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Multiple shell structured hypercube feature maps for vector quantization of images

SIGNAL PROCESSING-IMAGE COMMUNICATION 1996年第6期8卷 501-512页

作者： Kim, YK Ra, JB KOREA ADV INST SCI & TECHNOL DEPT ELECT ENGN YUSONG GU TAEJON 305701 SOUTH KOREA

A new neural network architecture is proposed for spatial domain image vector quantization (VQ). The proposed model has a multiple shell structure consisting of binary hypercube feature maps of various dimensions, which are extended forms of Kohonen's self-organizing feature maps (SOFMs). It is trained so that each shell can contain similar-feature vectors. A partial search scheme using the neighborhood relationship of hypercube feature maps can reduce the computational complexity drastically with marginal coding efficiency degradation. This feature is especially proper for vector quantization of a large block or high dimension. The proposed scheme can also provide edge preserving VQ by increasing the number of shells, because shells far from the origin are trained to contain edge block features.

关键词： vector quantization multiple shell structure hypercube feature maps edge preservation entropy coding

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Hierarchical partition priority wavelet image compression

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IEEE TRANSACTIONS ON IMAGE PROCESSING 1996年第7期5卷 1111-1123页

作者： Efstratiadis, SN Tzovaras, D Strintzis, MG Information Processing Laboratory Deptartment of Electrical and Computer Engineering Aristotle University of Thessaloniki Greece

Image compression methods for progressive transmission using optimal hierarchical decomposition, partition priority coding (PPC), and multiple distribution entropy coding (MDEC) are presented, In the proposed coder, a hierarchical subband/wavelet decomposition transforms the original image. The analysis filter banks are selected to maximize the reproduction fidelity in each stage of progressive image transmission. An efficient triple-state differential pulse code modulation (DPCM) method is applied to the smoothed subband coefficients, and the corresponding prediction error is Lloyd-Max quantized. Such a quantizer is also designed to fit the characteristics of the detail transform coefficients in each subband, which are then coded using novel hierarchical PPC (HPPC) and predictive HPPC (PHPPC) algorithms, More specifically, given a suitable partitioning of their absolute range, the quantized detail coefficients are ordered based on both their decomposition level and partition and then are coded along with the corresponding address map, Space filling scanning further reduces the coding cost by providing a highly spatially correlated address map of the coefficients in each PPC partition. Finally, adaptive MDEC is applied to both the DPCM and HPPC/PHPPC outputs by considering a division of the source (quantized coefficients) into multiple subsources and adaptive arithmetic coding based on their corresponding histograms, Experimental results demonstrate the great performance of the proposed compression methods.

关键词： Image coding Pulse modulation entropy coding Wavelet transforms Image analysis Filter bank Image communication Modulation coding Algorithm design and analysis Partitioning algorithms

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Optimal variable-rate mean-gain-shape vector quantization for image coding

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1996年第6期6卷 660-668页

作者： Lightstone, M Mitra, SK UNIV CALIF SANTA BARBARA CTR INFORMAT PROC RESDEPT ELECT & COMP ENGNSANTA BARBARACA 93106

A method for rate-distortion optimal variable rate mean-gain-shape vector quantization (MGSVQ) is presented with application to image compression, Conditions are derived within an entropy-constrained product code framework that result in an optimal bit allocation between mean, gain, and shape vectors at all rates, An extension to MGSVQ called hierarchical mean-gain-shape vector quantization (HMGSVQ) is similarly introduced, By considering statistical dependence between adjacent means, this method is able to provide improvement in rate-distortion performance over traditional MGSVQ, especially at low bit rates, Simulation results are provided to demonstrate the rate-distortion performance of MGSVQ and HMGSVQ for image data.

关键词： entropy codes image coding optimisation rate distortion theory statistical analysis vector quantisation HMGSVQ MGSVQ entropy constrained product code gain vectors hierarchical mean gain shape vector quantization image compression image data low bit rates image coding image data Rate distortion Vector quantization Rate distortion theory Data compression Statistical analysis Image compression entropy coding Statistical methods

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Advances in residual vector quantization: A review

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IEEE TRANSACTIONS ON IMAGE PROCESSING 1996年第2期5卷 226-262页

作者： Barnes, CF Rizvi, SA Nasrabadi, NM SUNY BUFFALO DEPT ELECT & COMP ENGN AMHERST NY 14260 USA

Advances in residual vector quantization (RVQ) are surveyed. Definitions of joint encoder optimality and joint decoder optimality are discussed, Design techniques for RVQ's with large numbers of stages and generally different encoder and decoder codebooks are elaborated and extended. Fixed-rate RVQ's, and variable-rate RVQ's that employ entropy coding are examined. Predictive and finite state RVQ's designed and integrated into neural-network based source coding structures are revisited, Successive approximation RVQ's that achieve embedded and refinable coding are reviewed, A new type of successive approximation RVQ that varies the instantaneous block rate by using different numbers of stages on different blocks is introduced and applied to image waveforms, and a scalar version of the new residual quantizer is applied to image subbands in an embedded wavelet transform coding system.

关键词： embedding approximation decoders Predictive Large Numbers entropy coding ENCODER Neural network wavelet transform coding optimality

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VIDEOcoding USING WAVELET TRANSFORM, WINDOWED MOTION COMPENSATION AND CONDITIONAL entropy coding

VIDEOCODING USING WAVELET TRANSFORM, WINDOWED MOTION COMPENS...

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Conference on Visual Communications and Image Processing 94

作者： HINDO, U SCHJORRING, S TELE DANMARK RES DK-2970 HORSHOLMDENMARK

ISBN: (纸本)081941638X

In this paper a video coding scheme is presented which is a hybrid coding scheme tailored to suit the wavelet transform. Using conventional block based motion compensation introduces blocking effects in the prediction error signal which are expensive to code when using a wavelet transform. Therefore a windowed motion compensation using overlapping blocks is used to smooth out transitions between blocks. A method for coding the quantized wavelet coefficients is presented. The positions of non-zero coefficients are coded using conditional entropy coding. The method exploits the correlation between coefficients inside a subband as well as between coefficients in different subbands. Simulation results are given for different prediction methods and different methods to code the quantized wavelet coefficients when coding an R.601 signal to 4 Mbit/s.

关键词： VIDEO coding WAVELET TRANSFORM WINDOWED MOTION COMPENSATION entropy coding

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Lattice vector quantization of image wavelet coefficient vectors using a simplified form of entropy coding

Lattice vector quantization of image wavelet coefficient vec...

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International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： A. Woolf G. Rogers Division of Radiophysics CSIRO Sydney NSW Australia

Lattice vector quantization has recently attracted some interest as an alternative to full-search VQ for signal and image coding problems. It is considerably more computationally efficient, and it avoids the difficult codebook design problem. Furthermore, it has been noted that the optimal high bit rate entropy constrained vector quantizer will approximate a lattice. Indeed for lattice VQ to be competitive, the quantized vectors should be entropy coded. This has traditionally been performed on a per image basis, a complex and inefficient process. We propose a general image-independent coding scheme which we apply to the coding of lattice quantized wavelet coefficient vectors. We also demonstrate that the quantizing and coding complexity can be reduced through reducing the dimension of the wavelet vectors by means of principal components analysis and a perceptually based nonlinearity.< >

关键词： Lattices Vector quantization Wavelet coefficients Image coding entropy coding Pixel Statistics Australia Bit rate Wavelet analysis

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Optimal entropy coding in image subband coders

Optimal entropy coding in image subband coders

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IEEE International Conference on Image Processing

作者： J.M. Lervik T.A. Ramstad Department of Telecommunication Norwegian Institute of Technology Trondheim Norway

The paper argues that the JPEG coder is based on a non-optimal entropy coding method. It is shown that for frequency domain coders using uniform quantization it is optimal to use entropy coders optimized for the entropy in each frequency component. A subband coder model with uniform quantization followed by optimal entropy coding is presented, where each subband is allocated an entropy coder based on its entropy. The theoretical coding gain limit for this model is shown to be the same as for frequency domain coders employing explicit bit allocation. However, the new model exploits the advantage associated with variable length coding. In addition, it is possible to efficiently use midtread quantizers, which have higher mean square error performance and, more important, better visual performance than midrise quantizers. Advantages for practical subband image coders are discussed in the paper.< >

关键词： entropy coding Image coding Transform coding Frequency domain analysis Bit rate Signal resolution Quantization Finite impulse response filter Filter bank Distortion

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A prediction strategy for efficient entropy coding of VQ addresses

A prediction strategy for efficient entropy coding of VQ add...

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IEEE International Symposium on Information Theory

作者： S. Fioravanti D.D. Giusto DIBE University of Genova Italy Institute of Electrical Engineering University of Cagliari Italy

A novel predictive coding scheme is presented where the residual correlations between VQ contiguous blocks are exploited by a neural predictor. A further compression is then achieved via a dynamic codebook reordering ... 详细信息

关键词： entropy coding Neural networks Decoding Image coding Bit rate Histograms Predictive coding Vector quantization Approximation methods Image reconstruction

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Very high speed entropy coding

Very high speed entropy coding

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IEEE International Conference on Image Processing

作者： M. Boliek J.D. Allen E.L. Schwartz M.J. Gormish RICOH California Research Center Menlo Park CA USA

Efforts to build high-speed hardware for many different entropy coders are limited by fundamental feedback loops. A method that allows for parallel compression in hardware is described. This parallelism results in extremely high rates, 100 million symbols/second or higher. The system is generalizable to any lossless or lossy system with deterministic decompression. Prototype hardware that divides the data into multiple streams that feed parallel coders is presented. The problem of efficient transmission of multiple streams of variable-length coded data is solved by a unique coded data interleave method.< >

关键词： entropy coding Hardware Decoding Feedback loop Interleaved codes Huffman coding Prototypes Feeds Streaming media Automata

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Lossless compression of multi-dimensional medical image data using binary-decomposed high-order entropy coding

Lossless compression of multi-dimensional medical image data...

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IEEE International Conference on Image Processing

作者： S.S. Yu M.N. Wernick N.P. Galatsanos AT and T Bell Laboratories Inc. Naperville IL USA Department of Electrical and Computer Engineering Illinois Institute of Technology Chicago IL USA

Information theory indicates that coding efficiency can be improved by utilizing high-order entropy coding (HOEC). However, serious implementation difficulties limit the practical value of HOEC for grayscale image compression. We present a new approach, called binary-decomposed (BD) high-order entropy coding, that significantly reduces the complexity of the implementation and increases the accuracy in estimating the statistical model. In this approach a grayscale image is first decomposed into a group of binary sub-images, each corresponding to one of the gray levels. When HOEC is applied to these sub-images instead of the original image, the subsequent coding is made simpler and more accurate statistically. We apply this coding technique in lossless compression of medical images and imaging data, and demonstrate that the performance advantage of this approach is significant.< >

关键词： Image coding Biomedical imaging entropy coding Medical diagnostic imaging High-resolution imaging Performance loss Decorrelation Information theory Gray-scale Positron emission tomography

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