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1.
针对在噪声水平比较高的情况下难以从噪声图像本身提取准确先验信息的问题,提出一种从外部干净图像数据集学习非局部自相似先验信息的图像去噪方法。首先用高斯混合模型学习外部干净图像的非局部自相似先验信息,其次利用最大后验概率估计的方法找到与噪声图像块最匹配的外部先验信息,最后利用外部先验对噪声图像块进行稀疏表示。实验对比表明,所提算法在去除噪声的同时可以较好地保留图像的细节信息,使图像数据集的平均峰值信噪比提高0.18 dB以上。  相似文献   

2.
局部变分有效地增强图像的轮廓信息,但不可避免地模糊图像的细节并在平滑区域产生阶梯效应。非局部变分能有效重构图像的纹理信息,但同时会破坏图像的结构轮廓信息。考虑到局部与非局部变分的互补性,提出了一种基于图像局部梯度与非局部梯度的复合变分模型,并通过Bregman交替迭代极小化图像的局部梯度与非局部梯度的L1范数,使去噪后的图像在去除噪声的同时更好地保留图像的结构与细节信息。对比实验证明,提出的复合变分模型有效地利用了图像的局部变分与非局部变分的优点,在图像评价的主客观方面都表现出了更好的性能。  相似文献   

3.
针对统计非局部均值滤波损坏图像的细节与鲁棒性双边带滤波去噪不充分的缺点,提出了一种基于统计非局部均值滤波与鲁棒性双边带滤波相结合的复合滤波算法。该复合滤波算法通过统计非局部均值滤波与鲁棒性双边带滤波线性组合,利用Stein无偏风险估计对复合算法中的参数进行估计。实验中,从主观与客观方面进行对比分析,证明所提出的复合算法体现了非局部均值滤波与双边带滤波的优点,能有效地去除噪声并更好地保留图像的细节信息,峰值信噪比提高1~2 dB。  相似文献   

4.
合成孔径雷达(SAR)目标分类是自动目标识别系统的核心功能之一,对于战场监视等应用具有重要意义。利用SAR图像局部散射明显的特点,提出了通过训练样本的非负矩阵分解获得低维数局部特征编码,并以该编码作为字典进行稀疏表示分类的方法。采用Gotcha项目民用车辆目标的实测数据进行了验证,结果显示在不同信噪比条件下该方法的分类正确率均优于广泛采用的由降采样、随机投影、主成分分析提取低维数特征的稀疏表示分类方法,表明了该方法的性能优势。另外,还通过实验对比分析了非负约束的稀疏表示与标准稀疏表示在分类性能上的差别,结果显示非负约束的稀疏表示导致分类正确率下降,故针对分类问题不宜在稀疏表示时进行非负约束。  相似文献   

5.
李建国 《中国电子商务》2010,(12):129-129,131
介绍了小波包去噪的基本原理和方法,针对无线电信号的特点,采用四种闽值法进行去噪对比实验,去噪后信号的波形较为光滑,信噪比均有提高,均方差误差明显降低,有效地去除信号中的噪声,达到了保留信号特征,抑制噪声的目的,为无线电传输提供更可靠的数据信息。  相似文献   

6.
针对图像稀疏重建中因使用固定参数的全变分(TV)正则项所带来的图像细节缺失和阶梯效应问题,提出了一种自适应二阶广义全变分(TGV)约束的图像稀疏重建算法。该算法采用二阶广义全变分模型权衡图像的一阶导数和二阶导数,且能够根据每次迭代得到的重构解及对应张量函数自适应地修正权重系数,实现图像的稀疏重建。与全变分正则模型和固定参数广义全变分正则模型相比,该算法能更好地保持图像轮廓和细节信息,提高重建图像的峰值信噪比(PSNR)和结构相似度(SSIM)。  相似文献   

7.
梯度模值较易受到外界影响,导致全变分模型在大噪声点处往往不能很好地消除噪声,从而产生阶梯效应。针对该问题,提出了一种基于卷积运算与全变分模型的图像去噪方法。首先,针对以扩散形式获得的图像像素点进行卷积运算,利用滤波去噪降低大噪声点的灰度值;其次,以能量泛函形式构建图像全变分模型,并求解泛函对应的拉格朗日方程极小值来实现图像去噪;最后,将去噪后图像作为双边滤波算法的引导图像进行二次去噪,从而进一步提升图像去噪质量。仿真实验结果表明,与经典方法相比,该模型对去噪过程中的阶梯效应问题具有较好的处理效果。  相似文献   

8.
在图像处理和图像分析领域中,去除噪声是一个长期存在的问题。好的去噪方法为图像的后继处理如边缘检测、图像分割、图像匹配等会带来许多好处,为此,人们提出了许多图像去噪平滑的方法。  相似文献   

9.
针对雾霾天气条件下大气散射和悬浮颗粒物引起的图像对比度、清晰度降低问题,提出通过采用独立分量分析(ICA)算法分解图像中具有相互独立分量的混合像元,估计图像有用信息分量。因乘性噪声信息的存在,会导致估计的图像有用信息有一定的偏差;采用基于噪声检测的局部自适应中值滤波对估计的图像有用信息进行了进一步校正。实验结果证明:新算法能有效去除雾霾,提高图像的清晰度和对比度。  相似文献   

10.
离散小波变换(Discrete Wavelet Transform,DWT)通常用于图像的表示。然而,对于具有不规则形状边缘的图像,尤其是对于纹理和细节信息较多的遥感图像,DWT却很难有效表示,进而影响后续去噪效果。针对该问题,提出了一种基于图形小波变换(Graphic Wavelet Transform,GWT)的图像去噪方法。首先,将图像表示为图形信号,并通过该图形信号的谱表示构造相应的变换矩阵;然后,设计了一种改进自适应阈值的图像去噪方法,在GWT变换域内对图像去噪。实验结果表明,与常用的图像去噪方法相比,所提算法能够提供更好的图像主观质量。采用均方根误差(Root Mean Square Error,RMSE)和峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)作为客观指标,结果表明,采用所提方法得到的重建图像客观质量更优。  相似文献   

11.
Holding 88 percent of train media resources across China, based on "Time Cube", on the 2008 Intermedia Recommendation and Introduction Meeting on December 19, 2007, HTC announced its high-profile strategy of tour marketing and tapping the immeasurable potentials on the train. Meanwhile, HTC officially launched its brand new product Olympic Train on the meeting, providing a fabulous platform for all the brands that are prepared to do a smart marketing on the occasion of 2008 Olympic Games.  相似文献   

12.
In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport. With the addition of the two Chinese airlines, Star Alliance now has 19 member carriers operating 17,000 daily flights to 897 destinations in 160 countries.  相似文献   

13.
Under the guidance of the theme slogan of the 29th Olympic Games - One World One Dream, with dream, love and dedication as its theme, the 2008 Music Grand Ceremony & 1000 People Charity Concert on 100 days cotmtdown to Paralympic Gamesis officiaily launched on December 22, 2007. The 2008 Music Grand Ceremony is sponsored by China Disabled Persons' Federation, and co-hosted by National Paralympic Committee of China,  相似文献   

14.
MUYANG GROUP     
With its headquarters in the historic city of Yangzhou,Jiangsu Muyang Group Co.,Ltd has since its founding in 1967 grown into a well-known group corporation whose activities cover research & development,project design,manufacturing,installation and services in a multitude of industries including feed machinery and engineering,storage engineering,grain machinery and engineering,environmental protection,conveying equipment and automatic control systems.  相似文献   

15.
Aseries of events that occurred in October 2007, are rewriting the history of China's energy industry: November 3 an Energy Law Committee asked the public for suggestions on improvements; forty top experts came together to form the National Energy Expert Advisory Committee on November 6; and the National Oil Reserve Center (NORC)became the nerve centre of oil reserves on November 18. Yet, behind the progress of these recent activities remains the fact that international oil prices still hover around a very high price of US$ 90/barrel, and China's oil imports are close to accounting for half of its total oil reserves.  相似文献   

16.
2007 China Harbor Ten People elected the entrepreneurs who contributed a lot to port economy and enterprises this year trough their talent management.These ten people embody their social responsibility,professional skills,creative ability,and charming personality.Bearing full confidence in China's port economy,the port entrepreneurs are brave enough to explore a brand new area,so as to promote harbor economic development. At the very beginning of 2008,China Shipping Website,Dalian Maritime University,and China Port and Shipping In- stitute jointly select the 2007 China Harbor Ten People,demonstrate port entrepreneurs' stunning minds,disclose their secrets to success,and providing abundant experiences to others in harbor development.The top ten people are various excellence during the ups and downs harbor development.  相似文献   

17.
Since the normalization of the diplomatic ties between China and ) Japan, the bilateral economic relations have deepened continually. According to the statistic of Japan, China passed U.S. to become Japan's top trade partner as well as is the second largest export market for Japan and is the largest import resource for Japan. Japan companies such as Mitsui, Sumitomo, Sony and Panasonic, have set the subsidiaries in China and explored their scales. This year 2008 marks the 30th anniversary of the signing of the ChinaJapan Treaty of Peace and Friendship.  相似文献   

18.
China's textile and apparel industry suffered an unprecedented cold market for exports in the first quarter this year,the result of a few factors including: the appreciating RMB, decreasing export rebate rate,expanding influence of the U.S. subprime crisis, increasing costs of production and rising labor cost.  相似文献   

19.
The May 12 earthquake in Sichuan caught Chinese people by surprise and took the nation's heart. While mourning the dead and searching for the missing, many services must be provided for the survivors in the wake of the earthquake. Available post-quake financial services have become an important part of the reconstruction effort in the disasterstricken areas of Sichuan province.  相似文献   

20.
Aristotle saw ethics as a habit that is modeled and developed though practice. Shelly's Victor Frankenstein, though well intentioned in his goals, failed to model ethical behavior for his creation, abandoning it to its own recourse. Today we live in an era of unfettered mergers and acquisitions where once separate and independent media increasingly are concentrated under the control and leadership of the fictitious but legal personhood of a few conglomerated corporations. This paper will explore the impact of mega-media mergers on ethical modeling in journalism. It will diagram the behavioral context underlying the development of ethical habits, discuss leadership theory as it applies to management, and address the question of whether the creation of mega-media conglomerates will result in responsible corporate citizens or monsters who turn on their creators.  相似文献   

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