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Fast 2-D 8×8 discrete cosine transform algorithm for image coding

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Science in China(Series F) 2009年第2期52卷 215-225页

作者： JI XiuHua ZHANG CaiMing WANG JiaYe BOEY S. H. Fast 2-D 8×8 discrete cosine transform algorithmfor image coding1 School of Computer Science and Technology Shandong Economic University Jinan 250014 China School of Computer Science and Technology Shandong University Jinan 250061 China

A new fast two-dimension 8×8 discrete cosine transform （2D 8×8 DCT） algorithm based on the characteristics of the basic images of 2D DCT is presented. The new algorithm computes each DCT coefficient in turn more independently. Hence, the new algorithm is suitable for 2D DCT pruning algorithm of pruning away any number of high-frequency components of 2D DCT. The proposed pruning algorithm is more efficient than the existing pruning 2D DCT algorithms in terms of the number of arithmetic operations, especially the number of multiplications required in the computation.

关键词： discrete cosine transform basic image quantization image coding

Lifting Scheme Based SPIHT Still image coding

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Journal of Beijing Institute of Technology 2003年第S1期12卷 70-74页

作者：沈利军赵保军何佩琨 Department of Electronic Engineering School of Information Science and TechnologyBeijing Institute of TechnologyBeijing 100081China

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.

关键词： SPIHT lifting scheme wavelet image coding

A New image coding Algorithm Based on Self-Organizing Neural Network

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The Journal of China Universities of Posts and Telecommunications 1995年第1期2卷 40-43页

作者： LiHongsong QuanZiyi DepartmentofRadioEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100088P.R.China De

The paper deals with a new VQ+DPCM+DCT algorithm based on Self-Organizing Feature Maps(SOFM) algorithm for image coding. In addition. a Frequency sensitive SOFM (FSOFM) has been also devel-oped. Simulation results sh... 详细信息

关键词： image coding vector quantization (VQ),self-organizing neural network

Generalized Partial Bitplanes Shift Method for JPEG2000 Region-of-Interest image coding

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Generalized Partial Bitplanes Shift Method for JPEG2000 Regi...

第三届国际仪器科学技术学术研讨会

作者： LIANG Yan LIU Wen-yao College of Precision Instruments and Opto-electronic Engineering P.O.Box 235 Tianjin University Tianjin 300072 China

In order to complement the two standard methods defined in JPEG2000, a new region-of-interest (ROI) coding method called generalized partial bitplanes shift (GPBShift) is presented . To control the re

关键词： region-of-interest (ROI) image coding JPEG2000 generalized partial bitplanes shift (GPBShift)

Low-complexity multiple ROI image coding method based on different degrees of interest

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Low-complexity multiple ROI image coding method based on dif...

2007亚洲光电子会议电子成像与多媒体技术分会场

Multiple Region of Interest （ROI） coding is important in applications where some parts of the image are of higher importance than others and need to be encoded at higher quality than the background. The new image coding standard JPEG2000 recommended the Maxshift method to complete ROI coding. However, the drawback of the Maxshift method is that the coefficient bitplanes of all ROIs must be scaled with the same values, which cannot code ROIs according to different degrees of interest. This paper describes a flexible multiple ROI coding scheme called BTShift （Bitplane Twice Shift）. The proposed method uses different bitplane scaling strategies between low frequency subbands and high frequency subbands. Experimental results on several state-of-the-art images show that the new scheme does not only support multiple ROI coding according to different degrees of interest, but also can encode the ROIs and background without their shape information. Additionally, BTShift is compliant with the recommended Maxshift method. So we hope the proposed method can be valuable for the remote sensing image compression and medical image coding in the future.

关键词： image coding JPEG2000 region of interest degree of interest bitplane twice shift

Lossless image coding via One-Dimensional Grammar Based Codes

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Lossless Image Coding via One-Dimensional Grammar Based Code...

2000 International Conference on Communication Technology(WCC2000·ICCT2000)

作者： En-hui Yang Jianghong Guo Department of Electrical and Computer Engineering University of Waterloo WaterlooON N2L 3G1Canada

ISBN: (纸本)0780363949

＜正＞In this paper,lossless image coding is considered from an information theoretic point of *** new coding schemes are *** the first,coding scheme,an image is first scanned in a quadrant by quadrant manner and then encoded by using a one-dimensional grammar based code which has been developed recently by Yang and Kieffer and is called the improved sequential algorithm（or simply the YK algorithm）.In the second coding scheme,an image is first,predicted by using a context template, then scanned in a quadrant by quadrant manner,and finally encoded by using the YK *** the third coding scheme,an image is first scanned in a quadrant by quadrant manner and then encoded by using a modified YK algorithm,which also includes a 2-D arithmetic code as an option to remove local 2-D *** of the nature of the YK algorithm and the scanning method,all three coding schemes can remove effectively global redundancy existing in ***,it is proved that all three coding schemes are universal and outperform asymptotically any finite 2-D block code and any finite context 2-D arithmetic code as the image size gets larger and *** small images,however,the second coding scheme is slightly more effective in removing local redundancy occurring in images than does the first,coding scheme,and the third one is the best among the *** results on bi-level images confirm our theoretic results:for images of size 512×512,our results are Comparable with those afforded by JBIG 1;for some images of size 1024×1024, our results are better than those afforded by JBIG1.

关键词： image coding arithmetic codes redundancy sequential codes prediction theory context-free grammars data compression lossless image coding one-dimensional codes grammar-based codes information theory improved sequential algorithm YK algorithm context template image scanning image prediction 2D arithmetic code local 2D redundancy global redundancy bi-level images 512 pixel 262144 pixel 1024 pixel 1048576 pixel

NEW CLASSIFIED VECTOR QUANTIZATION WITH QUADTREE SEGMENTATION FOR image coding

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NEW CLASSIFIED VECTOR QUANTIZATION WITH QUADTREE SEGMENTATIO...

1996 3rd International Conference on Signal Processing(ICSP’96)

作者： Shih-Hsuan YANG Shih-Shing YANG Department of Electronic Engineering National Taipei Institute of Technology Department of Mechanical Engineering National Taiwan University

ISBN: (纸本)0780329120

＜正＞A new variable block-size,classified vector quantization（VQ） scheme for image compression is presented.A quadtree segmentation is employed to generate blocks of variable size according to their *** areas are coded by a predictive VQ of low encoding rate,while active areas are coded by an edge-classified VQ to avoid edge *** the segmentation and the edge classification are determined by a simple universal contrast *** is shown that the performance of this scheme is competitive with other classified VQ-based approaches,while the coding complexity is relatively low.

关键词： image coding vector quantisation quadtrees image segmentation edge detection image classification classified vector quantization quadtree segmentation image coding variable block-size image compression predictive VQ edge-classified VQ edge classification universal contrast identifier coding complexity

The Algorithm of Fractal image Block coding Based on the Ortho Difference Sum

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The Algorithm of Fractal Image Block Coding Based on the Ort...

第25届中国控制与决策会议

作者： LI Shiping LIU Lijing College of Information Science and Engineering Northeastern University

ISBN: (纸本)9781467355339

According to the relationship between matching mean square error and ortho difference sum, range can find the best matching defined-domain within the narrower scope of search. At the same time, the defined-domain having smaller standard deviation will be excluded within the entire codebooks previously and all the ranges having smaller standard deviation will be substituted by their mean values during the decoding process. The experiments show that, the algorithm that I have come up with in this essay improves respectively four times and six times in coding speed compared with cross-track algorithm and variance algorithm, meanwhile, the peak’s signal-noise ratio of the decoded images is slightly improved.

关键词： image coding Fractal the Ortho difference sum Cross trace Variance

An Adaptive Block-Based Fractal image coding Scheme

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Journal of Beijing Institute of Technology 1996年第2期5卷 183+177-183页

作者：邓元木柯有安北京理工大学电子工程系

Based on Jacquin's work. this paper presents an adaptive block-based fractal image coding scheme. Firstly. masking functions are used to classify range blocks and weight the mean Square error (MSE) of images. Secondly, an adaptive block partition scheme is introduced by developing the quadtree partition method. Thirdly. a piecewise uniform quantization strategy is appled to quantize the luminance shifting. Finally. experiment results are shown and compared with what reported by Jacquin and Lu to verify the validity of the methods addressed by the authors.

关键词： fractal technique image compression image coding