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基于三维小波变换嵌入式视频压缩算法的研究 总被引:8,自引:0,他引:8
本文把二维图像的等级树集分割编码方法(SPIHT)推广应用于三维的视频编码中,提出了一种用于三维视频序列图像的扩展等级树集分割编码方法.此方法所编码码流是嵌入式码流,在解码端可随意截取一段码流解码以达到所要求的码率和视频质量.另外此方法无需进行运动补偿,降低了算法的复杂度.通过理论分析和仿真实验得出,此方法有很好的编码效率,但对于帧内图像较复杂的序列,编码效率有所下降. 相似文献
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小波图像编码研究与应用的新进展 总被引:1,自引:0,他引:1
首先回顾了现代小波编码的发展历程,以嵌入式零树小波编码(EZW)算法和分层树中的集分割(SPIHT)编码算法为例,对其基础理论和基础思路进行了深入阐述,介绍了该领域的一些新的应用和研究成果,并分析指出了小波图像编码算法进一步改进的研究方向。 相似文献
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Choi等[1]提出的运动补偿三维子带编码方法是一种具有代表性的高效小波视频编码方法,其编码效率优于国际标准MPEG-2.但是该方法的运算复杂度高,编码时也没有充分利用小波图像的特点.为此,本文对该方法的两项关键技术进行了改进:采用像素域降采样运动估计技术以降低运算复杂度,采用改进的集分裂分层树(Set Partitioning in Hierarchical Trees,SPIHT)方法对三维时/空子带进行更高效的编码.实验结果表明,与原有的算法相比,本文的工作不仅降低了运算复杂度,也进一步提高了编码效率. 相似文献
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本文提出了等级树集合分区算法(SPIHT)的一种改进方案,对图像的小波变换域的三个空间方向(水平、垂直和对角)上的系数构成等级树型结构,并对各空间方向等级树单独进行编码,使得在不影响恢复图像质量的情况下,进一步提高压缩比.仿真实验表明了本算法的有效性. 相似文献
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随着互联网的普及和图像应用范围的不断扩大,对静止图像的编解码算法的新的要求在不断提出,即要求在较高的压缩比基础上实现更多新的功能,如嵌入式编解码、从有损压缩到无损压缩等等。嵌入式零树小波编码(EZW),及在其基础上涌现出许多新的改进算法,如分层树的集分割算法(SPIHT),集分割的嵌入块编码(SPECK),最佳截断的嵌入式块编码(EBCOT)等,文中对这些算法的原理和性能进行了讨论,并说明了静止图像编解码的研究方向。 相似文献
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空时移位键控(space-time shift keying,STSK)是一种用于多输入多输出(multi-input multi-output, MIMO)通信系统的调制方案,通过预先设计的色散矩阵集(dispersion matrix set,DMS)以实现系统在复用与分集之间的灵活设计。提出了改进的遗传算法(genetic algorithm,GA)辅助DMS和3D星座的联合优化,即将DMS和3D星座联合编码作为GA的染色体,并采用秩与行列式准则对应的编码增益作为总体适应度值。通过高效的选择以及改进的变异和交叉策略,可以获得低误码率(bit error rate,BER)的DMS和3D星座,同时利用3D星座的对称性,大幅度降低了编码增益对应的适应度值的计算复杂度。推导了3D STSK方案的理论平均成对差错概率(ABEP)。仿真结果表明,与传统的 GA 和随机搜索方案相比,本文提出的改进 GA在保证BER性能前提下可以显著降低系统实现的复杂度。 相似文献
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三维小波多分等级树视频压缩编码 总被引:2,自引:0,他引:2
提出了基于三维小波多发等级树视频压缩编码方法。通过将原始图象序列进行帧分组,并对每个图象帧组在时间、水平和垂直三维空间上进行小波变换。然后,对变换域的各个空间-时间频率了带按照其方向的不同。构成多个小波等级树,并对每个等级树分别进行SPIHT编码算法。仿真实验表明了该方法的有效性。 相似文献
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Ashraf A. Kassim Eng Hong Tan Wei Siong Lee 《Circuits, Systems, and Signal Processing》2009,28(1):41-53
This paper introduces the 3D color set partitioning in hierarchical trees (3D-CSPIHT) low bit rate embedded video coding scheme.
The codec exploits the correlation between temporal and spatial wavelet coefficients and the interdependency between luminance
and chrominance components to code color video sequences without the need for explicit bit allocation. Besides offering rate
scalability, the new codec also produces multi-resolution scalable code streams. The hierarchical variable size block matching
motion estimation technique is also integrated to demonstrate the motion estimation option with 3D-CSPIHT. The coding results
show that 3D-CSPIHT produces better performance and visual quality compared to 3D-SPIHT. 相似文献
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《Journal of Visual Communication and Image Representation》1999,10(2):173-185
We extend the work of Sherwood and Zeger to progressive video coding for noisy channels. By utilizing a three-dimensional (3D) extension of the set partitioning in hierarchical trees (SPIHT) algorithm, we cascade the resulting 3D SPIHT video coder with the rate-compatible punctured convolutional channel coder for transmission of video over a binary symmetric channel. Progressive coding is achieved by increasing the target rate of the 3D embedded SPIHT video coder as the channel condition improves. The performance of our proposed coding system is acceptable at low transmission rate and bad channel conditions. 相似文献
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Lossy-to-lossless compression of medical volumetric data using three-dimensional integer wavelet transforms 总被引:4,自引:0,他引:4
We study lossy-to-lossless compression of medical volumetric data using three-dimensional (3-D) integer wavelet transforms. To achieve good lossy coding performance, it is important to have transforms that are unitary. In addition to the lifting approach, we first introduce a general 3-D integer wavelet packet transform structure that allows implicit bit shifting of wavelet coefficients to approximate a 3-D unitary transformation. We then focus on context modeling for efficient arithmetic coding of wavelet coefficients. Two state-of-the-art 3-D wavelet video coding techniques, namely, 3-D set partitioning in hierarchical trees (Kim et al., 2000) and 3-D embedded subband coding with optimal truncation (Xu et al., 2001), are modified and applied to compression of medical volumetric data, achieving the best performance published so far in the literature-both in terms of lossy and lossless compression. 相似文献
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A simple but efficient pre-processing step for SPIHT (set partitioning in hierarchical trees) image coding is proposed. It reduces the computational complexity and increases the performance for lossy image coding 相似文献
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Error-resilient SPIHT image coding 总被引:2,自引:0,他引:2
Shih-Hsuan Yang Tsung-Chao Cheng 《Electronics letters》2000,36(3):208-210
The authors develop an efficient error-resilient scheme for the set partitioning in hierarchical trees (SPIHT) technique, one of the most successful image compression algorithms. By partitioning the coded data sequence and adding appropriate side information, the proposed algorithm provides significantly better PSNR performance over noisy channels with a minimal increase in the coding complexity 相似文献
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一般基于感兴趣区域(ROI)的图像编码算法都没有充分考虑人眼视觉特性,在分析了JPEG2000中感兴趣区域编码的优缺点后,利用小波变换的特点并结合人眼视觉的掩蔽效应,提出了一种改进的ROI图像编码算法。首先将图像小波域中的所有低频系数进行移位处理,而对于小波域中的高频系数,仅对其属于ROI区域的系数进行移位处理,再利用等级树集合分割(SPIHT)算法进行编码传输。仿真实验证明了该算法比原有算法的图像主观质量更好。 相似文献
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The application of multiwavelet transform to image coding 总被引:3,自引:0,他引:3
Gang Lin Ze-Min Liu 《IEEE transactions on image processing》2000,9(2):270-273
This work presents a new image coding scheme based on multiwavelet filter banks. First, two dimensional (2-D) multiwavelet decomposition is performed on the original image. Then, several hierarchical trees are constructed in the transform domain, and an extension of set partitioning in hierarchical trees algorithm is proposed to quantize multiwavelet coefficients. Our simulation shows that this scheme is effective and promising. 相似文献
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头肩序列图像是可视电话、会议电视等视频业务中常见的一种图像模式.本文将SPIHT算法与人脸检测算法相结合,提出一种嵌入式的头肩图像编码方法.首先采用人脸检测技术确定头肩图像中的人脸区域;然后产生人脸区的掩膜,并对LL子带中人脸区掩膜内的小波系数进行定标,以保证人脸区的小波系数能优先编码;最后采用SPIHT算法对人脸区和背景区进行编码.实验结果表明,与原来的SPIHT方法相比,这种方法可以保证人脸区域的重建质量好于背景区的重建图像.同时压缩后的码流仍然具有嵌入的特性,支持渐进传输. 相似文献
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Unequal error protection of SPIHT encoded image bit streams 总被引:11,自引:0,他引:11
Alatan A.A. Zhao M. Akansu A.N. 《Selected Areas in Communications, IEEE Journal on》2000,18(6):814-818
A derivative of the set partitioning into hierarchical trees (SPIHT) image coding method, which generates substreams with different error-resilience properties, is proposed. By dividing the image bit stream into three classes, substreams with different immunity properties are obtained. The unequal protection of these substreams with different channel coding rates improves the overall performance of the method against channel errors. Simulation results show the superiority of the proposed method over some of the state-of-the-art methods 相似文献