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A Novel Hierarchical Decomposition Vector Quantization Method for High-Order LPC Parameters

IEEE-ACM TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2015年第1期23卷 212-221页

作者： Wang, Lin Chen, Zhe Yin, Fuliang Dalian Univ Technol Sch Elect & Informat Engn Dalian 116023 Peoples R China Queen Mary Univ London Sch Elect Engn & Comp Sci London E1 4NS England

The paper investigates vector quantization coding of high-order (e. g., 20th-50th order) linear prediction coding (LPC) parameters, and proposes a novel hierarchical decomposition vector quantization method for a scalable speech coding framework with variable orders of LPC analysis. Instead of vector quantizing the whole group of LPC parameters in the linear spectral frequency (LSF) domain directly, the proposed method decomposes the high-order LPC model into several low-order (e. g., 10th-order) LPC models, and vector quantizes them in the LSF domain separately. For the decomposition, the high-order LPC model is converted into a group of reflection coefficients at first, and then the group is split into several subgroups and converted into multiple low-order LPC models. It is shown that the proposed method is naturally suitable for a scalable coding framework where the information of the decomposed low-order LPC models can be encoded into a multi-layered bitstream and can be combined in a progressive way to recover the high-order LPC information. Experiments in a scalable coding framework with variable LPC analysis orders (10-50) reveal that, compared to a direct vector quantization scheme, the proposed method can reduce the size of the codebook and the number of coding bits significantly, and can also efficiently reduce the computation cost.

关键词： Line spectral frequency linear prediction coding (LPC) reflection coefficient scalable coding vector quantization

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Disk-based storage for scalable video

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1997年第5期7卷 758-770页

作者： Chang, E Zakhor, A UNIV CALIF BERKELEY BERKELEYCA 94720

In this paper, we consider the placement of scalable video data on single and multiple disks for storage and realtime retrieval, For the single-disk case, we extend the principle of constant frame grouping from constant bit rate (CBR) to variable bit rate (VBR) scalable video data. When the number of admitted users exceeds the server capacity, the rate of data sent to each user is reduced to relieve the disk system overload, offering a graceful degradation in comparison with nonscalable data, We examine the qualities of video reconstructions obtained from a real disk video server and find the scalable video more visually appealing. In the VBR case, scalability is also used to improve interactivity by reducing the delay associated with using interactive functions in a predictive admission control environment. Finally, we consider the multiple disk scenario and prove that periodic interleaving results in lo,ver system delay than striping in a video server using round-robin scheduling. We verify the results through detailed simulation of a four-disk array.

关键词： data storage hard disk scalable coding server video

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Color LAR codec:: A color image representation and compression scheme based on local resolution adjustment and self-extracting region representation

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2007年第8期17卷 974-987页

作者： Deforges, Olivier Babel, Marie Bedat, Laurent Ronsin, Joseph INSA Rennes IETR Image Grp F-35043 Rennes France

We present an efficient content-based image coding called Locally Adaptive Resolution (LAR) offering advanced scalability at different semantic levels, i.e., pixel, block, and region. A local analysis of image activity leads to a nonuniform block representation supporting two layers of image description. The first layer provides global information encoded in the spatial domain enabling a low bit rate while preserving contours. The second layer holds texture information encoded in the spectral domain, enabling scalable bitstream in accordance with the required quality. This basic LAR coding leads to an efficient progressive compression, evaluated through subjective quality tests. Its nonuniform block representation also allows a hierarchical region representation providing higher semantic functionalities. More precisely, the segmentation process can be simultaneously performed at both the coder and the decoder from only the luminance component highly compressed by the first coding layer. This solution provides a representation at a region level while avoiding any contour encoding overhead. Region enhancement can then be realized through the second layer. Furthermore, very high compression of the chromatic components is achieved thanks to this region representation. In this scheme, a low-cost chromatic control, which was first introduced during the segmentation process, increases the consistency of region representation in terms of color.

关键词： gray-level and color images segmentation region-of-interest coding region representation-based coding scalable coding

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Hierarchical 2-D mesh representation, tracking, and compression for object-based video

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1999年第2期9卷 353-369页

作者： van Beek, P Tekalp, AM Zhuang, N Celasun, I Xia, MH Univ Rochester Dept Elect Engn Rochester NY 14627 USA Univ Rochester Ctr Elect Imaging Syst Rochester NY 14627 USA

This paper proposes methods for designing, tracking and coding hierarchical two-dimensional (2-D) content-based mesh representations. The design procedure consists of constructing a fine-to-coarse hierarchy of Delaunay meshes, using image- and shape-based criteria for mesh geometry simplification. Hierarchical tracking employs a coarse-to-fine strategy with mesh-based motion vector optimization, We introduce new techniques to maintain the initial mesh hierarchy and topology during tracking by imposing certain constraints at each stage of the procedure, The hierarchical compression technique is based on a nearest neighbor ordering of mesh node points. This ordering serves to identify the mesh boundary nodes as well as establish spatial predictors for differential coding of node coordinates and motion vectors, The proposed hierarchical mesh representation, which has applications in object-based video manipulation, indexing, and compression, provides improved tracking performance (compared to a nonhierarchical representation) and allows progressive (scalable) transmission of the object geometry (including shape) and motion information, as well as variable level-of-detail rendering, Experimental results are presented to compare the tracking and compression performance of hierarchical versus nonhierarchical mesh representations and to demonstrate the tradeoff between image quality and mesh bit rate for 2-D mesh-based video object rendering.

关键词： hierarchical mesh model hierarchical motion tracking multimedia coding object-based video scalable coding

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scalable, error-resilient, and high-performance video communications in mobile wireless environments

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2001年第7期11卷 833-847页

作者： Vass, J Zhuang, S Zhuang, XH Eyeball Networks Inc Vancouver BC V7T 1A2 Canada Univ Calif Berkeley Dept Elect Engn & Comp Sci Berkeley CA 94720 USA Univ Missouri Dept Comp Engn & Comp Sci Columbia MO 65211 USA

A novel mobile communications system is proposed in the paper, which provides not only effective but also efficient video access for mobile users when communicating over low-bandwidth error-prone wireless links, The middleware implemented by a mobile proxy server at the mobile support station is designed for the seamless integration of mobile users with video servers, so the specific details of the underlying protocols and source/channel coding techniques are hidden to both the video server and mobile client. Based on the concept of application-level framing, the application (video codec in our case) plays a significant role in network communications that most of functionalities of the system are implemented as part of the application, As such, at the application layer, adaptive source- and channel-coding techniques are developed to jointly provide the user with the highest possible video quality, For efficient source coding, our high-performance low-complexity video-coding algorithm called a 3-D significance-linked connected component analysis (3D-SLCCA) is chosen, Due to its high robustness against channel-error propagation, 3D-SLCCA is well suited for wireless environments. For error-resilient channel coding, a multilayer transmission error-control mechanism is developed, Since there is no additional requirement imposed on either the mobile client or the video server, mobile users interact with the server in exactly the same way as stationary users, Extensive computer experiments demonstrate the effectiveness of the proposed system.

关键词： error-resilient coding joint source-channel coding mobile communications proxy server scalable coding SLCCA video coding

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Progressive watermarking techniques using genetic algorithms

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CIRCUITS SYSTEMS AND SIGNAL PROCESSING 2007年第5期26卷 671-687页

作者： Huang, Hsiang-Cheh Pan, Jeng-Shyang Huang, Yu-Hsiu Wang, Feng-Hsing Huang, Kuang-Chih Natl Univ Kaohsiung Kaohsiung 811 Taiwan Natl Kaohsiung Univ Appl Sci Kaohsiung 807 Taiwan Cheng Shiiu Univ Kaohsiung 833 Taiwan

An innovative watermarking scheme based on progressive transmission with genetic algorithms (GAS) is proposed. We implement the watermarking embedding and extraction systems in the transform domain, and apply the JPEG spectral selection mode for scalable transmission of the watermarked image. By employing a GA with a proper fitness function into the watermarking system, both the watermark imperceptibility and watermark robustness requirements are considered and optimized. The number of embedded bits, or the watermark capacity, is much larger than that in other existing algorithms in the literature. Also, the watermark capacity in the proposed algorithm lies within the theoretical limit. In addition, the embedded watermark can be partly extracted at the receiver side even when the watermarked image is being transmitted. Simulation results show both the robustness and the effectiveness of progressive transmission under different attacking schemes and different bandwidth variations. The proposed scheme is directly applicable to scalable coding of multimedia, such as MPEG-4 scalable video coding.

关键词： watermarking JPEG scalable coding progressive transmission optimization genetic algorithms

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A Context-Aware Network Equipment for Dynamic Adaptation of Multimedia Services in Wireless Networks

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WIRELESS PERSONAL COMMUNICATIONS 2009年第1期48卷 69-92页

作者： Mathieu, Bertrand France Telecom R&D F-22307 Lannion France

B3G (Beyond 3rd Generation) networks is the next step in the wireless world. It will enable the delivery of services to end-users, on different underlying wireless access networks and customised to users' context. Furthermore, seamless mobility between networks and switch of devices will be handled in a transparent way. In this paper, a Context-Aware Network Equipment (CANE) is introduced, that is able to dynamically adapt multimedia services according to the users' context. The term context includes the users' device, the users' preferences, the network conditions as well as the service provider adaptation policies. As a proof of concept, an implementation of a CANE is given for a 802.11 network use-case. An evaluation of the prototype as well as simulations of the proposed solution, both for an audio streaming service and a video streaming service, are presented. The results show that adapting multimedia services in case of network overload can enable to maintain an acceptable quality of service delivered to end-users and even to allow more users to enjoy the services, which will not be possible without the CANE.

关键词： Context-awareness Dynamic adaptation of services scalable coding Programmable network equipment 802 11 networks

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Light Field coding Using Weighted Binary Images

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2019年第11期E102D卷 2110-2119页

作者： Komatsu, Koji Isechi, Kohei Takahashi, Keita Fujii, Toshiaki Nagoya Univ Grad Sch Engn Dept Informat & Commun Engn Nagoya Aichi 4648603 Japan

We propose an efficient coding scheme for a dense light field, i.e., a set of multi-viewpoint images taken with very small viewpoint intervals. The key idea behind our proposal is that a light field is represented using only weighted binary images, where several binary images and corresponding weight values are chosen so as to optimally approximate the light field. The proposed coding scheme is completely different from those of modern image/video coding standards that involve more complex procedures such as intra/inter-frame prediction and transforms. One advantage of our method is the extreme simplicity of the decoding process, which will lead to a faster and less power-hungry decoder than those of the standard codecs. Another useful aspect of our proposal is that our coding method can be made scalable, where the accuracy of the decoded light field is improved in a progressive manner as we use more encoded information. Thanks to the divide-and-conquer strategy adopted for the scalable coding, we can also substantially reduce the computational complexity of the encoding process. Although our method is still in the early research phase, experimental results demonstrated that it achieves reasonable rate-distortion performances compared with those of the standard video codecs.

关键词： light-field scalable coding

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Streaming of scalable h.264 videos over the Internet

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MULTIMEDIA TOOLS AND APPLICATIONS 2008年第3期36卷 303-324页

作者： Kantarci, Aylin Ege Univ Dept Comp Engn TR-35100 Izmir Turkey

To investigate the benefits of scalable codecs in the case of rate adaptation problem, a streaming system for scalable H.264 videos has been implemented. The system considers congestion level in the network and buffer status at the client during adaptation process. The rate adaptation algorithm is content adaptive. It selects an appropriate substream from the video file by taking into account the motion dynamics of video. The performance of the system has been tested under congestion-free and congestion scenarios. The performance results indicate that the system reacts to congestion properly and can be used for Internet video streaming where losses occur unpredictably.

关键词： scalable coding H.264/AVC content-aware streaming rate adaptation QoS management

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A wavelet video coding algorithm with balanced significance probability tree based on energy weighting

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MULTIMEDIA TOOLS AND APPLICATIONS 2019年第21期78卷 30877-30893页

作者： Song, Chuan-Ming Fu, Bo Wang, Xiang-Hai Fu, Ming-Zhe Liaoning Normal Univ Sch Comp & Informat Technol Dalian 116029 Peoples R China Dalian Univ Technol Sch Comp Sci & Technol Dalian 116024 Peoples R China Nanjing Univ State Key Lab Novel Software Technol Nanjing 210093 Jiangsu Peoples R China

This work presents a 3-D wavelet video coding algorithm. By analyzing the contribution of each biorthogonal wavelet basis to reconstructed signal's energy, we weight each wavelet subband according to its basis energy. Based on distribution of weighted coefficients, we further discuss a 3-D wavelet tree structure named balanced significance probability tree, which places the coefficients with similar probabilities of being significant on the same layer. It is implemented by using hybrid spatial orientation tree and temporal-domain block tree. Subsequently, a novel 3-D wavelet video coding algorithm is proposed based on the energy-weighted balanced significance probability tree. Experimental results illustrate that our algorithm always achieves good reconstruction quality for different classes of video sequences. Compared with asymmetric 3-D orientation tree, the average peak signal-to-noise ratio (PSNR) gain of our algorithm are 1.24dB, 2.54dB and 2.57dB for luminance (Y) and chrominance (U,V) components, respectively. Compared with temporal-spatial orientation tree algorithm, our algorithm gains 0.38dB, 2.92dB and 2.39dB higher PSNR separately for Y, U, and V components. In addition, the proposed algorithm requires lower computation cost than those of the above two algorithms.

关键词： Video coding scalable coding 3-D wavelet transform Weighted tree Significant coefficient

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