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Lifting Scheme及其在小波图象编码中的应用 被引量:2
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作者 曾剑芬 马争鸣 《中国图象图形学报(A辑)》 CSCD 北大核心 2001年第11期1111-1117,共7页
L ifting Schem e是构造第二代小波的关键技术 .相对于第一代小波而言 ,L ifting Scheme是一种比 Mallat算法更快、更简单和更容易操作的算法 ,也是 JPEG2 0 0 0推荐的算法 .为了将其应用到小波图象编码中 ,提出了一种对 L ifting Schem... L ifting Schem e是构造第二代小波的关键技术 .相对于第一代小波而言 ,L ifting Scheme是一种比 Mallat算法更快、更简单和更容易操作的算法 ,也是 JPEG2 0 0 0推荐的算法 .为了将其应用到小波图象编码中 ,提出了一种对 L ifting Scheme作适当改进以用于小波图象编码的方法 .该方法就是先用 L ifting Scheme来实现 D9/ 7双正交小波变换 ,然后再用这种技术实现的 D9/ 7双正交小波变换来进行图象压缩编码 .在将 L ifting Schem e算法用于小波图象编码的过程中 ,对该算法做了必要的简化 ,以便保证每个提升 (lifting)环节都是 FIR滤波 .同时 ,根据能量守恒的原则 ,重新调整了尺度因子 .实验结果表明 ,这种经过改进的 L ifting Schem e取得了比 展开更多
关键词 小波图象编码 MALLAT算法 liftING scheme 小波分析 图象压缩
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Lifting Scheme的Haar小波在医学图像压缩中的应用研究
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作者 杨强 王华军 罗学刚 《苏州科技学院学报(工程技术版)》 CAS 2013年第2期72-75,共4页
针对医学图像进行实时传输和大量存储时需要进行压缩处理的需求,论述了Lifting Scheme的Haar小波在医学图像压缩中的应用方法。首先,分析了Haar小波的变换原理,然后阐述了基于提升Haar小波的医学图像压缩算法。实验表明,在压缩比和峰值... 针对医学图像进行实时传输和大量存储时需要进行压缩处理的需求,论述了Lifting Scheme的Haar小波在医学图像压缩中的应用方法。首先,分析了Haar小波的变换原理,然后阐述了基于提升Haar小波的医学图像压缩算法。实验表明,在压缩比和峰值信噪比等评价参数方面,基于Lifting Scheme的Haar小波算法在医学图像压缩中取得了较好效果。 展开更多
关键词 提升格式 HAAR小波 医学图像压缩
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基于Lifting Scheme的自适应小波滤波器组的研究
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作者 刘彦杰 张田文 张学良 《哈尔滨商业大学学报(自然科学版)》 CAS 2005年第5期615-619,共5页
具有高阶消失矩的滤波器在分析平稳信号时,要比使用低阶消失矩的滤波器效果好;而在信 号的边缘区和突变区,用低阶消失矩的滤波器会达到更好的效果,所以在这一理论基础的指导下,提 出了一种有效的双正交两通道小波滤波器组的构造方法,它... 具有高阶消失矩的滤波器在分析平稳信号时,要比使用低阶消失矩的滤波器效果好;而在信 号的边缘区和突变区,用低阶消失矩的滤波器会达到更好的效果,所以在这一理论基础的指导下,提 出了一种有效的双正交两通道小波滤波器组的构造方法,它是基于Lifting Scheme的一种自适应结构. 它的突出优点是可以保证信号的完全重建.实验证明,这种自适应的小波滤波器组在很多应用中显然 要优于有固定消失矩的小波滤波器组. 展开更多
关键词 自适应 liftING scheme 小波滤波器 完全重建
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Digital Filter Algorithm Based on Morphological Lifting Scheme and Median Filter 被引量:2
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作者 Lan Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第5期1007-1011,共5页
Abstract--When the circuits in which electronic products are fitted are disturbed by various interrupting signals, wave distortions occur to the normal voltage signals of these circuits. These wave distortions influen... Abstract--When the circuits in which electronic products are fitted are disturbed by various interrupting signals, wave distortions occur to the normal voltage signals of these circuits. These wave distortions influence the normal operation and life cycle of electronic products. To eliminate the harmful effects of interrupting signals on electronic products, in this paper, a digital filter algorithm based on morphological lifting scheme and median filter (MLS-MF), which will be used to filter various interrupting signals existing in the circuits in which electronic products are fitted, is proposed. A variety of interrupting sig- nals have been included in simulation studies, and simulation results have demonstrated the effectiveness and feasibility of the proposed digital filter algorithm in high frequency continuous interference, random background noise and damped oscillatory transient interference filter. Index Terms--Digital filter, lifting scheme, median filter, mor- phology. 展开更多
关键词 Digital filter lifting scheme median filter MORPHOLOGY
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Second-generation wavelet finite element based on the lifting scheme for GPR simulation 被引量:1
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作者 Feng De-Shan Zhang Hua Wang Xun 《Applied Geophysics》 SCIE CSCD 2020年第1期143-153,170,共12页
Ground-penetrating radar(GPR)is a highly efficient,fast and non-destructive exploration method for shallow surfaces.High-precision numerical simulation method is employed to improve the interpretation precision of det... Ground-penetrating radar(GPR)is a highly efficient,fast and non-destructive exploration method for shallow surfaces.High-precision numerical simulation method is employed to improve the interpretation precision of detection.Second-generation wavelet finite element is introduced into the forward modeling of the GPR.As the finite element basis function,the second-generation wavelet scaling function constructed by the scheme is characterized as having multiple scales and resolutions.The function can change the analytical scale arbitrarily according to actual needs.We can adopt a small analysis scale at a large gradient to improve the precision of analysis while adopting a large analytical scale at a small gradient to improve the efficiency of analysis.This approach is beneficial to capture the local mutation characteristics of the solution and improve the resolution without changing mesh subdivision to realize the efficient solution of the forward GPR problem.The algorithm is applied to the numerical simulation of line current radiation source and tunnel non-dense lining model with analytical solutions.Result show that the solution results of the secondgeneration wavelet finite element are in agreement with the analytical solutions and the conventional finite element solutions,thereby verifying the accuracy of the second-generation wavelet finite element algorithm.Furthermore,the second-generation wavelet finite element algorithm can change the analysis scale arbitrarily according to the actual problem without subdividing grids again.The adaptive algorithm is superior to traditional scheme in grid refinement and basis function order increase,which makes this algorithm suitable for solving complex GPR forward-modeling problems with large gradient and singularity. 展开更多
关键词 Ground penetrating radar wave equation second-generation wavelet finite element method lifting scheme forward modeling
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The Lifting Scheme Based on the Second Generation Wavelets 被引量:1
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作者 FENG Hui GUO Lanying XIAO Jinsheng 《Wuhan University Journal of Natural Sciences》 CAS 2006年第3期503-506,共4页
The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing t... The lifting scheme is a custom design construclion of Biorthogonal wavelets, a fast and efficient method to realize wavelet transform,which provides a wider range of application and efficiently reduces the computing time with its particular frame. This paper aims at introducing the second generation wavelets, begins with traditional Mallat algorithms, illustrates the lifting scheme and brings out the detail steps in the construction of Biorthogonal wavelets. Because of isolating the degrees of freedom remaining the biorthogonality relations, we can fully control over the lifting operators to design the wavelet for a particular application, such as increasing the number of the vanishing moments. 展开更多
关键词 lifting scheme the second generation wavelets vanishing moments
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An Improved Algorithm for Image Edge Detection Based on Lifting Scheme 被引量:8
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作者 张红英 吴斌 彭启琮 《Journal of Electronic Science and Technology of China》 2005年第2期113-115,133,共4页
Wavelet transform is an ideal way for edge detection because of its multi-scale property, localization both in time and frequency domain, sensitivity to the abrupt change of signals, and so on. An improved algorithm f... Wavelet transform is an ideal way for edge detection because of its multi-scale property, localization both in time and frequency domain, sensitivity to the abrupt change of signals, and so on. An improved algorithm for image edge detection based on Lifting Scheme is proposed in this paper. The simulation results show that our improved method can better reflect edge information of images. 展开更多
关键词 lifting scheme edge detection image processing second generation wavelet
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Lifting Scheme Based SPIHT Still Image Coding
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作者 沈利军 赵保军 何佩琨 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期70-74,共5页
In order to eliminate float-point operations for fast wavelet transform, an integer D9/7 biorthogonal reversible wavelet transform was accomplished by lifting scheme. The lifting scheme based wavelet transform can be ... In order to eliminate float-point operations for fast wavelet transform, an integer D9/7 biorthogonal reversible wavelet transform was accomplished by lifting scheme. The lifting scheme based wavelet transform can be finished by addition and shift simply. It improved the quality of reconstructive image and greatly reduced the computational complexity due to integer operation. It is suitable for real-time image coding on hardware such as DSP. The simulation results show that the lifting scheme based SPIHT is prior to traditional wavelet based SPHIT in quality and complexity. 展开更多
关键词 SPIHT lifting scheme WAVELET image coding
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Lifting Scheme and Its Application to Edge Detection
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作者 Yang Yan +2 位作者 Qin Qian-qing 《Wuhan University Journal of Natural Sciences》 CAS 2003年第01A期74-76,共3页
Lifting scheme is a useful and very general technique for constructing wavelet decomposition. The paper adapts the lifting into redundant lifting to obtain shift invariant wavelet transform. ... Lifting scheme is a useful and very general technique for constructing wavelet decomposition. The paper adapts the lifting into redundant lifting to obtain shift invariant wavelet transform. In prediction and update stages of the lifting morphological operator is adopted for preserving local maxima of a signal over several scales, which is particularly useful in wavelet\|based signal detec tion. The new transform presented in the paper is applied in multiresoluti on edge detection of medical image and experim ent results are given to show better performance and applicable potentiali ty. 展开更多
关键词 lifting scheme redundant wavelet transform morpholog ical operator edge detection
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An Image Fusion Algorithm Based on Lifting Scheme
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作者 BAI Di FAN Qibin SHU Qian 《Geo-Spatial Information Science》 2005年第3期171-175,200,共6页
Taking the advantage of the lifting scheme's characters that can build wavelet translorms tor transforming from integer to integer and the quality of the reconstructing image'is independent of the topology way adopt... Taking the advantage of the lifting scheme's characters that can build wavelet translorms tor transforming from integer to integer and the quality of the reconstructing image'is independent of the topology way adopted by the boundary, an image fusion algorithm based on lifting scheme is proposed. This paper discusses the fundamental theory of lifting scheme firstly and then after taking transform analysis according to a kind of images that need to be confused. 展开更多
关键词 lifting schemes image processing integer wavelet transform image fusion
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A NEW TWO-DIMENSIONAL SIGNAL DECOMPOSITION SCHEME USING THE EXTREME-LIFTING SCHEME
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作者 Liu Baofang Ping Xijian Deng Guanglin Shao Meizhen(Dept. of Info. Sci., University of Information Engineering, Zhengzhou 450002)(P.O.Box 1965, Beijing 100091) 《Journal of Electronics(China)》 2001年第2期105-112,共8页
This paper discusses the signal decomposition method using the extreme-lifting scheme and two two-dimensional decomposition schemes: separable one-dimensional scheme and two-dimensional scheme with quincunx sampling. ... This paper discusses the signal decomposition method using the extreme-lifting scheme and two two-dimensional decomposition schemes: separable one-dimensional scheme and two-dimensional scheme with quincunx sampling. The structure of the relation "~" between Ex and Ey of these two schemes is symmetrical and both these two schemes have shortcomings)An unsymmetrical scheme of the extreme-lifting scheme is proposed in this paper, which canbe directly used to decompose two-dimensional image and can get better decomposition result than the two schemes with little computation cost. 展开更多
关键词 SIGNAL DECOMPOSITION Min-lifting scheme Quincunx sampling liftING scheme
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A COMPRESSION ALGORITHM FOR ECG BASED ON INTEGER LIFTING SCHEME WAVELET TRANSFORM
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作者 Zhang Kunyan Guo Yinjing Lü Wenhong Sun Jinping Wang Xiuzhen 《Journal of Electronics(China)》 2007年第5期674-678,共5页
In view of the shortcomes of conventional ElectroCardioGram (ECG) compression algo- rithms,such as high complexity of operation and distortion of reconstructed signal,a new ECG compression encoding algorithm based on ... In view of the shortcomes of conventional ElectroCardioGram (ECG) compression algo- rithms,such as high complexity of operation and distortion of reconstructed signal,a new ECG compression encoding algorithm based on Set Partitioning In Hierarchical Trees (SPIHT) is brought out after studying the integer lifting scheme wavelet transform in detail.The proposed algorithm modifies zero-tree structure of SPIHT,establishes single dimensional wavelet coefficient tree of ECG signals and enhances the efficiency of SPIHT-encoding by distributing bits rationally,improving zero-tree set and ameliorating classifying method.For this improved algorithm,floating-point com- putation and storage are left out of consideration and it is easy to be implemented by hardware and software.Experimental results prove that the new algorithm has admirable features of low complexity, high speed and good performance in signal reconstruction.High compression ratio is obtained with high signal fidelity as well. 展开更多
关键词 Electro Cardio Gram (ECG) Integer lifting scheme Wavelet transform Set Partitioning InHierarchical Trees (SPIHT)
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Feature extraction of gear-localized defect using adaptive lifting scheme and local gradient maps
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作者 Zhang Lu Zhao Hong +3 位作者 Li Zhen Qi Keyu Li Zongyao Yao Nianling 《Engineering Sciences》 EI 2013年第1期78-82,88,共6页
In this paper,the adaptive lifting scheme (ALS) and local gradient maps (LGM) are proposed to isolate the transient feature components from the gearbox vibration signals. Based on entropy minimization rule,the ALS is ... In this paper,the adaptive lifting scheme (ALS) and local gradient maps (LGM) are proposed to isolate the transient feature components from the gearbox vibration signals. Based on entropy minimization rule,the ALS is employed to change properties of an initial wavelet and design adaptive wavelet. Then LGM is applied to characterize the transient feature components in detail signal of decomposition results using ALS. In the present studies, the orthogonal Daubechies 4 (Db 4) wavelet is used as the initial wavelet. The proposed method is applied to both simulated signals and vibration signals acquired from a gearbox for periodic impulses detection. The two conventional methods (cepstrum analysis and Hilbert envelope analysis) and the orthogonal Db4 wavelet are also used to analyze the same signals for comparison. The results demonstrate that the proposed method is more effective in extracting transient components from noisy signals. 展开更多
关键词 adaptive lifting scheme local gradient maps GEARBOX fault detection
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Characterization of the Modified Lifting Scheme Compression Method of EMG Signals
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作者 Ele Pierre Ntsama Eloundou Pascal Tonye Emmanuel 《通讯和计算机(中英文版)》 2011年第11期1013-1021,共9页
关键词 肌电信号 提升方案 压缩方法 表征方法 改性 小波包变换 信号噪声比 数据压缩
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一种生成双正交紧支复小波的Lifting方法 被引量:18
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作者 陈祥训 淡文刚 《中国电机工程学报》 EI CSCD 北大核心 2001年第5期34-37,42,共5页
提出了一种构造双正交紧支复小波的方法 :以现有任何一种正交或双正交实小波为基础 ,可构造出消失矩阶数可任意选定的无穷多个相频特性 (包括线性相位特性 )不同的双正交紧支复小波。其特点为 :由于是双正交紧支型 ,可采用Mallat算法等... 提出了一种构造双正交紧支复小波的方法 :以现有任何一种正交或双正交实小波为基础 ,可构造出消失矩阶数可任意选定的无穷多个相频特性 (包括线性相位特性 )不同的双正交紧支复小波。其特点为 :由于是双正交紧支型 ,可采用Mallat算法等快速算法 ,因此使用时实时性好 ;因为是复小波 ,所以能提取电力系统至关重要的相位信息 ;具有多种相频特性 ,便于与相频特性多变的电力系统信号匹配等 ,因此这类小波在电力系统有广泛的应用前景。 展开更多
关键词 电力系统 小波分析 lifting方法 双正交紧支复小波
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用lifting方法构造具有线性相位的双正交小波 被引量:3
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作者 陈佩 张卫东 +1 位作者 许晓鸣 徐润生 《电子与信息学报》 EI CSCD 北大核心 2002年第4期486-491,共6页
Lifting作为第2代小波的构造方法,同样能够构造出第1代小波。与传统的Daubechies方法相比,该方法简单易懂,并且容易用格状结构(Lattice structrue)构造出满足特定要求的小波。该文首先根据Lawton矩阵的性质证明了几乎所有由此方法构造... Lifting作为第2代小波的构造方法,同样能够构造出第1代小波。与传统的Daubechies方法相比,该方法简单易懂,并且容易用格状结构(Lattice structrue)构造出满足特定要求的小波。该文首先根据Lawton矩阵的性质证明了几乎所有由此方法构造出的小波满足双正交条件,然后考虑如何构造具有线性相位性质的双正交小波,最后列举几个例子说明lifting方法。 展开更多
关键词 Lfiting方法 双正交小波 Lawton矩阵 完全重构 线性相位
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细分曲面切片轮廓线的Lifting小波变换 被引量:1
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作者 区士颀 宾鸿赞 《中国机械工程》 EI CAS CSCD 北大核心 2005年第17期1519-1523,共5页
基于Lifting小波变换原理对细分曲面实体切片操作产生的离散交点序列进行处理,将它们组织为属于多个层次结构的多分辨率曲线。用4种不同的Lifting小波变换进行了多分辨率曲线的构造实验,并对产生的多分辨率曲线进行了对比,讨论分析了这... 基于Lifting小波变换原理对细分曲面实体切片操作产生的离散交点序列进行处理,将它们组织为属于多个层次结构的多分辨率曲线。用4种不同的Lifting小波变换进行了多分辨率曲线的构造实验,并对产生的多分辨率曲线进行了对比,讨论分析了这些Lifting变换方法的性能特点。 展开更多
关键词 快速原型制造技术 细分曲面 切片 lifting小波变换
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利用lifting方法设计双正交滤波器组 被引量:1
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作者 徐小平 王峰 《纺织高校基础科学学报》 CAS 2006年第2期182-185,共4页
研究了用lifting方法设计三通道自适应提升双正交滤波器组.在设计中,用子带编码增益作为设计准则,从任意一个滤波器组(标准正交或双正交)开始,通过联合自适应提升方法来设计三通道双正交滤波器组.最后,给出例子说明子带码增益明显提高.
关键词 lifting方法 双正交滤波器组 子带编码增益
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用lifting方法设计最优LPPR-FIR滤波器组
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作者 陈佩 张卫东 +1 位作者 许晓鸣 徐润生 《电子与信息学报》 EI CSCD 北大核心 2002年第9期1202-1208,共7页
该文研究了如何用lifting方法构造线性相位完全重建有限脉冲响应(LPPR-FIR)滤波器组的优化设计问题,即如何转化为一个二次型优化问题.然后把该方法推广到M带FIR滤波器组,考虑在一种特殊情形中如何构造具有线性相位性质的M带PR-FIR滤波器... 该文研究了如何用lifting方法构造线性相位完全重建有限脉冲响应(LPPR-FIR)滤波器组的优化设计问题,即如何转化为一个二次型优化问题.然后把该方法推广到M带FIR滤波器组,考虑在一种特殊情形中如何构造具有线性相位性质的M带PR-FIR滤波器组,最后列举了几个例子说明如何用lifting方法构造M带LPPR-FIR滤波器组。 展开更多
关键词 LPPR-FIR滤波器组 lifting方法 M带滤波器组 完全重构 线性相位
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Fault Diagnosis of a Rotor Based on a Lifting Wavelet and Local Wave 被引量:1
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作者 WANG Feng-li GAO Hong-tao ZHAO De-you 《International Journal of Plant Engineering and Management》 2010年第1期13-17,共5页
Aiming at the mode mixture in local wave decomposition(LWD) caused by a noise signal, the original data is preprocessed using the lifting wavelet transformation to suppress abnormal interference of noise and improve... Aiming at the mode mixture in local wave decomposition(LWD) caused by a noise signal, the original data is preprocessed using the lifting wavelet transformation to suppress abnormal interference of noise and improve the quality of decomposition. It is employed to analyze the vibration signal of rotor rub-impact for extracting the weak impulsive feature. The signal is decomposed into intrinsic mode functions by LWD, then the high-frequency components are analyzed by Hilbert envelop demodulation. The period of the impulse response can be achieved, and the modulate fault feature of the vibration signal of a rotor system with rub-impact fault can be extracted exactly. Analysis results show that the proposed method is accurate and efficient, and is expected to be applied in engineering practice effectively. 展开更多
关键词 local wave lifting scheme fault diagnosis envelope demodulation RUB-IMPACT
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