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DPCM picture coding USING TWO-DIMENSIONAL QUANTIZER

SIGNAL PROCESSING 1986年第3期10卷 315-322页

作者： KRISHNASAMI, P FARUQUI, MN Department of Electronics and Communication Engineering College of Engineering Jawaharlal Nehru Technological University Kakinada 533003 India Department of Electronics and Electrical Communication Engineering Indian Institute of Technology Kharagpur 721302 India

For achieving an improved performance of a DPCM coder used for encoding picture signals, it is important to design an efficient predictor and an efficient quantizer. In the DPCM coder, the improvement in SNR achieved with a 2-D predictor over a 1-D predictor is insignificant if a 1-D quantizer is used for quantizing the prediction error. This short communication describes a scheme in which a DPCM coder uses a 2-D quantizer. The performance of the scheme shows an advantage of approximately 20% savings in bandwidth over a DPCM coder using the conventional 1-D quantizer. Zusammenfassung Um das Verhalten eines DPCM-Codierers für Bildsignale zu verbessern, ist es wichtig, einen effizienten Prädiktor und einen effizienten Quantisierer zu entwerfen. Was den Codierer betrifft, ist die Verbesserung des Signal-Rauschverhältnisses bei Verwendung eines zweidimensionalen Prädiktors gegenüber dem eindimensionalen Prädiktor unbedeutend, sofern ein skalarer Quantisierer zur Quantisierung der Prädiktionsfehlers eingestzt wird. Im vorliegendem Beitrag wird eine Konfiguration vorgeschlagen, in der der DPCM-Codierer mit einem zweidimensionalen polaren Quantisierer zusammengeschaltet wird. Verglichen mit einem konventionellen skalaren Quantisierer ergibt sich ein Gewinn von 20 Prozent je Bildpunkt.

关键词： DPCM picture coding 2-D quantizer

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Rate-perceptual-distortion optimization (RpDO) based picture coding-Issues and Challenges 19

Rate-perceptual-distortion optimization (RpDO) based picture...

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19th International Conference on Digital Signal Processing (DSP)

作者： Wu, Hong Ren Lin, Weisi Ngan, King Ngi RMIT Univ Sch Elect & Comp Engn Melbourne Vic Australia Nanyang Technol Univ Sch Comp Engn Singapore 639798 Singapore Chinese Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China

ISBN: (纸本)9781479946129

Perceptual image and video coders have been reported extensively in the literature with a recent survey listing sixteen representative PVCs (perceptual video coders) for single-view video coding, ten of which conform to H. 263, MPEG-4 or H. 264/AVC international standard. Successful approaches to perceptual picture coding are classified as perceptual predictive coding, perceptual quantization, rate-perceptual-distortion optimization (RpDO) and perception-based pre-, loop-and post-filtering. This contribution analyzes and examines the performance and tradeoffs of representative perceptual as well as traditional waveform based picture coding methods in terms of their effectiveness in quality constrained coding and RpDO criterion in the context of visual quality controlled or regulated visual communication, broadcasting, entertainment and consumer electronic products, systems and services or applications. Fundamental flaws of performance benchmarking using a rate-driven coding strategy are interrogated for visual quality assured services or user experience. It is revealed that while existing perceptual distortion measures (PDMs) successfully grade distortions corresponding to HVS (human visual system) perception, their quantitative correspondence, or lack of it, to discernible levels by human visual perception in terms of just-not-noticeable-difference (JNND), just-noticeable-difference level 1 (JND1), JND level 2 (JND2), etc. has not been thoroughly investigated nor established, and this motivates the related initial work reported in this paper. Issues and constraints of existing picture coding standards are discussed in the context of developing a future picture coding standard framework for constant visual picture quality systems and services.

关键词： picture coding rate-perceptual-distortion optimization just-noticeable-difference perceptual distortion measure perceptual picture quality assessment

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picture coding employing B-spline surfaces with multiple vertices

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1997年第2期80卷 55-65页

作者： Watanabe, T Toshiba Corp Kawasaki Japan

The effect of the B-spline is that the same result as processing the generated surface is obtained only by providing the image processing to the values at the vertices of the polygon. By having the value of the point on the B-spline surface correspond to the image data and the polygon vertices generating the surface as the object of the coding, the image processing carl directly be applied to the compressed data (polygon vertices). The author and others have investigated the approximation method for the behavior of the pixel value using the B-spline surface with such an advantage. It is shown here that the same or better compression efficiency can be realized compared to the conventional DCT. Also in this paper, the method is applied to the compression coding. In this method, the multiple polygon vertices are utilized to adjust the curvature of the surface without increasing the number of vertices of the polygon to be encoded. The main purpose of the proposed method is to multiplex the polygon vertices corresponding to the rapid change of the pixel value and to improve the approximation to the pixel values by the surface. As a result of simulation, a performance surpassing the method not considering the multiple vertices is obtained, both in terms of the signal-to-noise ratio (SNR) of the restored image and the subjective assessment. In other words, it is verified that it is useful in the compression coding to introduce the multiple vertices.

关键词： picture coding information source coding B-spline surface multiple polygon vertex surface fitting

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picture coding MAKING USE OF B-SPLINE SURFACES

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1995年第7期78卷 17-29页

作者： WATANABE, T Member Research and Development Center Toshiba Corporation Kawasaki Japan 210

When the B-spline surface is used in the image representation, it suffices only to apply the image processing to the polygon vertices to derive the same result as in the processing of the whole original surface. If a compression method is established in which the points on the B-spline surface are considered as the original image data and polygon vertices are regarded as coding data, the image processing can directly be applied to the compressed data, i.e., the polygon vertices. This results in more efficient storage, transmission, and display of the image. However, no study has been made concerning the application of the B-spline to the compression coding of the surface. This paper considers the application of the B-spline with the, forementioned features to the compression coding of the image and discusses the application techniques and performances. As a result of simulation, it is seen that by adaptively determining the parameters for the surface generation and the number of polygon vertices according to the context of the image, a performance equivalent to or better than the performance of the conventional discrete cosine transform (DCT) can be realized. In other words, the B-spline surface can well be applied to the compression coding.

关键词： picture coding B-SPLINE SURFACE EDGE DETECTION SURFACE FITTING

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Rate control method for B-spline picture coding

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1997年第6期80卷 59-68页

作者： Watanabe, T Research and Development Center Toshiba Corporation Kawasaki 210 Japan Hokkaido University Department of Electronic Engineering Japan Toshiba Japan Research and Development Center Japan Stanford University United States Institute of Television Engineering IEEE Japan

As a coding algorithm in which picture processing can be applied directly to the compressed data, the author has proposed a surface-fitting method (B-spline coding) for the variation of the pixel values using the B-spine surfaces. It was shown that the performance of the new algorithm is equal to or better than the one in the DCT system, even for the compression efficiency. On the other hand, in some compression coding systems dealing with picture data, it is required that the coding is completed for one picture at a predetermined rate. Such problems of controlling the coding rate have not been studied for B-spline coding. In this paper, a method is proposed for dealing with the above problems. In addition, an effort is made to enhance the performance of B-spline surfaces as a compression tool. In this paper, the number of coded bits of each block is controlled by adaptive feedback, depending on the fineness of the picture pattern and the actual number of coded bits generated. A performance evaluation shows that the deviation of the actual number of coded bits from the specified number can be kept within 1%, while the compression performance (better than that of the DCT system) is maintained, and that coding rate control is possible in B-spline coding. (C) 1997 Scripta Technica, Inc.

关键词： picture coding B-spline surfaces surface fitting coding rate control adaptive bits assignment

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Performance improvement for picture coding making use of B-spline surfaces

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ELECTRONICS AND COMMUNICATIONS IN JAPAN PART I-COMMUNICATIONS 1998年第7期81卷 55-65页

作者： Watanabe, T Toshiba Corp Ctr Res & Dev Kawasaki Kanagawa 210 Japan

We have studied a picture coding system that can directly process compressed picture data, and have proposed a pixel value interpolation method using B-spline surfaces. We showed that its compression performance exceeds that of the conventional DCT picture coding system. A problem with this system, however, is that the coding frequency range that can yield high compression performance is limited because the applied polygon size is fixed. This paper proposes a solution to the problem, improves the performance of the proposed coding system, and uses it as a compression tool for B-spline surfaces. We propose an adaptive and automatic selection of polygon size to synthesize a surface depending on the fineness of a picture, and show a stable high compression performance for a broader range of coding frequencies. Furthermore, we study additional performance improvement achieved by increasing the kinds of polygon vertexes used, applying a weighting process to reduce coding error at block boundaries when we calculate polygon vertex value. We show the reduction of block distortions, seen at low coding frequencies in a reproduced picture. (C) 1998 Scripta Technica.

关键词： picture coding B-spline surface basis function surface interpolation block distortion

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picture coding employing B-spline surfaces with multiple vertices

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Electronics and Communications in Japan (Part I: Communications) 1998年第2期80卷

作者： Toshiaki Watanabe Research & Development Center Toshiba Corporation Kawasaki Japan 210

The effect of the B-spline is that the same result as processing the generated surface is obtained only by providing the image processing to the values at the vertices of the polygon. By having the value of the point on the B-spline surface correspond to the image data and the polygon vertices generating the surface as the object of the coding, the image processing can directly be applied to the compressed data (polygon vertices). The author and others have investigated the approximation method for the behavior of the pixel value using the B-spline surface with such an advantage. It is shown here that the same or better compression efficiency can be realized compared to the conventional DCT. Also in this paper, the method is applied to the compression coding. In this method, the multiple polygon vertices are utilized to adjust the curvature of the surface without increasing the number of vertices of the polygon to be encoded. The main purpose of the proposed method is to multiplex the polygon vertices corresponding to the rapid change of the pixel value and to improve the approximation to the pixel values by the surface. As a result of simulation, a performance surpassing the method not considering the multiple vertices is obtained, both in terms of the signal-to-noise ratio (SNR) of the restored image and the subjective assessment. In other words, it is verified that it is useful in the compression coding to introduce the multiple vertices. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80 (2):55–65, 1997

关键词： picture coding information source coding B-spline surface multiple polygon vertex surface fitting

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Rate control method for B-spline picture coding

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Electronics and Communications in Japan (Part I: Communications) 1998年第6期80卷

作者： Toshiaki Watanabe Research & Development Center Toshiba Corporation Kawasaki Japan 210

As a coding algorithm in which picture processing can be applied directly to the compressed data, the author has proposed a surface-fitting method (B-spline coding) for the variation of the pixel values using the B-spline surfaces. It was shown that the performance of the new algorithm is equal to or better than the one in the DCT system, even for the compression efficiency. On the other hand, in some compression coding systems dealing with picture data, it is required that the coding is completed for one picture at a predetermined rate. Such problems of controlling the coding rate have not been studied for B-spline coding. In this paper, a method is proposed for dealing with the above problems. In addition, an effort is made to enhance the performance of B-spline surfaces as a compression tool. In this paper, the number of coded bits of each block is controlled by adaptive feedback, depending on the fineness of the picture pattern and the actual number of coded bits generated. A performance evaluation shows that the deviation of the actual number of coded bits from the specified number can be kept within 1%, while the compression performance (better than that of the DCT system) is maintained, and that coding rate control is possible in B-spline coding. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80(6): 59–68, 1997

关键词： picture coding B-spline surfaces surface fitting coding rate control adaptive bits assignment

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ADAPTIVE PREDICTION DIFFERENTIAL PCM coding FOR TELEVISION - picture QUALITY, DATA RATE REDUCTION AND SENSITIVITY TO TRANSMISSION ERRORS

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ANNALES DES TELECOMMUNICATIONS-ANNALS OF TELECOMMUNICATIONS 1982年第7-8期37卷 299-324页

作者： KRETZ, F CCETT/Laboratoires du CNET 35013 Rennes 1266 Cedex BP France

AnalyseCet article est consacré à l’étude des algorithmes de codage d’images de télévision du type MICdifférentiel à prédiction adaptative. L’adaptativité peut jouer sur... 详细信息

Analyse Cet article est consacré à l’étude des algorithmes de codage d’images de télévision du type MICdifférentiel à prédiction adaptative. L’adaptativité peut jouer sur le prédicteur et aussi sur le quantificateur. L’auteur pose le problème et rappelle les propriétés de la source (structure des images) qui serviront de base à l’adaptativité du prédicteur. Divers algorithmes de prédiction adaptative sont décrits et certaines de leurs caractéristiques telles que l’efficacité en réduction de la dynamique de l’erreur de prédiction et la susceptibilité aux erreurs de transmission sont comparées. Une annexe traite de l’optimalisation d’un prédicteur fixe selon deux types de critère.

关键词： picture coding Transient picture Predictive coding Adaptive coding Differential PCM picture quality Data compression Transmission error Adaptive algorithm Edge

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Performances analysis of a transmission system for H263 compressed and turbo-coded video sequences over a UMTS/TDD downlink

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ANNALS OF TELECOMMUNICATIONS 2002年第11-12期57卷 1149-1170页

作者： Farah, J Marx, F Arndt, M France Telecom R&D DIH F-38243 Meylan France

The aim of this paper is to present a comparative study of the performances, in terms of the mean PSNR (Peak Signal to Noise Ratio), of a UMTS/TDD transmission system for H263 compressed and turbo-coded video sequences. Several parameters are emphasized, among them : the rate of occurrence of Intra coded frames, the video compression level and the Bit Error Rate of the transmission channel. We also present a methodology for determining the best repartition scheme of the global channel bandwidth between source and channel coding, in order to minimize the global distortion on the transmitted sequences.

关键词： mobile radiocommunication UNITS code division multiple access physical layer multipath propagation fading adaptive filtering turbo code picture coding moving image error propagation picture quality source coding channel coding

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