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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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Two-Degree Vanishing Moments on 2-D Non-separable GenLOT

Two-Degree Vanishing Moments on 2-D Non-separable GenLOT

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International Symposium on Intelligent Signal Processing and Communication Systems

作者： Kobayashi, Tomoya Muramatsu, Shogo Kikuchi, Hisakazu Niigata Univ Dept Elect & Elect Engn Nishi Ku Niigata 9502181 Japan

ISBN: (纸本)9781424450152

This paper proposes a novel design method of two-dimensional (2-D) non-separable linear-phase paraunitary filter banks (LPPUFB). The two-degree vanishing moment constraint is derived for the lattice structure. In the 2 x 2-decomposition case, the authors have already derived the constraint and designed non-separable symmetric orthonormal wavelets with two-degree vanishing moments. This work extends the discussion to more general 2m(y) x 2m(x)-decomposition case and yields a method to impose the condition to the lattice structure. The constraint is imposed directly on design parameters so that both of the linear-phase and paraunitary property are structurally guaranteed. It is shown that the two-degree vanishing moment constraint reduces the number of parameters to be freely chosen and gives a smooth lowpass filter. Several design examples are shown to verify the significance of the novel constraint on the lattice structure.

关键词： picture coding DCT GenLOT Vanishing moments Non-separable transforms

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BLOCK-WISE IMPLEMENTATION OF DIRECTIONAL GENLOT

BLOCK-WISE IMPLEMENTATION OF DIRECTIONAL GENLOT

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16th IEEE International Conference on Image Processing

作者： Muramatsu, Shogo Hiki, Minoru Niigata Univ Dept Elect & Elect Engn Nishi Ku Niigata 9502181 Japan

ISBN: (纸本)9781424456536

This paper introduces block-wise implementation of 2-D nonseparable linear-phase paraunitary filter banks (LPPUFB) and shows a directional design approach. As a previous work, the authors have proposed a lattice structure of non-separable LPPUFBs which guarantees both of the linear-phase and orthogonal property. This paper shows that the structure serves variability of basis images without any violation to the orthogonality. Consequently, a boundary operation for size-limitation is yielded and compatibility with the 2-D separable block-DCT becomes possible since the lattice structure is based on the block-DCT. The main advantage of non-separable systems is its directional capability, and it is allowed to produce a directional non-separable GenLOT. Although the adaptive control of basis images is under investigation, experimental results of texture coding show prospective significance of the directional GenLOT.

关键词： Directionality picture coding DCT GenLOT Non-separable transforms

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Quality evaluation and nonuniform compression of geometrically distorted images using the quadtree distortion map

Quality evaluation and nonuniform compression of geometrical...

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6th Workshop on Nonlinear Signal and Image Processing

作者： Costa, C De Natale, FGB Granelli, F Univ Trent Dept Informat & Commun Technol DIT I-38050 Trento Italy

The paper presents an analysis of the effects of lossy compression algorithms applied to images affected by geometrical distortion. it will be shown that the encoding-decoding process results in a nonhomogeneous image degradation in the geometrically corrected image, due to the different amount of information associated to each pixel. A distortion measure named quadtree distortion map (QDM) able to quantify this aspect is proposed. Furthermore, QDM is exploited to achieve adaptive compression of geometrically distorted pictures, in order to ensure a uniform quality on the final image. Tests are performed using JPEG and JPEG2000 coding standards in order to quantitatively and qualitatively assess the performance of the proposed method.

关键词： geometrical distortion picture coding quality evaluation

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Quality evaluation and nonuniform compression of geometrically distorted images using the quadtree distortion map

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2004年第12期2004卷 1899-1911页

作者： Costa, C De Natale, FGB Granelli, F Univ Trent Dept Informat & Commun Technol DIT I-38050 Trento Italy

关键词： geometrical distortion picture coding quality evaluation

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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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Region support DCT (RS-DCT) for coding of arbitrarily shaped texture

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2002年第5期12卷 320-330页

作者： Shishikui, Y Sakaida, S NHK Japan Broadcasting Corp Setagaya Ku Tokyo 1578510 Japan

Object-based coding is a promising technique for next-generation coding. Arbitrarily shaped texture coding is the key technique for object-based coding. This paper proposes a new technique, called "Region Support DCT," for arbitrarily shaped texture coding. The method is based on conventional 2-D DCT, and has as a special feature that the decoding process is achieved by a conventional DCT process. The proposed technique outperforms other techniques and involves low complexity in the decoder.

关键词： arbitrarily shaped coding DCT object-based coding picture coding

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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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Three-layer cooperative architecture for MPEG-2 video encoder LSI

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IEICE TRANSACTIONS ON ELECTRONICS 2000年第2期E83C卷 170-178页

作者： Ikeda, M Kondo, T Nitta, K Suguri, K Yoshitome, T Minani, T Naganuma, J Ogura, T Nippon Telegraph & Tel Corp Cyber Space Labs Yokosuka Kanagawa 2390847 Japan NTT Elect Corp LSI Business Grp Ebina 2430432 Japan

This paper presents an architecture for a single-chip MPEG-2 video encoder and demonstrates its flexibility and usefulness. The architecture based on three-layer cooperation provides flexible data-transfer that improves the encoder from the standpoints of versatility, scalability, and video quality. The LSI was successfully fabricated in the 0.25-mu m four-metal CMOS process. Its small size and its low power consumption make it ideal for a wide range of applications, such as DVD recorders, PC-card encoders and HDTV encoders.

关键词： MPEG-2 video signal processing embedded system LSI hardware/software co-design picture coding

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