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A generic scheme for progressive point cloud coding

IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2008年第2期14卷 440-453页

作者： Huang, Yan Peng, Jingliang Kuo, C. -C. Jay Gopi, M. Univ Calif Irvine Dept Comp Sci Irvine CA 92697 USA Sun Yat Sen Univ Dept Comp Sci Guangzhou 510275 Peoples R China Univ So Calif Ming Hsieh Dept Elect Engn Los Angeles CA 90089 USA Univ So Calif Inst Signal & Image Proc Los Angeles CA 90089 USA

In this paper, we propose a generic point cloud encoder that provides a unified framework for compressing different attributes of point samples corresponding to 3D objects with an arbitrary topology. In the proposed scheme, the coding process is led by an iterative octree cell subdivision of the object space. At each level of subdivision, the positions of point samples are approximated by the geometry centers of all tree-front cells, whereas normals and colors are approximated by their statistical average within each of the tree-front cells. With this framework, we employ attribute-dependent encoding techniques to exploit the different characteristics of various attributes. All of these have led to a significant improvement in the rate-distortion (R-D) performance and a computational advantage over the state of the art. Furthermore, given sufficient levels of octree expansion, normal space partitioning, and resolution of color quantization, the proposed point cloud encoder can be potentially used for lossless coding of 3D point clouds.

关键词： progressive coding LOD compression octree 3D point cloud

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Adapted generalized lifting schemes for scalable lossless image coding

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SIGNAL PROCESSING 2008年第11期88卷 2790-2803页

作者： Bekkouche, Hocine Barret, Michel Oksman, Jacques SUPELEC Informat Multimodal & Signal Team F-57070 Metz France SUPELEC Signals & Elect Syst Team F-91192 Gif Sur Yvette France

Still image coding occasionally uses linear predictive coding together with multiresolution decompositions, as may be found in several papers. Those related approaches do not take into account all the information available at the decoder in the prediction stage. in this paper, we introduce an adapted generalized lifting scheme in which the predictor is built upon two filters, leading to taking advantage of all the available information. With this structure included in a multi-resolution decomposition framework, we study two kinds of adaptation based on least-squares estimation, according to different assumptions, which are either a global or a local second order stationarity of the image. The efficiency in lossless coding of these decompositions is shown on synthetic images and their performances are compared with those of well-known codecs (S + P, JPEG-LS, JPEG2000, CALIC) on actual images. Four images' families are distinguished: natural, MRI medical, satellite and textures associated with fingerprints. On natural and medical images, the performances of our codecs do not exceed those of classical codecs. Now for satellite images and textures, they present a slightly noticeable (about 0.05-0.08bpp) coding gain compared to the others that permit a progressive coding in resolution, but with a greater coding time. (C) 2008 Elsevier B.V. All rights reserved.

关键词： wavelets adapted filter banks adapted lifting scheme adaptive filtering lossless image compression still image compression progressive coding multi-resolution analysis

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Spectral coding of mesh geometry with a hierarchical set partitioning algorithm

Spectral coding of mesh geometry with a hierarchical set par...

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Conference on Visual Communications and Image Processing 2008

作者： Konur, Umut Bayazit, Ulug Ates, Hasan F. Gurgen, Fikret S. Bogazici Univ Dept Comp Engn TR-34342 Istanbul Turkey Istanbul Univ Dept Comp Engn TR-34469 Istanbul Turkey Isik Univ Dept Elect Engn TR-34980 Istanbul Turkey

ISBN: (纸本)9780819469946

We propose a progressive mesh geometry coder, which expresses geometry information in terms of spectral coefficients obtained through a transformation and codes these coefficients using a hierarchical set partitioning algorithm. The spectral transformation used is the one proposed in [10] where the spectral coefficients are obtained by projecting the mesh geometry onto an orthonormal basis determined by mesh topology. The set partitioning method that jointly codes the zeroes of these coefficients, treats the spectral coefficients for each of the three spatial coordinates with the right priority at all bit planes and realizes a truly embedded bitstream by implicit bit allocation. The experiments on common irregular meshes reveal that the distortion-rate performance of our coder is significantly superior to that of the spectral coder of [10].

关键词： spectral compression hierarchical set partitioning progressive coding mesh geometry compression.

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On the rate loss of multiresolution source codes in the Wyner-Ziv setting

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IEEE TRANSACTIONS ON INFORMATION THEORY 2006年第3期52卷 1164-1171页

作者： Feng, HY Zhao, Q Stanford Univ Dept Elect Engn Stanford CA 94305 USA Oracle Corp Redwood City CA 94065 USA

In this paper, we present upper bounds on the rate loss of the multiresolution source code in the Wyner-Ziv setting (WZ-MRSC). We define two types of rate loss, the side-information rate loss and the multiresolotion rate loss, to measure the nonsuccessive refinability. The former compares the rates achievable by a given WZ-MRSC to the corresponding minimal rates achievable by single-resolution Wyner-Ziv codes, and the latter refers to the difference between the rates achievable by a given WZ-MRSC and the minimal achievable rates by any WZ-MRSC at the same resolution. We bound these two types of rate loss from above and show that the side-information rate loss and corresponding successive refinability largely depend on the side information, while there exist small universal constant upper bounds on the multiresolution rate loss that are generally independent of the side information.

关键词： Markov chain progressive coding side information successive refinement

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Hierarchical representation and coding of 3D mesh geometry

Hierarchical representation and coding of 3D mesh geometry

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IEEE International Conference on Image Processing (ICIP 2006)

作者： Celasun, Isil Eroeksuez, Serkan Siddiqui, Rizwan A. Tekalp, A. Murat Istanbul Tech Univ Dept Elect Commun Engn TR-80626 Istanbul Turkey Koc Univ Coll Engn TR-34450 Istanbul Turkey

ISBN: (纸本)9781424404810

Hierarchical mesh representation and mesh simplification have been addressed in computer graphics for adaptive level-of-detail rendering of 3D objects. In this paper, we propose a hierarchical system suitable for progressive transmission using hierarchical 3D meshes such that each mesh level has Delaunay topology. The Delaunay topology constraint on each mesh layer not only helps to design meshes with desired geometric properties, but also enables efficient compression of the mesh data. The hierarchical compression technique is based on a nearest-neighbor ordering of mesh node points. This ordering serves to define the mesh boundary as well as a spatial prediction relation on the nodes, which is employed for differential node point location. The compression method allows progressive transmission and quality scalability.

关键词： hierarchical mesh design scalable geometry compression progressive coding

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progressive coding of stereo images using wavelets

Progressive coding of stereo images using wavelets

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Conference on Mathematics of Data/Image coding, Compression and Encryption V, with Applications

作者： Palfner, T Mali, A Müller, E Univ Rostock Inst Telecommun & Informat Technol D-18119 Rostock Germany

This paper deals with the efficient storage and transmission of stereo images. It introduces a compression algorithm based on the Discrete Wavelet Transform and an adapted SPIHT-coder. By using objective quality tests... 详细信息

ISBN: (纸本)0819445606

关键词： progressive coding stereo images Discrete Wavelet Transform

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A linear-complexity distortion optimal scheme for the transmission of packetized progressive bitstreams

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IEEE SIGNAL PROCESSING LETTERS 2005年第5期12卷 365-368页

作者： Etemadi, F Yousefi' zadeh, H Jafarkhani, H Univ Calif Irvine Dept Elect Engn & Comp Sci Irvine CA 92697 USA

We propose a novel distortion minimization technique for the transmission of a packetized progressive bitstream. The optimality of our proposed algorithm is analytically proved for a class of sources satisfying a stated condition. It is shown that Gauss-Markov sources belong to the latter class for which the algorithm is optimal. We show that our proposed optimization technique is robust and has a linear complexity in the transmission rate. Simulation results show the effectiveness of our proposed algorithm.

关键词： joint source-channel coding progressive coding rate allocation

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Content layer progressive coding of digital maps

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2002年第12期11卷 1349-1356页

作者： Forchhammer, S Jensen, OR Tech Univ Denmark Res Ctr COM 371 DK-2800 Lyngby Denmark

A new lossless context based method is presented for content progressive coding of limited bits/pixel images, such as maps, company logos, etc., common on the World Wide Web. progressive encoding is achieved by encoding the image in content layers based on color level or other predefined information. Information from already coded layers are used when coding subsequent layers. This approach is combined with efficient template based context bilevel coding, context collapsing methods for multilevel images and arithmetic coding. Relative pixel patterns are used to collapse contexts. Expressions for calculating the resulting number of contexts are given. The new methods outperform existing schemes coding digital maps and in addition provide progressive coding. Compared to the state-of-the-art PWC coder, the compressed size is reduced to 50-70% on our layered map test images.

关键词： contexts digital maps graphics image coding image communication progressive coding

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On successive refinement for the Wyner-Ziv problem

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IEEE TRANSACTIONS ON INFORMATION THEORY 2004年第8期50卷 1636-1654页

作者： Steinberg, Y Merhav, N Technion Israel Inst Technol Dept Elect Engn IL-32000 Haifa Israel

Achievable rates are characterized for successive refinement (SR) in the Wyner-Ziv scenario, namely, in the presence of correlated side information (SI) at the receivers. In this setting, the encoder is assumed to operate in two stages, where the first corresponds to relatively low rate and high distortion, and the second, comprising a refinement code on top of the first code, is aimed at reproduction at reduced distortion. Both decoders (for low rate/high distortion and for high rate/low distortion) are equipped with SI streams, correlated to the source, but unavailable to the encoder. Furthermore, it is assumed that the decoder that receives the higher rate bitstream, i.e., the additional refinement bits, accesses also SI of "better quality" than that of the lower resolution decoder. By "better quality," we mean that the source and the SI are modeled together as a stochastically degraded joint source, where the encoded symbols, the SI at the refinement stage, and the SI at the initial (coarse) stage, form a Markov chain in this order. For a memoryless joint process (that includes the source to be encoded and its instantaneously correlated SI streams), necessary and sufficient conditions are furnished, in terms of single-letter formulas, for the achievability of a pair of rates, corresponding to two given distortion levels. Special attention is devoted to the degenerate, but important, case where the two SI streams, at the two decoders, are identical. For this case, conditions are provided for successive refinability in the sense of the existence of codes that asymptotically achieve the Wyner-Ziv rate-distortion function, simultaneously at both distortion levels. In this context, the doubly symmetric binary source (with the Hamming distortion measure) and the jointly Gaussian source (with the squared error distortion measure) are successively refinable in the Wyner-Ziv setting. It is demonstrated that a source that is not successively refinable in the ordinary sens

关键词： multiple description progressive coding scalable coding side information (SI) successive refinement (SR) Wyner-Ziv problem

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JPEG2000 and dissemination of cultural heritage over the Internet

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2004年第3期13卷 293-301页

作者： Politou, EA Pavlidis, GP Chamzas, C Cultural & Educ Technol Inst Xanthi 67100 Greece

By applying the latest technologies in image compression for managing the storage of massive image data within cultural heritage databases and by exploiting the universality of the Internet we are now able not only to effectively digitize, record and preserve, but also to promote the dissemination of cultural heritage. In this work we present an application of the latest image compression standard JPEG2000 in managing and browsing image databases, focusing on the image transmission aspect rather than database management and indexing. We combine the technologies of JPEG2000 image compression with client-server socket connections and client browser plug-in, as to provide with an all-in-one package for remote browsing of JPEG2000 compressed image databases, suitable for the effective dissemination of cultural heritage.

关键词： client-server cultural image databases image compression JPEG2000 plug-ins progressive coding progressive transmission sockets

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