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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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A NEW ADAPTIVE FILTERING SCHEME BASED ON WAVELET TRANSFORM
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作者 Wang Yongde He Peiyu Wang Chunxia(Dept. of Radio Electronics, Sichuan University, Chengdu 610064) 《Journal of Electronics(China)》 1999年第3期257-262,共6页
Based on the scale function representation for a function in L2(R), a new wavelet transform based adaptive system identification scheme is proposed. It can reduce the amount of computation by exploiting the decimation... Based on the scale function representation for a function in L2(R), a new wavelet transform based adaptive system identification scheme is proposed. It can reduce the amount of computation by exploiting the decimation properties and keep the advantage of quasi-orthogonal transform of the discrete wavelet, transform (DWT). The issue has been supported by computer simulations. 展开更多
关键词 IIR SP NLMS A NEW ADAPTIVE FILTERING scheme based on wavelet transform DWT IEEE
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Seismic data compression based on integer wavelet transform 被引量:1
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作者 WANG Xi-zhen(王喜珍) TENG Yun-tian(滕云田) +1 位作者 GAO Meng-tan(高孟潭) JIANG Hui(姜慧) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第z1期123-128,共6页
Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied.... Due to the particularity of the seismic data, they must be treated by lossless compression algorithm in some cases. In the paper, based on the integer wavelet transform, the lossless compression algorithm is studied. Comparing with the traditional algorithm, it can better improve the compression rate. CDF (2, n) biorthogonal wavelet family can lead to better compression ratio than other CDF family, SWE and CRF, which is owe to its capability in can- celing data redundancies and focusing data characteristics. CDF (2, n) family is suitable as the wavelet function of the lossless compression seismic data. 展开更多
关键词 lossless compression integer wavelet transform lifting scheme biorthogonal wavelet
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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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AN EFFICIENT 3-DIMENSIONAL DISCRETE WAVELET TRANSFORM ARCHITECTURE FOR VIDEO PROCESSING APPLICATION 被引量:1
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作者 Ganapathi Hegde Pukhraj Vaya 《Journal of Electronics(China)》 2012年第6期534-540,共7页
This paper presents an optimized 3-D Discrete Wavelet Transform (3-DDWT) architecture. 1-DDWT employed for the design of 3-DDWT architecture uses reduced lifting scheme approach. Further the architecture is optimized ... This paper presents an optimized 3-D Discrete Wavelet Transform (3-DDWT) architecture. 1-DDWT employed for the design of 3-DDWT architecture uses reduced lifting scheme approach. Further the architecture is optimized by applying block enabling technique, scaling, and rounding of the filter coefficients. The proposed architecture uses biorthogonal (9/7) wavelet filter. The architecture is modeled using Verilog HDL, simulated using ModelSim, synthesized using Xilinx ISE and finally implemented on Virtex-5 FPGA. The proposed 3-DDWT architecture has slice register utilization of 5%, operating frequency of 396 MHz and a power consumption of 0.45 W. 展开更多
关键词 3-D Discrete wavelet transform (3-DDWT) lifting scheme PIPELINING Video coding Low power
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Low complexity reconfigurable architecture for the 5/3 and 9/7 discrete wavelet transform
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作者 Xiong Cheng yi Tian Jinwen Liu Jian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期303-308,共6页
Efficient reconfigurable VLSI architecture for 1-D 5/3 and 9/7 wavelet transforms adopted in JPEG2000 proposal, based on lifting scheme is proposed. The embedded decimation technique based on fold and time multiplexin... Efficient reconfigurable VLSI architecture for 1-D 5/3 and 9/7 wavelet transforms adopted in JPEG2000 proposal, based on lifting scheme is proposed. The embedded decimation technique based on fold and time multiplexing, as well as embedded boundary data extension technique, is adopted to optimize the design of the architecture. These reduce significantly the required numbers of the multipliers, adders and registers, as well as the amount of accessing external memory, and lead to decrease efficiently the hardware cost and power consumption of the design. The architecture is designed to generate an output per clock cycle, and the detailed component and the approximation of the input signal are available alternately. Experimental simulation and comparison results are presented, which demonstrate that the proposed architecture has lower hardware complexity, thus it is adapted for embedded applications. The presented architecture is simple, regular and scalable, and well suited for VLSI implementation. 展开更多
关键词 VLSI discrete wavelet transform lifting scheme embedded decimation reeonfigurable.
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An Approach to Integer Wavelet Transform for Medical Image Compression in PACS
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作者 YANG Yan ZHANG Dong 《Wuhan University Journal of Natural Sciences》 CAS 2000年第2期204-206,共3页
We study an approach to integer wavelet transform for lossless compression of medical image in medical picture archiving and communication system (PACS). By lifting scheme a reversible integer wavelet transform is gen... We study an approach to integer wavelet transform for lossless compression of medical image in medical picture archiving and communication system (PACS). By lifting scheme a reversible integer wavelet transform is generated, which has the similar features with the corresponding biorthogonal wavelet transform. Experimental results of the method based on integer wavelet transform are given to show better performance and great applicable potentiality in medical image compression. 展开更多
关键词 Key words integer wavelet transform lifting scheme lossless compression PACS
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Lifting Scheme and Its Application to Edge Detection
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作者 Yang Yan He Chu +2 位作者 Liao Ya-i Cao Yang 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.In prediction and update sta... 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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A Parallel-based Lifting Algorithm and VLSI Architecture for DWT
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作者 Xiong Chengyi Tian Jinwen +1 位作者 Liu Jian Gao Zhirong 《Journal of Electronics(China)》 2006年第2期244-248,共5页
A novel Parallel-Based Lifting Algorithm (PBLA) for Discrete Wavelet Transform (DWT), exploiting the parallelism of arithmetic operations in all lifting steps, is proposed in this paper. It leads to reduce the cri... A novel Parallel-Based Lifting Algorithm (PBLA) for Discrete Wavelet Transform (DWT), exploiting the parallelism of arithmetic operations in all lifting steps, is proposed in this paper. It leads to reduce the critical path latency of computation, and to reduce the complexity of hardware implementation as well. The detailed derivation on the proposed algorithm, as well as the resulting Very Large Scale Integration (VLSI) architecture, is introduced, taking the 9/7 DWT as an example but without loss of generality. In comparison with the Conventional Lifting Algorithm Based Implementation (CLABI), the critical path latency of the proposed architecture is reduced by more than half from (4Tm + 8Ta)to Tm + 4Ta, and is competitive to that of Convolution-Based Implementation (CBI), but the new implementation will save significantly in hardware. The experimental results demonstrate that the proposed architecture has good performance in both increasing working frequency and reducing area. 展开更多
关键词 Discrete wavelet transform (DFT) lifting scheme PARALLEL Very Large Scale Integration(VLSI)
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A Novel VLSI Architecture for Real-Time Line-Based Wavelet Transform Using Lifting Scheme
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作者 刘凯 王柯俨 +1 位作者 李云松 吴成柯 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第5期661-672,共12页
In this paper, we propose a VLSI architecture that performs the line-based discrete wavelet transform (DWT) using a lifting scheme. The architecture consists of row processors, column processors, an intermediate buf... In this paper, we propose a VLSI architecture that performs the line-based discrete wavelet transform (DWT) using a lifting scheme. The architecture consists of row processors, column processors, an intermediate buffer and a control module. Row processor and Column processor work as the horizontal and vertical filters respectively. Intermediate buffer is composed of five FIFOs to store temporary results of horizontal filter. Control module schedules the output order to external memory. Compared with existing ones, the presented architecture parallelizes all levels of wavelet transform to compute multilevel DWT within one image transmission time, and uses no external but one intermediate buffer to store several line results of horizontal filtering, which decreases resource required significantly and reduces memory efficiently. This architecture is suitable for various real-time image/video applications. 展开更多
关键词 line-based wavelet transforms lifting-based VLSI
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Speech compression scheme based on wavelet transform and vector quantization
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作者 LI Shuhong SANG Enfang(Dept. of Underwater, Acoustic, Harbin Engineering University Harbin 150001) 《Chinese Journal of Acoustics》 1999年第4期344-352,共9页
A coding method of speech compression, which is based on Wavlet Transform and Vector Quantization (VQ), is developed and studied. The Wavlet Thansform or Wavlet Packet Thansform is used to process the speech signal, t... A coding method of speech compression, which is based on Wavlet Transform and Vector Quantization (VQ), is developed and studied. The Wavlet Thansform or Wavlet Packet Thansform is used to process the speech signal, then VQ is used to compress the coefficients of Wavlet Thansform, and the entropy coding is used to decrease the bit rate. The experimental results show that the speech signal, sampled by 8 kHz sampling rate and 8 bit quatisation,i.e., 64 kbit/s bit rate, can be compressed to 6 - 8 kbit/s, and still have high speech quality,and the low-delay, only 8 ms. 展开更多
关键词 IEEE In Speech compression scheme based on wavelet transform and vector quantization
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An Improved SPIHT Algorithm for Image Compression in Low Bit Rate
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作者 Ping Liu Guanfeng Li 《Communications and Network》 2013年第3期245-248,共4页
Aiming at shortage of the SPIHT algorithm, an improved image compression algorithm is proposed, in order to overcome the shortcomings of decoding image quality and coding time, LS9/7 lifting wavelet transform is adopt... Aiming at shortage of the SPIHT algorithm, an improved image compression algorithm is proposed, in order to overcome the shortcomings of decoding image quality and coding time, LS9/7 lifting wavelet transform is adopted. According to the characteristics of the human visual system (HVS), the scanning mode and the method to determine the threshold of algorithm are changed to improve the quality of reconstruction image. On the question of repeating scan of SPIHT algorithm, using maximum list thought, greatly reduce the computation and save operating time. The experimental results have proved that the improved algorithm of image decoding time and the quality of reconstruction images are better than the original algorithm , especially in the case of low bit rate. 展开更多
关键词 wavelet transformation lifting scheme THRESHOLD Set Partitioning in Hierarchical Trees(SPIHT) Human Visual System(HVS) Image Compression Low BIT Rate
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Lifting scheme of symmetric tight wavelets frames
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作者 ZHUANG BoJin YUAN WeiTao PENG LiZhong 《Science in China(Series F)》 2008年第8期1117-1124,共8页
This paper proposes a method to realize the lifting scheme of tight frame wavelet filters. As for 4-channel tight frame wavelet filter, the tight frame transforms' matrix is 2×4, but the lifting scheme transform... This paper proposes a method to realize the lifting scheme of tight frame wavelet filters. As for 4-channel tight frame wavelet filter, the tight frame transforms' matrix is 2×4, but the lifting scheme transforms' matrix must be 4×4. And in the case of 3-channel tight frame wavelet filter, the transforms' matrix is 2×3, but the lifting scheme transforms' matrix must be 3×3. In order to solve this problem, we introduce two concepts: transferred polyphase matrix for 4-channel filters and transferred unitary matrix for 3-channel filters. The transferred polyphase matrix is symmetric/antisymmetric. Thus, we use this advantage to realize the lifting scheme. 展开更多
关键词 lifting scheme tight frame wavelet transform
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自适应提升小波变换与图象去噪 被引量:12
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作者 王志武 丁国清 +1 位作者 颜国正 林良明 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2002年第6期447-450,共4页
引入了基于提升法的自适应离散小波变换 ,根据LMS自适应法确定伯恩斯坦预测算子的权重系数 ,使其自适应匹配特定的数据序列 ,而且应用该方法结合软域值可实现信号去噪 ,最后扩展该方法应用于二维图象的去噪 ,数值实验表明自适应提升小... 引入了基于提升法的自适应离散小波变换 ,根据LMS自适应法确定伯恩斯坦预测算子的权重系数 ,使其自适应匹配特定的数据序列 ,而且应用该方法结合软域值可实现信号去噪 ,最后扩展该方法应用于二维图象的去噪 ,数值实验表明自适应提升小波变换有效地实现了图象的去噪而且保持了图像的边缘和纹理特性 。 展开更多
关键词 小波变换 提升法 图象去噪 自适应 图像处理 LMS 伯恩斯坦滤波器预测算子
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采用非降采样第二代小波变换的信号降噪方法 被引量:11
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作者 鲍文 周瑞 +2 位作者 李宁 杨建国 于达仁 《中国电机工程学报》 EI CSCD 北大核心 2008年第20期82-87,共6页
信号降噪是机电设备故障诊断领域中的重要研究课题。根据噪声的小波变换系数随着小波分解尺度的增加而迅速趋向于零这一特性,基于小波变换的降噪方法得到了广泛应用。文中研究了非降采样第二代小波变换的构造方法,给出了非降采样第二代... 信号降噪是机电设备故障诊断领域中的重要研究课题。根据噪声的小波变换系数随着小波分解尺度的增加而迅速趋向于零这一特性,基于小波变换的降噪方法得到了广泛应用。文中研究了非降采样第二代小波变换的构造方法,给出了非降采样第二代小波变换中预测算子和更新算子的时域计算公式,分析了算法的计算复杂度,并在此基础上提出采用非降采样第二代小波的信号降噪方法。由于非降采样小波分解后的各层系数和原始信号的长度均相同,因此在具备平移不变性的同时还能保留更多的时域信息,从而可以提高信号的降噪效果。对仿真信号和实际信号进行了试验,结果表明,该方法较理想地对信号进行了降噪处理,并且能够较好地保留原始信号中的故障特征。 展开更多
关键词 非降采样小波变换 提升方案 降噪 故障诊断
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基于提升机制小波变换的SAR与多光谱图像融合算法 被引量:13
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作者 郑永安 陈玉春 +1 位作者 宋建社 赵伟舟 《计算机工程》 EI CAS CSCD 北大核心 2006年第6期195-197,共3页
在对提升机制小波变换的原理和特点研究的基础上,结合SAR图像与多光谱图像不同成像特性,提出了一种基于提升小波变换区域融合的SAR与多光谱图像融合方法。对于小波变换后的高频子图像,选择区域标准差大的作为融合后的子图像;对于低频子... 在对提升机制小波变换的原理和特点研究的基础上,结合SAR图像与多光谱图像不同成像特性,提出了一种基于提升小波变换区域融合的SAR与多光谱图像融合方法。对于小波变换后的高频子图像,选择区域标准差大的作为融合后的子图像;对于低频子图像,定义区域均值的平均相对偏差作为阈值,融合子图像区域均值偏差大于阈值时,采用逻辑滤波方法融合,反之采用基于像素值加权平均的融合规则。实验证明,该算法能够有效融合SAR与多光谱图像之间的互补信息,与其它用于图像融合的小波变换方法相比,运算速度较快,易于DSP实现。 展开更多
关键词 小波变换 提升机制 图像融合
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自适应提升小波变换与信号去噪 被引量:8
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作者 王志武 丁国清 +1 位作者 颜国正 林良明 《计算机工程与应用》 CSCD 北大核心 2002年第2期28-29,162,共3页
文章引入了基于提升法的自适应离散小波变换,根据LMS自适应法使伯恩斯坦预测算子自适应匹配特定的数据序列,而且应用该方法于信号的软域值去噪,数值仿真实验表明自适应提升小波变换同经典的小波变换相比,去噪后信号的信噪比效率相近,提... 文章引入了基于提升法的自适应离散小波变换,根据LMS自适应法使伯恩斯坦预测算子自适应匹配特定的数据序列,而且应用该方法于信号的软域值去噪,数值仿真实验表明自适应提升小波变换同经典的小波变换相比,去噪后信号的信噪比效率相近,提升方法的优点在于其设计上的灵活性和计算简单。 展开更多
关键词 小波变换 提升法 自适应 信号去噪 信号处理
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提升小波变换及其在图像处理中的应用 被引量:11
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作者 高世伟 郭雷 +2 位作者 杜亚琴 杨宁 陈亮 《计算机工程与设计》 CSCD 北大核心 2007年第9期2066-2069,共4页
提升算法是一种新的双正交小波构造方法,此方法大大降低了计算的复杂程度,因此该算法可以有效地减少程序运行时间。详细说明了提升算法的原理及实现步骤,并结合该算法介绍了它在图像处理中的一些应用。实验表明基于提升算法设计的图像... 提升算法是一种新的双正交小波构造方法,此方法大大降低了计算的复杂程度,因此该算法可以有效地减少程序运行时间。详细说明了提升算法的原理及实现步骤,并结合该算法介绍了它在图像处理中的一些应用。实验表明基于提升算法设计的图像处理系统有很好的性能。 展开更多
关键词 小波变换 提升算法 图像去噪 图像压缩 图像融合
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基于二维提升小波的火电厂周期性数据压缩算法 被引量:29
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作者 鲍文 周瑞 刘金福 《中国电机工程学报》 EI CSCD 北大核心 2007年第29期96-101,共6页
针对火电厂生产运行中产生的大量周期性实时数据,提出了一种新的数据压缩与解压缩算法。为了更加有效地降低周期性数据中存在的冗余,该算法首先将待压缩的周期性数据从一维空间转换到二维空间,然后采用基于二维提升格式的对称双正交小... 针对火电厂生产运行中产生的大量周期性实时数据,提出了一种新的数据压缩与解压缩算法。为了更加有效地降低周期性数据中存在的冗余,该算法首先将待压缩的周期性数据从一维空间转换到二维空间,然后采用基于二维提升格式的对称双正交小波滤波器组对数据进行压缩和解压缩。利用实际测取的电力生产过程中的周期性数据对算法进行验证,试验结果表明,在相同的压缩比下,基于二维小波压缩的重构效果优于基于一维小波压缩的重构效果。因此该算法是一种有效和实用的周期性数据压缩方法,具有较大的应用潜力。 展开更多
关键词 数据压缩 提升格式 小波变换 火电厂
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基于提升小波和混合熵编码的数据压缩方法 被引量:12
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作者 周瑞 鲍文 +2 位作者 于霄 贺惠新 刘金福 《电力系统自动化》 EI CSCD 北大核心 2007年第22期65-69,共5页
大型发电机组远程状态监测系统中实时数据的存储与网络传输对数据压缩和重构技术提出了较高的要求。文中给出一种提升小波变换与混合熵编码技术相结合的数据压缩方法。首先利用基于提升格式的双正交滤波器组对实时数据进行小波分解,然... 大型发电机组远程状态监测系统中实时数据的存储与网络传输对数据压缩和重构技术提出了较高的要求。文中给出一种提升小波变换与混合熵编码技术相结合的数据压缩方法。首先利用基于提升格式的双正交滤波器组对实时数据进行小波分解,然后对小波系数进行阈值量化,最后通过混合熵编码技术对保留的系数进行编码,以进一步提高压缩效率。对实际发电机组实时数据进行了压缩试验,结果表明,有损压缩技术和无损压缩技术的结合可以获得较高的压缩比,能够较好地满足大型发电机组实时数据的存储和传输需求,是一种有效和实用的实时数据压缩方法。 展开更多
关键词 发电机组监测 数据压缩 小波变换 提升格式 熵编码
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