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1.
分形图偈压缩及实现方法   总被引:1,自引:0,他引:1  
自然界非常复杂的图像只能借助于分形几何学来处理,分形图像压缩就是利用分形几何学的有关原理进行编码以实现图像压缩。  相似文献   

2.
分形图像编码的原理及其发展趋势   总被引:8,自引:0,他引:8  
介绍了分形图像编码的原理及分形图像压缩的编码方法,提出了分形图像压缩编码的改进方法及其发展趋势。  相似文献   

3.
基于区域分割的分形图像压缩编码方法   总被引:7,自引:0,他引:7  
在基于块分割的分形图像压缩编码研究基础上,提出了一种基于区域分割和十字搜索模型的分形图像压缩编码新方法,实验结果表明,该方法与基于块分割的分形图像压缩编码方法相比,在保持恢复图像质量的前提下,压缩比和编码速度都有了显著的提高,是一种有效的分形图像压缩编码方法。  相似文献   

4.
分形图像压缩编码是当今图像编码领域研究的热点之一,是一种具有独特优势且极有发展前途的数据压缩技术。本文从分形基本理论出发,对分形图像压缩编码思想、编码方法等进行了综述,并介绍了分形图像压缩编码的一些改进方法。最后,探讨了分形图像压缩编码的发展方向。  相似文献   

5.
卢洵  李世铮 《电视技术》1999,(12):13-14
阐述了分形图像压缩的理论基础,了分形在视频图像空中的应用。分形图像压缩编码方法能够实现很高的压缩比,具有很高的实用价值。  相似文献   

6.
介绍分形学的产生意义和作用,提出分形物体的数学模型,讨论分形技术应用于图像压缩编码中的迭代收缩变换算法。  相似文献   

7.
针对目前存在图像压缩率不高、全局搜索或遗传算法寻找最优分形图像压缩编码速度慢的不足,将基因表达式编程应用于分形图像压缩编码,提高求解分形图像压缩编码速度和压缩比.首先从理论上对二值图像压缩编码的求解过程和基因表达式编程在压缩编码中的作用机理进行分析;然后,研究分形图像压缩编码的基因和染色体的表示方法,适应度函数设计以及选择、变异、插串、基因变换、基因重组等基因遗传进化操作过程.提出基因表达式编程的分形图像压缩算法,求解分形图像压缩编码的最优解.实验结果表明,基因表达式编程应用于分形图像压缩编码,具有较强的全局寻优能力,搜索最优解的速度比遗传算法快约2倍,图像压缩率高.  相似文献   

8.
小波分形混合图像压缩编码进展   总被引:2,自引:0,他引:2  
介绍了分形、小波图像压缩编码进展情况,简要讨论了小波分形混合图像压缩的一般方法,并对国内外小波分形图像压缩的现状进行了详细的说明,探讨了静止图像压缩编码的发展方向。  相似文献   

9.
引入非线性变换的分形图像压缩编码   总被引:2,自引:0,他引:2  
提出了一种基于非线性变换的分形图像压缩编码方法。证明了引入的非线性变换满足压缩迭代映射理论。模拟实验的结果表明 ,与传统的分形图像压缩编码方法相比 ,压缩比和峰值信噪比均有所改善。  相似文献   

10.
吕超  曹靖城  周帅 《信息技术》2023,(1):137-142
针对传统编码模型存在的图像分割处理效果不佳、分割精度不高、耗时较长以及编码质量较差的问题,提出基于深度学习的分形图像压缩编码模型。建立图像分割约束条件,对图像进行分割处理,以处理后的图像作为深度学习中ResNet网络模型的输入,提取原始分形图像的特征并将图像块分类;建立特征图像块匹配规则,排序图像块,记录分形码,将分形码作为图像在度量空间内的表现形式,通过度量空间的压缩变换实现分形图像压缩编码。实验结果表明:所提模型的图像压缩编码质量较高,具有一定的应用价值。  相似文献   

11.
This paper relates for the first time, multiple resonant frequencies of fractal element antennas using Koch curves to their fractal dimension. Dipole and monopole antennas based fractal Koch curves studied so far have generally been limited to certain standard configurations of the geometry. It is possible to generalize the geometry by changing its indentation angle, to vary its fractal similarity dimension. This variation results in self-similar geometry which can be generated by a recursive algorithm. Such a variation is found to have a direct influence on the input characteristics of dipole antennas. The primary resonant frequency, the input resistance at this resonance, and the ratio of first two resonant frequencies, have all been directly related to the fractal dimension. Curve-fit expressions can also be obtained for the performance of antennas at their primary resonance, in terms of fractal iteration and fractal dimension. The antenna characteristics have been studied using extensive numerical simulations and are experimentally verified. These findings underscore the significance of fractal dimension as an important mathematical property of fractals that can be used as a design parameter for antennas. The use of these ideas would not only reduce the computational intensity of optimization approaches for design of fractal shaped antennas, but also help antenna designers approach the problem systematically. Design formulation for antennas based on other fractal geometries can be similarly obtained after identifying suitable parameters of variation. This would therefore help analytical design of multiband and multifunctional antennas using fractal geometries.  相似文献   

12.
This article proposes a novel design based on fractal geometries to miniaturize the antenna. The proposed geometry is inspired from a combination of two fractal geometries, Giuseppe Peano and Minkowski fractal geometry. The dielectric material used is Roggers TMM4 lossy, with a dielectric constant of εr = 4.5 the proposed geometry shows miniaturization by shifting the lowest resonant frequency towards the lower frequency side. The geometry is made by addition of the scaled version of base geometry at the vertices and reducing the total dimension so as to maintain the outer dimensions constant. The maximum achieved miniaturization in terms of % is 37.25%. The detailed study for different scaling ratios and different iterations has been performed and mentioned in the paper.  相似文献   

13.
分形几何方法是一种新的图像压缩编码方法。本文介绍了分形几何和分形图像压缩的一些基本概念,以及以分形为基础的几种图像压缩编码方法。  相似文献   

14.
The growth kinetics of lithium clusters in germanium is studied. Ham’s theory is generalized to describe the growth of fractal clusters. It is shown that the lithium clusters in germanium are characterized by a fractal geometry with a fractal dimension of 2.4.  相似文献   

15.
将分形几何应用于天线设计可以产生具有多频段或小型化特征的分形天线。传统的多频段分形天线Sierpinski垫片天线由于是有限次迭代生成的,它存在截取效应低端谐振频率比值几乎是其几何相似性因子的两倍,从而限制了其实际应用。本文针对一种小型化的加载型Sierpinski垫片天线进行了有效的研究,证实了加载对降低天线高端谐振频率的有效性,同时分析了结构参数对其工作频段的影响并提出了增大天线张角的方式以进一步小型化天线。  相似文献   

16.
17.
The objective of this research is to model the mammographic parenchymal and ductal patterns and enhance the microcalcifications using a deterministic fractal approach. According to the theory of deterministic fractal geometry, images can be modeled by deterministic fractal objects which are attractors of sets of two-dimensional (2-D) affine transformations. The iterated functions systems and the collage theorem are the mathematical foundations of fractal image modeling. Here, a methodology based on fractal image modeling is developed to analyze and model breast background structures. The authors show that general mammographic parenchymal and ductal patterns can be well modeled by a set of parameters of affine transformations. Therefore, microcalcifications can be enhanced by taking the difference between the original image and the modeled image. The authors' results are compared with those of the partial wavelet reconstruction and morphological operation approaches. The results demonstrate that the fractal modeling method is an effective way to enhance microcalcifications. It may also be able to improve the detection and classification of microcalcifications in a computer-aided diagnosis system.  相似文献   

18.
分形在天线雷达散射截面减缩中的应用   总被引:3,自引:1,他引:2       下载免费PDF全文
首次提出利用分形独特的填充性能实现天线雷达散射截面(RCS)减缩,同时,分形单元可以减缩单元间的耦合,提高阵列的性能。给出了分形天线与常规天线辐射、散射特性的对比,表明将分形的概念用于天线设计中,不仅可以减小互耦,提高天线阵列的辐射性能,而且也可以减小天线的雷达散射截面,对天线的隐身有一定的借鉴作用。  相似文献   

19.
《Electronics letters》2001,37(19):1150-1151
Fractal antenna engineering concepts have been successfully combined with genetic algorithms to develop a powerful design optimisation tool. The genetic optimisation approach developed can simultaneously optimise the geometry of a fractal antenna, locations of loads, component values of loads, and projected length of the fractal antenna. The results suggest that a 30 to 55% size reduction can be achieved by optimising the fractalisation of a given antenna. The knowledge gained from this study is directly applicable to the design of miniature multiband fractal antennas  相似文献   

20.
基于分形理论的太赫兹光谱识别   总被引:1,自引:0,他引:1  
介绍了分形的基本概念和分形盒维算法.提出了一种新的太赫兹光谱识别方法.实验中测得了两种中药的太赫兹光谱,算出了它们的盒维数并进行了比较.通过这种方法使不同的药品得到了很好的鉴别.  相似文献   

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