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1.
提出一种自适应方向提升小波变换算法.该算法将压缩的图像分成许多大小相等的子块.对每个子块,根据图像的统计特性(瞬时方差系数),自适应地选择提升方向和提升小波的类型.对方向信息较少的块,直接采用普通的水平和垂直提升.对方向信息较多的块,采用方向提升小波.实验结果表明;同DA-DWT算法相比,该算法能够显著降低方向小波变换的时闻,同时在低码率下,PSNR有所提高.  相似文献   

2.
林娜  倪林  刘权 《计算机工程》2011,37(21):199-201
提出一种基于自适应方向提升(ADL)小波变换的图像压缩算法。根据灰度共生矩阵角二阶矩的差异,将图像分割成平坦性不同的分块。对纹理信息较少的块,采用一般提升小波变换以减少变换时间。对纹理信息较多的块,采用方向提升小波以提高变换效果。结合多级树集合分裂编码和算术编码对变换系数和方向信息分别进行编码。实验结果表明,与ADL算法相比,该算法能有效减少方向小波变换时间。  相似文献   

3.
基于纹理的自适应提升小波变换图像压缩   总被引:4,自引:0,他引:4  
经典二维小波变换仅在图像的水平和竖直方向应用小波滤波,不能提供灵活的方向信息,对纹理信息丰富的自然图像稀疏化效果不理想,在基于小波变换的图像压缩中还需改进.为了实现更有效的图像的稀疏表示,文中提出一种新型的基于图像纹理的自适应提升小波变换:根据局部特征将图像自适应分块,预先判断局部图像纹理方向,保持正交性质不变;沿纹理方向应用小波滤波,结合提升变换格式实现即位运算;沿纹理方向插值获取分数像素值,保护纹理信息不被破坏,总体变换对图像纹理描述更有效;结合JPEG2000中的编码方法EBCOT,对变换系数和方向信息分别编码,应用于图像压缩.仿真实验是在数值结果和视觉效果上将文中方法和JPEG2000方法作比较,以体现文中方法的优越性.  相似文献   

4.
基于提升小波变换与自适应PCNN的医学图像融合方法   总被引:4,自引:0,他引:4  
为了更好地满足临床辅助诊断和治疗的需要,提出一种基于提升小波变换的CT与MRI图像的融合方法.该方法在低频子带采用基于区域能量的融合规则;高频子带采用自适应脉冲耦合神经网络(PCNN)的融合规则,通过应用PCNN简化模型把图像逐像素的梯度能量作为PCNN的链接强度,使得PCNN能根据像素梯度能量的变化来自适应地调整链接强度的大小,并根据点火次数确定高频子带融合系数.实验结果表明,文中方法与传统融合方法相比性能优越,丰富了融合图像的边缘及细节信息,可取得更好的融合效果.  相似文献   

5.
针对于遥感图像纹理复杂的特点,提出了一种利用自适应方向提升方案的遥感图像压缩编码新方法。传统的提升方法主要在垂直和水平方向上进行,从而降低垂直和水平方向上像素的相关性;与传统的提升方法不同,基于自适应方向提升的方法充分利用了图像其他纹理方向的相关性来进一步提高预测的精度,从而降低高频部分的能量值。该算法首先利用自适应方向提升的方法对遥感图像进行多尺度快速整数小波变换,然后采用子带位平面编码算法来实现遥感图像的高效压缩编码。实验结果表明,对一般遥感图像,该算法在高倍率压缩的情况下要优于目前的JPEG2000算法。  相似文献   

6.
经典二维小波变换仅在图像的水平和垂直方向进行变换,对图像的纹理信息表示能力不足,基于小波变换的图像增强的效果还不尽人意。为了更好地表示图像的纹理信息,提出一种基于纹理的自适应提升小波的图像增强方法,根据图像的局部特征预测图像的纹理方向,沿纹理方向应用小波变换,使图像的纹理信息表示更准确,而且小波变换法在抑制噪声方面性能优良,将其应用于图像增强,仿真及实验结果表明该方法具有有效性和实用性。  相似文献   

7.
吕倩  倪林  刘权 《计算机工程》2011,37(24):216-218
研究先更新再预测的经典自适应提升小波算法,提出一种基于自回归(AR)模型的二维自适应提升小波变换算法。根据图像局部特性选择自适应更新算子,利用更新后的系数位置关系给出基于AR模型的预测算子,使预测误差功率最小。实验结果表明,与使用最小均方误差标准的自适应预测算法相比,该算法能够降低高频系数能量,且峰值信噪比也有所提高。  相似文献   

8.
Curvelet变换克服了小波变换在处理高维信号时的不足,比小波变换具有更好的方向性、较高的逼近精度和更好的稀疏表达性能。因此将Curvelet变换应用于图像融合领域,能更好地提取图像边缘特征,为融合提取更多的特征信息。利用对偶树复小波-Curvelett变换的多尺度和多方向性特征以及自适应融合规则在选取融合系数上的优势,提出了一种基于对偶树复小波-Curvelet变换的自适应遥感图像融合新算法。算法是将全色图像和多光谱图像进行对偶树复小波-Curvelet变换分解后,针对不同的频率域特点选择不同的融合规则,对低频系数选取区域能量的加权系数自适应融合规则,对高频系数特性选用了区域特征自适应的融合规则,最后通过重构得到融合图像。将其他的融合算法和所提算法进行主观和客观的对比,结果表明,基于对偶树复小波-Curvelet变换区域特征自适应的图像融合算法是一种有效可行的图像融合算法。  相似文献   

9.
基于对象的三维医学图像形状自适应编码算法   总被引:1,自引:0,他引:1  
吴家骥  焦李成  石光明  王磊 《软件学报》2008,19(7):1635-1643
提出了一种针对三维医学图像已知诊断对象区域的形状自适应小波编码方法.该算法仅对对象区域内的像素应用形状自适应小波变换去相关,变换后,对象在变换域中的系数个数与图像域的像素保持相同.为了实现快速无损变换,提出一种基于提升的形状自适应小波变换方法.通过分析形状自适应变换后无效系数的位置,又提出一种改进的OB-3DSPECK(object-based set partitioned embedded block coder)算法,取消了对象区域外无效块或系数的符号输出,即只输出两种符号码流到自适应算术编码器.对于三维医学图像的对象区域,该算法能够提供有损到无损的渐进编解码.实验结果表明,该算法平均SNR比OB-3DSPECK提高0.5dB.此外,由于减少了一种符号输出,使得算术编码过程可选.  相似文献   

10.
提出一种基于GHM多小波变换域上的模糊自适应水印算法。利用多小波系数块的能量、重要系数对小波块进行分类,结合图像自身的局部特性,在多小波系数中的两个相关的细节子图像中自适应地嵌入一幅二值水印图像;为了增强水印的鲁棒性,采用冗余嵌入方法;水印的提取不需要原始图像。实验结果证明,该算法对剪切、JPEG压缩、锐化等多种图像处理具有很好的鲁棒性。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
《计算机科学》2007,34(4):148-148
Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.  相似文献   

18.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

19.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

20.
正The 34th Chinese Control Conference and SICE Annual Conference 2015(CCCSICE2015)is organized by the Technical Committee on Control Theory(TCCT)of Chinese Association of Automation(CAA)and the Society of Instrument and Control Engineers(SICE)of Japan,and locally organized by Hangzhou Dianzi University(HDU).  相似文献   

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