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MULTI-SPECTRAL AND HYPERSPECTRAL IMAGE FUSION USING 3-D WAVELET TRANSFORM 被引量:6
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作者 Zhang Yifan He Mingyi 《Journal of Electronics(China)》 2007年第2期218-224,共7页
Image fusion is performed between one band of multi-spectral image and two bands of hyperspectral image to produce fused image with the same spatial resolution as source multi-spectral image and the same spectral reso... Image fusion is performed between one band of multi-spectral image and two bands of hyperspectral image to produce fused image with the same spatial resolution as source multi-spectral image and the same spectral resolution as source hyperspeetral image. According to the characteristics and 3-Dimensional (3-D) feature analysis of multi-spectral and hyperspectral image data volume, the new fusion approach using 3-D wavelet based method is proposed. This approach is composed of four major procedures: Spatial and spectral resampling, 3-D wavelet transform, wavelet coefficient integration and 3-D inverse wavelet transform. Especially, a novel method, Ratio Image Based Spectral Resampling (RIBSR)method, is proposed to accomplish data resampling in spectral domain by utilizing the property of ratio image. And a new fusion rule, Average and Substitution (A&S) rule, is employed as the fusion rule to accomplish wavelet coefficient integration. Experimental results illustrate that the fusion approach using 3-D wavelet transform can utilize both spatial and spectral characteristics of source images more adequately and produce fused image with higher quality and fewer artifacts than fusion approach using 2-D wavelet transform. It is also revealed that RIBSR method is capable of interpolating the missing data more effectively and correctly, and A&S rule can integrate coefficients of source images in 3-D wavelet domain to preserve both spatial and spectral features of source images more properly. 展开更多
关键词 Image fusion 3-dimensional 3-d wavelet transform MULTI-SPECTRAL HYPERSPECTRAL
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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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AN ALGORITHM FOR CODING VIDEO SIGNAL BASED ON 3-D WAVELET TRANSFORMATION
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作者 Wu Peng Zhang Miaolan Li Xianglin (Dept. of Electrical Eng., Graduate School, Uni. of Sci. and Tech. of China, Beijing 100039) 《Journal of Electronics(China)》 2000年第2期97-107,共11页
This paper presents an algorithm for coding video signal based on 3-D wavelet transformation. When the frame order t of a video signal is replaced by order 2, the video signal can be looked as a block in 3-D space. Af... This paper presents an algorithm for coding video signal based on 3-D wavelet transformation. When the frame order t of a video signal is replaced by order 2, the video signal can be looked as a block in 3-D space. After splitting the block into smaller sub-blocks, imitate the method of 2-D wavelet transformation for images, we can transform the sub-blocks with 3-D wavelet. Most of video signal energy is in the decomposed low-frequency sub-bands. These sub-bands affect the visual quality of the video signal most. Quantizing different sub-bands with different precision and then entropy encoding each sub-band, we can eliminate inter- and intra-frame redundancy of the video signal and compress data. Our simulation experiments show that this algorithm can achieve very good result. 展开更多
关键词 waveletS 3-d wavelet transformATION VIDEO signal CODING
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3-D Wavelet Transform for Very Low Bit-Rate Video Coding
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作者 Hou Weidong Mo Yulong Zhu Qiuyu Wei Chunlong (Shool of Communication and Information Engineering, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第2期48-51,共4页
A new improved Goh's 3 D wavelet transform(WT) coding scheme is presented in this paper. The new scheme has great advantages including a simple code structure, low computation cost and good performance in PSNR, c... A new improved Goh's 3 D wavelet transform(WT) coding scheme is presented in this paper. The new scheme has great advantages including a simple code structure, low computation cost and good performance in PSNR, compression ratios and visual quality of reconstructions, when compared to the other existing 3 D WT coding methods and the 2 D WT based coding methods. The new 3 D WT coding scheme is suitable for very low bit rate video coding. 展开更多
关键词 video coding video compression very low bit rate 3 D wavelet transform
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Multiple description scalable video coding based on 3D lifted wavelet transform 被引量:3
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作者 KIM Yong-deak 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期857-863,共7页
In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multi... In this work, a new method to deal with the unconnected pixels in motion compensated temporal filtering (MCTF) is presented, which is designed to improve the performance of 3D lifted wavelet coding. Furthermore, multiple description scalable coding (MDSC) is investigated, and novel MDSC schemes based on 3D wavelet coding are proposed, using the lifting imple- mentation of temporal filtering. The proposed MDSC schemes can avoid the mismatch problem in multiple description video coding, and have high scalability and robustness of video transmission. Experimental results showed that the proposed schemes are feasible and adequately effective. 展开更多
关键词 Multiple DESCRIPTION SCALABLE coding (MDSC) MOTION compensated temporal filtering (MCTF) Block-split bidi-rectional MOTION estimation 3D lifted wavelet transform
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The Parameter Determination in the Design of 3-D Spherically Symmetric FIR Filters via the McClellan Transformation 被引量:1
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作者 Jin Xiaoying Li Jixing Chen Shuzhen 《Wuhan University Journal of Natural Sciences》 CAS 1998年第1期65-70,共6页
In the design of 3-D spherically symmetric FIR filters via the McClellan transformation, two methods are proposed to determine the transformation parameters. The first is to improve the original 3-D algorithm by explo... In the design of 3-D spherically symmetric FIR filters via the McClellan transformation, two methods are proposed to determine the transformation parameters. The first is to improve the original 3-D algorithm by exploiting the 2-D effective methods in 3-D. This method can change the constrained optimization algorithm into the unconstrained one and makes the design easier to realize. The second method is to solve the coupled equations under constrained conditions and a set of ideal parameters can be gotten. The design example shows that the two methods are all efficient and easier than the original algorithm. 展开更多
关键词 McClellan transformation optimization algorithm 3-d digital filters
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Very Low Bit Rate Video Coding Using Motion Compensated 3 D Wavelet Transform
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作者 HOU Wei dong MO Yu long (School of Communication and Information Engineering, Shanghai University) HU Hai ping (School of Sciences, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第4期342-344,共3页
A new motion compensated 3 D wavelet transform (MC 3DWT) video coding scheme is presented in this paper. The new coding scheme has a good performance in average PSNR, compression ratio and visual quality of reconst... A new motion compensated 3 D wavelet transform (MC 3DWT) video coding scheme is presented in this paper. The new coding scheme has a good performance in average PSNR, compression ratio and visual quality of reconstructions compared with the existing 3 D wavelet transform (3DWT) coding methods and motion compensated 2 D wavelet transform (MC WT) coding method. The new MC 3DWT coding scheme is suitable for very low bit rate video coding. 展开更多
关键词 video coding very low bit rate 3 D wavelet transform motion compensation
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Synchronization of two 3-scroll hyperchaotic attractors using wavelet transform
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作者 Li Jian Zhou Jiliu Wang Yong Zhi Yong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期387-389,共3页
The synchronization of two 3-scroll hyperchaotie attractors is realized based on wavelet transform and single variables' feedstock. In the transmitter, one signal is decomposed by wavelet transform and the detailed i... The synchronization of two 3-scroll hyperchaotie attractors is realized based on wavelet transform and single variables' feedstock. In the transmitter, one signal is decomposed by wavelet transform and the detailed information is removed, then the component with low frequency is reconstructed and sent into the channel In the receiver, the received signal is used as the feedback signal to realize the synchronization of two chaotic systems. Using this synchronous method, the transmitting signal is transported in compressible way, the system resource is saved, furthermore, because the transported signal is not a whole chaotic signal, the performance of security of the system is improved. 展开更多
关键词 wavelet transform 3-scroll hyperehaotie attractor SYNCHRONIZATION single variable's feedback.
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Defects Recognition of 3D Braided Composite Based on Dual-Tree Complex Wavelet Packet Transform
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作者 贺晓丽 王瑞 《Journal of Donghua University(English Edition)》 EI CAS 2015年第5期749-752,共4页
Textile-reinforced composites,due to their excellent highstrength-to-low-mass ratio, provide promising alternatives to conventional structural materials in many high-tech sectors. 3D braided composites are a kind of a... Textile-reinforced composites,due to their excellent highstrength-to-low-mass ratio, provide promising alternatives to conventional structural materials in many high-tech sectors. 3D braided composites are a kind of advanced composites reinforced with 3D braided fabrics; the complex nature of 3D braided composites makes the evaluation of the quality of the product very difficult. In this investigation,a defect recognition platform for 3D braided composites evaluation was constructed based on dual-tree complex wavelet packet transform( DT-CWPT) and backpropagation( BP) neural networks. The defects in 3D braided composite materials were probed and detected by an ultrasonic sensing system. DT-CWPT method was used to analyze the ultrasonic scanning pulse signals,and the feature vectors of these signals were extracted into the BP neural networks as samples. The type of defects was identified and recognized with the characteristic ultrasonic wave spectra. The position of defects for the test samples can be determined at the same time. This method would have great potential to evaluate the quality of 3D braided composites. 展开更多
关键词 3D braided composite dual-tree complex wavelet packet transform(DT-CWPT) ultrasonic wave
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Digital Beamforming by Multiple Chirp Zeta Transforms for 3-D Sonar Imaging Systems
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作者 袁龙涛 田翔 +1 位作者 韩业强 陈耀武 《Journal of Donghua University(English Edition)》 EI CAS 2012年第5期373-379,共7页
The computational load is prohibitive for real-time image generation in 3-D sonar systems, particularly when the steering angle approximation is required. In this paper, a novel multiple Chirp Zeta Transforms (MCZT)... The computational load is prohibitive for real-time image generation in 3-D sonar systems, particularly when the steering angle approximation is required. In this paper, a novel multiple Chirp Zeta Transforms (MCZT) beamforming method in frequency domain is being proposed. The single long-length Chirp Zeta Transform (CZT) in the original CZT beamforming is replaced by several CZTs with smaller lengths for different partitions along each dimension. The implementing routine of the algorithm is also optimized. Furthermore, an avenue to evaluate the estimating error for the angle approximation in 3-D imaging applications is presented, and an approach to attain valid partitions for the steering angles is also flhistrated. This paper demonstrates a few advantages of the proposed frequency-domain beamforming method over existing methods in terms of the computatianal complexity. 展开更多
关键词 3-d sonar imaging frequency-domain beamforming angle approximation Chirp Zeta transform CZT steering angle partitions computational load evaluation
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基于小波变换的显微图像清晰度评价函数及3-D自动调焦技术 被引量:25
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作者 王义文 刘献礼 谢晖 《光学精密工程》 EI CAS CSCD 北大核心 2006年第6期1063-1069,共7页
提出了基于小波变换的图像清晰度评价函数。采用大NA(数值孔径)和小NA的显微图像序列,比较分析了本文提出的评价函数和经典的归一化方差函数、熵函数、能量拉普拉斯函数以及另外两种基于小波变换评价函数的清晰度评价性能。同时采用带... 提出了基于小波变换的图像清晰度评价函数。采用大NA(数值孔径)和小NA的显微图像序列,比较分析了本文提出的评价函数和经典的归一化方差函数、熵函数、能量拉普拉斯函数以及另外两种基于小波变换评价函数的清晰度评价性能。同时采用带有标准偏差为25的高斯噪声显微图像序列,比较了这五种评价函数的抗噪能力。实验结果表明:提出的评价函数具有最高的聚焦精度和聚焦分辨率,且具有与抗噪能力最强的归一化方差函数相当的抗噪能力。提出了基于区域选择的自动聚焦方法,实现了处于不同深度的微操作对象的3-D自动聚焦。该评价函数和区域选择聚焦技术可以用于高精度的自动微操作作业中。进一步说明自动调焦是实现自动化微操作的关键技术,而其核心是清晰度评价函数的选取或构建。 展开更多
关键词 自动调焦 清晰度评价函数 小渡变换 3-d自动调焦
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基于3-D整数小波变换的视频压缩算法研究
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作者 周武 傅忠谦 +1 位作者 朱晓鸣 周学友 《计算机工程与应用》 CSCD 北大核心 2006年第35期55-57,60,共4页
视频图像数据可以被看成三维数据体来进行3-D小波变换,对变换后的数据进行编码就可以达到压缩视频数据的目的。主要讨论了这种变换的整数实现方法,以及对小波系数使用SPIHT算法进行编码压缩,并对SPIHT算法进行了有针对性的优化。仿真实... 视频图像数据可以被看成三维数据体来进行3-D小波变换,对变换后的数据进行编码就可以达到压缩视频数据的目的。主要讨论了这种变换的整数实现方法,以及对小波系数使用SPIHT算法进行编码压缩,并对SPIHT算法进行了有针对性的优化。仿真实验证明,该文方法压缩效果良好,运行效率高,输出码流具有嵌入式特性,是一种有应用前景的算法。 展开更多
关键词 3-d整数小波变换 视频压缩 小波系数编码
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Automated Phase-measuring Profilometry of 3-D Diffuse Objects Using a Single Phase Step Method 被引量:2
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作者 ZHAO Hong,SONG Yuanhe,CHEN Wenyi,TAN Yushan (Research Institute for Laser & Infrared Application, Xi’an Jiaotong University,Xi’an 710049,CHN) 《Semiconductor Photonics and Technology》 CAS 1998年第1期25-30,35,共7页
The technique of phase measuring profilometry using a single phase step method is proposed.This method can automatically obtain phase value at each pixel by using a discret cosine transform algorithm.The method is abl... The technique of phase measuring profilometry using a single phase step method is proposed.This method can automatically obtain phase value at each pixel by using a discret cosine transform algorithm.The method is able to automatically recognize any position between depression and elevation on an object surface.Theoretical analysis and experimental verification are presented. 展开更多
关键词 Discret Cosine transform Noncontact Optical Measurement One Step Phase-shifting Phase-measuring 3-d Profilometry
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DESIGN AND IMPLEMENTATION OF A 3-DIMENSIONAL COMPUTER AIDED GARMENT DESIGN SYSTEM
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作者 朱辉 萧众 《Journal of China Textile University(English Edition)》 EI CAS 1991年第2期27-33,共7页
A 3-Dimensional computer aided garment design (CAGD) system has been developed andimplemented on a high-performance workstation. We studied various approaches to the func-tional modelling of garment designs for the sy... A 3-Dimensional computer aided garment design (CAGD) system has been developed andimplemented on a high-performance workstation. We studied various approaches to the func-tional modelling of garment designs for the system. According to the characteristic data of a hu-man body, the models of human body and the garment are displayed on the screen, then we canmodify the garment with various styles and different sizes. The system can transform the 3-Dgarment to the 2-D pieces. The system has improved design efficiency. Various potential alterna-tives and improvement of the system have also been studied and explored. 展开更多
关键词 GARMENTS 3D-computer-aided design MODEL MODEL of human BODY MODEL of GARMENT transformation of the 3-d GARMENT to the 2-d pieces
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3-D CONSOLIDATION ANALYSIS OF LAYERED SOIL WITH ANISOTROPIC PERMEABILITY USING ANALYTICAL LAYER-ELEMENT METHOD
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作者 Zhiyong Ai Yichong Cheng 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2013年第1期62-70,共9页
Starting with governing equations of a saturated soil with anisotropic permeability and based on multiple integral transforms, an analytical layer-element equation is established explicitly in the Laplace-Fourier tran... Starting with governing equations of a saturated soil with anisotropic permeability and based on multiple integral transforms, an analytical layer-element equation is established explicitly in the Laplace-Fourier transformed domain. A global matrix of layered soil can be obtained by assembling a set of analytical layer-elements, which is further solved in the transformed domain by considering boundary conditions. The numerical inversion of LaplaceFourier trans- form is employed to acquire the actual solution. Numerical analysis for 3-D consolidation with anisotropic permeability of a layered soil system is presented, and the influence of anisotropy of permeability on the consolidation behavior is discussed. 展开更多
关键词 analytical layer-element 3-d consolidation anisotropic permeability multiple integral transforms
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一种新的3-D小波变换图像编码方法 被引量:9
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作者 张文忠 沈兰荪 《电子学报》 EI CAS CSCD 北大核心 1997年第10期32-36,共5页
基于图像序列三维小波变换的视频编码技术是一种很有潜力的编码方法.本文针对目前实际中采用的三维小波变换只是一种准三维变换,不能提供对变换结果的统一描述等不足,推导了信号真正的三维小波变换的有关理论及其实现方法.在此基础... 基于图像序列三维小波变换的视频编码技术是一种很有潜力的编码方法.本文针对目前实际中采用的三维小波变换只是一种准三维变换,不能提供对变换结果的统一描述等不足,推导了信号真正的三维小波变换的有关理论及其实现方法.在此基础上,我们将这种三维小波变换方法用于视频图像的编码,模拟结果表明这种编码结构具有良好性能,值得进一步的深入研究. 展开更多
关键词 视频图像编码 3-d小波变换 多分辨率分析
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纯二维5/3小波变换及其在CT图像无损压缩中的应用 被引量:3
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作者 徐妮妮 张明明 汪剑鸣 《电信科学》 北大核心 2016年第6期73-82,共10页
小波变换在数字图像处理领域有着广泛的应用,其对图像的处理常采用行列分离处理方式,这种方式不能完全吻合人眼视觉特性。针对这一情况,构造了一种与人眼视觉特性更加吻合的纯二维小波变换处理方式。首先,由一维5/3小波滤波器组通过Mc C... 小波变换在数字图像处理领域有着广泛的应用,其对图像的处理常采用行列分离处理方式,这种方式不能完全吻合人眼视觉特性。针对这一情况,构造了一种与人眼视觉特性更加吻合的纯二维小波变换处理方式。首先,由一维5/3小波滤波器组通过Mc Clellan变换构造纯二维5/3小波滤波器组,并用提升格式实现;然后,用该提升格式与纯二维Lazy小波滤波器组相嵌套的形式实现图像的纯二维5/3小波变换。为了便于工程应用,给出了其变换规程。将纯二维5/3小波变换用于CT图像的无损压缩,实验证明:对于512 dpi×512 dpi尺寸的CT图像,纯二维5/3小波变换无损压缩效果高于二维可分离5/3小波变换,每幅图像可平均节省1 989.9 byte。 展开更多
关键词 人眼视觉系统 McClellan变换 提升格式 纯二维5/3小波变换 无损压缩
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基于改进3D SPIHT的MRI序列图像压缩方法 被引量:1
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作者 蒋行国 李丹 陈真诚 《航天医学与医学工程》 CAS CSCD 北大核心 2013年第2期120-124,共5页
目的研究一种有效的MRI序列图像压缩方法。方法以2组不同数量、不同层厚的MRI序列图像为例,针对3D SPIHT算法运算复杂度,在对D型、L型表项重复判断的不足上,提出了一种改进的3DSPIHT方法;同时,根据MRI序列图像的相关性特点,提出了分组编... 目的研究一种有效的MRI序列图像压缩方法。方法以2组不同数量、不同层厚的MRI序列图像为例,针对3D SPIHT算法运算复杂度,在对D型、L型表项重复判断的不足上,提出了一种改进的3DSPIHT方法;同时,根据MRI序列图像的相关性特点,提出了分组编/解码的方法,结合3D小波变换和应用改进的3D SPIHT方法,实现了MRI序列图像压缩。结果分组结合改进3D SPIHT方法与2DSPIHT,3D SPIHT相比,能够得到较好重构图像,同时,峰值信噪比(PSNR)提高了1~8 dB左右。结论在相同码率下,分组结合改进3D SPIHT的方法提高了PSNR和图像恢复质量,可以更好地解决大量MRI序列图像存储与传输问题。 展开更多
关键词 磁共振图像 3D小波变换 3D SPIHT算法 图像压缩
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基于5/3小波变换的木材纹理频域特征研究 被引量:2
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作者 高峰 多化琼 王亚超 《内蒙古农业大学学报(自然科学版)》 CAS 北大核心 2013年第3期155-158,共4页
通过利用整数5/3小波变换,对木材纹理进行多尺度分解,利用特征参数分析了木材纹理频率分布特征,比较了针叶材与阔叶材、径向与弦向切面的木材纹理的差异。实验结果表明,利用整数5/3小波变换,分析各子图像能量值的标准差,筛选出木材纹理... 通过利用整数5/3小波变换,对木材纹理进行多尺度分解,利用特征参数分析了木材纹理频率分布特征,比较了针叶材与阔叶材、径向与弦向切面的木材纹理的差异。实验结果表明,利用整数5/3小波变换,分析各子图像能量值的标准差,筛选出木材纹理最佳分解尺度为2,同时还发现小波能量分布比例和EHL/ELH值可作为木材纹理方向性参数。 展开更多
关键词 木材纹理 5 3小波变换 频域特征参数
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基于FPGA的5/3提升小波优化算法 被引量:1
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作者 陈占良 金龙旭 +2 位作者 陶宏江 韩双丽 张敏 《电视技术》 北大核心 2015年第11期113-116,共4页
为了实现线阵CCD空间相机图像的实时压缩处理,在提升算法的基础上,提出了一种适用于FPGA的二维提升小波变换结构与实现方案。该系统利用FPGA片内的存储资源,采用乒乓操作实现了行列变换之间的数据缓存传输,降低了功耗,提高了硬件利用率... 为了实现线阵CCD空间相机图像的实时压缩处理,在提升算法的基础上,提出了一种适用于FPGA的二维提升小波变换结构与实现方案。该系统利用FPGA片内的存储资源,采用乒乓操作实现了行列变换之间的数据缓存传输,降低了功耗,提高了硬件利用率和运算速度。并且为了适应硬件实现速度,在进行小波边界处理时不需要额外的边界延拓过程,很大程度上降低了算法的复杂度;整个模块采用verilog HDL语言进行设计,并在Questa Sim下进行了仿真试验。实验结果表明,该系统工作稳定可靠,完全满足实时处理的要求,并适用于JPEG2000的多级二维5/3小波变换。 展开更多
关键词 实时压缩 提升算法 流水线结构 5/3小波变换 FPGA
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