以建模潜在清晰图像、模糊核和模糊图像的权重变量.模型采用深度图像先验(Deep Image Prior,DIP)作为潜在清晰图像的正则化项,使用非对称跳跃连接自编码器生成潜在图像;采用全连接网络(Fully-Connected Network,FCN)生成模糊核.为了准确地获取模糊图像的分割结果,提出三条准则来指导权值变量网络结构的设计.实验结果表明,该方法同其他传统方法相比可以显著地提升重构性能,视觉效果更好.  相似文献   

7.
针对传统全变差(TV)去模糊对噪声敏感且细节恢复能力有限等缺点,利用边缘检测对传统TV模型进行改进,并受空域非局部自相似性正则化思想启发,将图像的变换域非局部自相似性约束融入去模糊模型,提出一种基于边缘检测的多方向加权TV和变换域非局部正则化的图像去模糊方法.首先,运用边缘检测将中心像素邻域内的像素对划分为同侧像素对和异侧像素对,对不同类型的像素对采用不同的权重,在去模糊的同时尽可能保持图像边缘等细节特征;其次,为充分利用先验信息,将变换域非局部正则化约束融入到改进的TV模型,进一步改善图像视觉质量;最后,对新模型进行有效求解.实验结果表明,本文算法在去模糊的同时可更好地保留图像的边缘、纹理等细节特征.  相似文献   

8.
针对机器视觉中图像模糊的原因,采用广义高斯函数描述点扩散函数(PSF),建立边缘过渡区模型,从一幅图像所含多条边缘中提取样本,依据提出的整合准则从全部样本的估计结果中计算整幅图像的PSF,利用最优求解的概念,可实现最小二乘意义下PSF及亚像素级边缘位置的最佳估计。实验结果表明, 由于算法获得图像所对应PSF的最佳估计,边缘检测具有比较高的抗噪性能,在边缘亚像素检测基础上完成的尺寸测量误差小于0.5%。  相似文献   

9.
运动模糊图像的盲复原在现有的方法中多数针对灰度图像,而彩色图像是由多个图层耦合而成,将彩色图像转化为灰度图像过程中必然会造成信息丢失。针对彩色图像的去模糊问题,提出多尺度框架下,将曲率项对彩色图像的边缘保护特性和归一化的曲率项的正则化约束相结合,在彩色图像各个通道上由粗尺度到细尺度估计模糊核,采用多通道全变分模型(Multi-channel total variation,MTV)进行图像复原。为降低去模糊方程的求解复杂度,求解时引入快速分裂(Split Bregman)算法。实验结果表明,尽管曲率项会加大算法的计算量,但是复原后的图像细节效果更明显,质量更好。  相似文献   

10.
为在图像模糊核估计中充分利用图像的区域特征和结构信息作为先验知识,提出一种基于马尔科夫随机场学习模型的模糊核估计方法.首先,由滑动的子窗口构成马尔科夫随机场的节点集,以每个子窗口的曲率方向能量滤波器的响应和边缘分布组成的特征向量作为模型的输入;然后,利用对数伪似然优化算法估计模型参数,在模型训练阶段,采用交叉熵相似性度量模糊核的相似性以标记训练样本;最后,利用置信度传播算法推测最优图像子块.运用所提方法对仿真和实际模糊图像进行实验,结果表明,该学习模型可以精确地估计模糊核,在主观视觉对比和客观评价方面均具有较好的效果,同时也具有较好的自适应性.与其他3种方法相比,模糊核相似度分别提高了1.55%,5.64%和7.02%.  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.
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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

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.
19.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

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