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Optimal coding of multilayer and multiversion video streams

IEEE TRANSACTIONS ON MULTIMEDIA 2008年第1期10卷 121-131页

作者： Hsu, Cheng-Hsin Hefeeda, Mohamed Simon Fraser Univ Sch Comp Sci Surrey BC V3T 0A3 Canada

Traditional video servers partially cope with heterogeneous client populations by maintaining a few versions of the same stream with different bit rates. More recent video servers leverage multilayer scalable coding techniques to customize the quality for individual clients. In both cases, heuristic, error-prone, techniques are currently used by administrators to determine either the rate of each stream version, or the granularity and rate of each layer in a multilayer scalable stream. In this paper, we propose an algorithm to determine the optimal rate and encoding granularity of each layer in a scalable video stream that maximizes a system-defined utility function for a given client distribution. The proposed algorithm can be used to compute the optimal rates of multiversion streams as well. Our algorithm is general in the sense that it can employ arbitrary utility functions for clients. We implement our algorithm and verify its optimality, and we show how various structuring of scalable video streams affect the client utilities. To demonstrate the generality of our algorithm, we consider three utility functions in our experiments. These utility functions model various aspects of streaming systems, including the effective rate received by clients, the mismatch between client bandwidth and received stream rate, and the client-perceived quality in terms of PSNR. We compare our algorithm against a heuristic algorithm that has been used before in the literature, and we show that our algorithm outperforms it in all cases.

关键词： multimedia communication scalable coding video quality optimization video streaming

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R-D optimized progressive compression of 3D meshes using prioritized gate selection and curvature prediction

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VISUAL COMPUTER 2011年第6-8期27卷 769-779页

作者： Ahn, Jae-Kyun Lee, Dae-Youn Ahn, Minsu Kim, Chang-Su Korea Univ Sch Elect Engn Seoul South Korea Samsung Adv Inst Technol Yongin Kyunggi Do South Korea

A rate-distortion (R-D) optimized progressive coding algorithm for three-dimensional (3D) meshes is proposed in this work. We propose the prioritized gate selection and the curvature prediction to improve the connectivity and geometry compression performance, respectively. Furthermore, based on the bit plane coding, we develop a progressive transmission method, which improves the qualities of intermediate meshes as well as that of the fully reconstructed mesh, and extend it to the view-dependent transmission method. Experiments on various 3D mesh models show that the proposed algorithm provides significantly better compression performance than the conventional algorithms, while supporting progressive reconstruction efficiently.

关键词： Triangular mesh Data compression 3D mesh coding scalable coding Progressive transmission View-dependent transmission

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Adaptive representation of dynamic 3D meshes for low-latency applications

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COMPUTER AIDED GEOMETRIC DESIGN 2019年 73卷 70-85页

作者： Arvanitis, Gerasimos Lalos, Aris S. Moustakas, Konstantinos Univ Patras Elect & Comp Engn Patras Greece ATHENA Res Ctr Ind Syst Inst Maroussi Greece

Recently, 3D visual representations of highly deformable 3D models, such as dynamic 3D meshes, are becoming popular due to their capability to represent realistically the motion of real-world objects/humans, paving the road for new and more advanced immersive virtual, augmented and mixed reality experiences. However, the real-time streaming of such models introduces increasing challenges related to low cost, low-latency and scalable coding of the acquired information. In view of this, this article proposes an efficient scalable coding mechanism, that decomposes a mesh sequence into spatial and temporal layers that remove a single vertex at each layer. The removed vertices are predicted by performing Laplacian interpolation of the motion vectors. The artifacts that are introduced in low-resolution representations are mitigated using a subspace based normal-vector denoising procedure, that is optimized to support low-latency streaming scenarios using incremental SVD. A novel initialization strategy offers robustness to outliers generated due to local deformations. An extensive evaluation study using several synthetic and scanned dynamic 3D meshes highlights the benefits of the proposed approach in terms of both execution time and reconstruction quality even in very low throughput scenarios of bit-per-vertex-per-frame (bpvf). (C) 2019 Elsevier B.V. All rights reserved.

关键词： Robust PCA Incremental SVD Laplacian interpolation scalable coding

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COMPRESSION OF 10-BIT VIDEO USING THE TOOLS OF MPEG-2

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SIGNAL PROCESSING-IMAGE COMMUNICATION 1995年第1期7卷 27-56页

作者： ERDEM, AT SEZAN, MI Imaging Research and Advanced Development Eastman Kodak Company 1700 Dewey Avenue MC/01816 Rochester NY 14650 USA

We address the problem of compressing 10-bits per pixel video using the tools of the emerging MPEG-2 standard, which is primarily targeted to 8-bits per pixel video. We show that an amplitude scalable compression scheme for 10-bit video can be developed using the MPEG-2 syntax and tools. We experimentally evaluate the performance of the scalable approach and compare it with the straightforward non-scalable approach where the 10-bit input is rounded to 8 bits and usual 8-bit MPEG-2 compression is applied. In addition to general performance evaluation of scalable and non-scalable approaches, we also evaluate their multi-generation characteristics where the input video undergoes successive compression-decompression cycles. We show that it is possible to quantitatively analyze the multi-generation characteristics of the non-scalable approach using the theory of generalized projections.

关键词： VIDEO COMPRESSION scalable coding 10-BIT VIDEO MULTI-GENERATIONS GENERATION LOSS MPEG

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Layered video coding based on displaced frame difference prediction and multiresolution block matching

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IEEE TRANSACTIONS ON COMMUNICATIONS 2004年第9期52卷 1504-1513页

作者： Hwang, WJ Chen, JF Huang, YC Tsai, TY Natl Taiwan Normal Univ Grad Inst Comp Sci & Informat Engn Taipei 11676 Taiwan Acad Sinica Inst Sci Informat Taipei 115 Taiwan ALi Corp Taipei 114 Taiwan Elan Microelect Corp Hsinchu Taiwan

This paper presents a new video-coding technique based on displaced frame difference (DFD) prediction and multiresolution block matching for layered transmission. Starting from the base layer, the algorithm encodes one layer at a time until the design of the top layer is completed. For the encoding of each layer, the DFD prediction and multistage motion-vector quantization (MSMVQ) techniques are employed so that the results of DFD encoding and block matching at previous layers can be used to enhance the coding efficiency at that layer. Numerical results show that the algorithm is effective for the applications where high rate-distortion performance and low computational complexity for layered video transmission are required.

关键词： block matching scalable coding video coding

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scalable POINT CLOUD GEOMETRY coding WITH BINARY TREE EMBEDDED QUADTREE

SCALABLE POINT CLOUD GEOMETRY CODING WITH BINARY TREE EMBEDD...

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IEEE International Conference on Multimedia and Expo

作者： Birendra Kathariya Li Li Zhu Li Jose Alvarez Jianle Chen University of Missouri-Kansas City Futurewei Technologies Inc.

Many applications of point cloud have recently been identified in automobile navigation system, visual communication, and so on. However, the huge data size of point cloud has been a bottleneck for the practical implementations. In this paper, we present a compression scheme that utilizes variable-rate coding of a same point cloud data at different quality. Point cloud is encoded at fixed-rate for highest representation. Encoder, however, can present variable-rate encoded data for any lowest to highest representation to decoder which is then decoded to reconstruct point cloud at different quality. Variable-rate encoding is achieved through the so-called binary tree quadtree (BTQT) scheme. The BTQT scheme made the compression more effective by dividing point cloud frame into blocks using binary-tree and encoding flat surfaces in the blocks by quadtree and non-flat surfaces by octree. Simulation results show that scalable coding solution can efficiently compress point cloud data at variable rate compensating the quality.

关键词： Binary-tree scalable coding Octree Quadtree Point cloud

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A simple framework for spatio-temporal video segmentation and delayering using dense motion fields

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IEEE SIGNAL PROCESSING LETTERS 2006年第7期13卷 421-424页

作者： Piroddi, R Vlachos, T Univ London Imperial Coll Sci & Technol Dept Elect & Elect Engn Commun & Signal Proc Grp London SW7 2AZ England Univ Surrey Sch Elect & Phys Sci Ctr Vis Speech & Signal Proc Guildford GU2 7XH Surrey England

To represent object movement, the conventional approach is to embed the motion information into parametric and/or statistical motion models. However, the inherent complexity of this description is ill suited for application requiring rapid and automatic, albeit significant, responses. Surveillance applications belong to this class and are emerging as the most active field of research in computer vision. For this purpose, we observe that the differential invariants obtained by dense optic flow are capable of accurately describing complex object motion without requiring setting up and initializing models. In this letter, we demonstrate the novel use of. such motion descriptors for spatio-temporal object segmentation and delayering of sequences. Our results show the ability of this approach to describe simply and accurately differently moving objects and to be incorporated in segmentation processes that deliver a hierarchical description of object, producing evident improvements to the segmented objects while being computationally efficient.

关键词： motion segmentation optic flow scalable coding video processing

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Multiple-Stations scalable Transmission With Compressed Sensing for Near-Space Communication

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IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2016年 15卷 382-385页

作者： Shi, Guangming Shen, Fangfang Niu, Yi Zhao, Guanghui Lin, Jie Xidian Univ Sch Elect Engn Xian 710071 Peoples R China

Near-space communication suffers from communication blackout, which reduces the communication quality. To solve this problem, an efficient Multiple-Stations scalable Transmission scheme based on compressed sensing theory is proposed. The proposed scheme exhibits two advantages. First, multiple-station receivers are disposed at different locations to accomplish continuous and real-time communication with the hypersonic vehicle. Second, by utilizing the democracy and scalability of the CS, a scalable CS-based coding method is developed in which a two-layer structure is adopted to improve the coding efficiency. Finally, simulation results show that the proposed scheme can achieve a reliable communication in the presence of data loss caused by communication interruption.

关键词： Communication compressed sensing scalable coding

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Rethinking Semantic Image Compression: scalable Representation With Cross-Modality Transfer

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2023年第8期33卷 4441-4445页

作者： Zhang, Pingping Wang, Shiqi Wang, Meng Li, Jiguo Wang, Xu Kwong, Sam City Univ Hong Kong Dept Comp Sci Hong Kong Peoples R China City Univ Hong Kong Shenzhen Res Inst Shenzhen 518057 Peoples R China Univ Chinese Acad Sci Inst Comp Technol Beijing 100049 Peoples R China Shenzhen Univ Coll Comp Sci & Software Engn Shenzhen 518060 Peoples R China Shenzhen Univ Guangdong Lab Artificial Intelligence & Digital Ec Shenzhen 518060 Peoples R China

This article proposes the scalable cross-modality compression (SCMC) paradigm, in which the image compression problem is further cast into a representation task by hierarchically sketching the image with different modalities. Herein, we adopt the conceptual organization philosophy to model the overwhelmingly complicated visual patterns, based upon the semantic, structure, and signal level representation accounting for different tasks. The SCMC paradigm that incorporates the representation at different granularities supports diverse application scenarios, such as high-level semantic communication and low-level image reconstruction. The decoder, which enables the recovery of the visual information, benefits from the scalable coding based upon the semantic, structure, and signal layers. Qualitative and quantitative results demonstrate that the SCMC can convey accurate semantic and perceptual information of images, especially at low bitrates, and promising rate-distortion performance has been achieved compared to state-of-the-art methods. The code will be available online https://***/ppingzhang/SCMC.

关键词： Semantic image compression cross-modality scalable 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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