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Robust Image and Video Transmission Over Spectrally Shaped Channels Using Multicarrier Modulation

IEEE TRANSACTIONS ON MULTIMEDIA 1999年第1期1卷 88-103页

作者： Zheng, Haitao Liu, K. J. Ray Univ Maryland Syst Res Inst College Pk MD 20742 USA Univ Maryland Dept Elect Engn College Pk MD 20742 USA

This paper presents a new parallel transmission framework for reliable multimedia data transmission over spectrally shaped channels using multicarrier modulation. We propose to transmit source data layers of different perceptual importance in parallel, each occupying a number of subchannels. New loading algorithms are developed to efficiently allocate the available resources, e.g., transmitted power and bit rate, to the subchannels according to the source layers they transmit. Instead of making the bit error rate of all the subchannels equal as in most existing loading algorithms, the proposed algorithm assigns different error performance to the subchannels to achieve unequal error protection for different layers. The channel induced distortion in mean-square sense is minimized. We show that the proposed system can be applied nicely to both fixed length coding and variable-length coding. Asymptotic gains with respect to channel distortion are also derived. Numerical examples show that the proposed algorithm achieves significant performance improvement compared to the existing work, especially for spectrally shaped channels commonly used in in ADSL systems.

关键词： Combined source coding and channel modulation entropy coding layered coding multicarrier modulation multimedia transmission spectrally shaped channel subband coding

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A Comprehensive Study and Performance Evaluation of HDR Video coding

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ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2019年第3期44卷 2427-2444页

作者： Mir, Junaid Talagala, Dumidu S. Fernando, Anil Arachchi, Hemantha K. Univ Engn & Technol Taxila Dept Elect Engn Taxila Pakistan Univ Surrey CVSSP Guildford Surrey England

With production side for the HDR video being standardized, the distribution phase is still in its infancy. Although a number of promising HDR video coding methods exist, the standardization efforts for HDR video distribution are hampered due to limited performance evaluations. This paper addresses this shortcoming by first reviewing the existing HDR video coding methods categorically. A comprehensive performance evaluation is then presented of five state-of-the-art HDR video coding methods, namely HDR-MPEG, HDR10 (PQ), HLG HDR-TV, AdaptRes and SHVC-based coding method. The evaluation was performed on a HDR video dataset considering two HDR display configurations with four objective quality measures including HDR-VDP-2.2 and HDR-VQM quality metrics. The results reveal novel observations regarding two-layer backward-compatible HDR video coding methods indicating that these methods can provide better or similar HDR quality as in single-layer backward-compatible HDR video coding method HLG HDR-TV. Furthermore, HDR10 (PQ), the single-layer method designed for only HDR content delivery, outperforms the other evaluated methods in this work, demonstrating that best HDR quality can be achieved only without the constraint of backward compatibility. Finally, a discrepancy revealed in the performance, in terms of the HDR-VQM metric when compared to the other quality measures, is presented and its implications are discussed.

关键词： Backward compatibility HDR video coding methods HDR video compression HDR Video distribution layered coding

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Multi-Resolution Multicasting Over the Grassmann and Stiefel Manifolds

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2017年第8期16卷 5296-5310页

作者： Seddik, Karim G. Gohary, Ramy H. Hussien, Mohammad T. Shaqfeh, Mohammad Alnuweiri, Hussein Yanikomeroglu, Halim Amer Univ Cairo Elect & Commun Engn Dept New Cairo 11835 Egypt Carleton Univ Dept Syst & Comp Engn Ottawa ON K1S 5B6 Canada Alexandria Univ Dept Elect Engn Alexandria 21544 Egypt Penn State Univ Sch Elect Engn & Comp Sci University Pk PA 16802 USA Texas A&M Univ Qatar Dept Elect Engn Doha Qatar

We consider the design of space-time codes for the multiple-input multiple-output multicast communication systems with two classes of receivers. The first class comprises high-resolution (HR) receivers which have access to reliable channel state information (CSI) and can perform coherent detection, and the second class comprises low-resolution (LR) receivers which do not have access to CSI and can only perform non-coherent detection. We propose a layered encoding structure in which LR information available to both classes of receivers is encoded using Grassmannian constellations, and an incremental component, which is available only to the HR receivers, is encoded in the particular bases of the transmitted Grassmannian constellation points, thereby giving rise to constellations on the Stiefel manifold. The proposed structure enables reliable coherent communication of the HR information without compromising the reliability with which the basic LR information is non-coherently communicated. To effect rate-efficient communication of the incremental, HR layer, we use optimization methods on the Stiefel manifold to develop a novel technique for designing the unitary constellations directly. This approach alleviates the restriction imposed by the traditional techniques in which unitary space-time codes are constructed from scalar constellations. As such, this approach enables better control of the distance spectrum of the developed constellations and more effective utilization of the degrees of freedom that underlie the Stiefel manifold. For the LR receivers, we use maximum likelihood detection, whereas for the HR receivers, we develop a computationally-efficient two-step sequential detector which detects the LR information prior to detecting the incremental component superimposed on it. The detectors and the layered structure with the aforementioned constellations enable full diversity and maximum degrees of freedom to be achieved on the Grassmann and Stiefel manifolds.

关键词： Non-coherent Communications layered coding Grassmannian Codes Multicasting MIMO

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Multi-Resolution Multicasting Using Grassmannian Codes and Space Shift Keying

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2019年第1期68卷 988-992页

作者： ElMossallamy, Mohamed A. Seddik, Karim G. Gohary, Ramy H. Univ Houston Elect & Comp Engn Dept Houston TX 77004 USA Amer Univ Cairo Elect & Commun Engn Dept New Cairo 11835 Egypt Carleton Univ Dept Syst & Comp Engn Ottawa ON K1S 5B6 Canada

In this paper, we develop a novel layered coding scheme for the multiple-input multiple-output multicast channel. In this scheme, information is encoded in two layers, a base low-resolution (LR) layer and refining high-resolution (HR) one. The LR layer is encoded using Grassmannian noncoherent codes and the HR layer is encoded in the indices of the active transmitter antennas using the so-called space shift keying modulation. An efficient algorithm is proposed to optimize the HR codebook. The LR information can be detected noncoherently without invoking any channel state information (CSI), whereas the HR information must be detected coherently and, thus, requires accurate CSI. Hence, receivers with perfect CSI can decode both the LR and HR information, whereas those with no CSI can only decode the LR information. For receivers with accurate CSI, we propose a computationally efficient two-step detector and we show that the noncoherent detector performance is not affected by the transmission of the incremental HR information encoded in the transmit antenna indices.

关键词： MIMO space-time codes layered coding Grassmannian codes spatial modulation multicasting

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Ultra-Reliable Cloud Mobile Computing with Service Composition and Superposition coding 50

Ultra-Reliable Cloud Mobile Computing with Service Compositi...

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50th Annual Conference on Information Science and Systems (CISS)

作者： Azimi, Seyyed Mohammadreza Simeone, Osvaldo Sahin, Onur Popovski, Petar New Jersey Inst Technol ECE Dept CWCSPR Newark NJ USA InterDigital London England Aalborg Univ Aalborg Denmark

ISBN: (纸本)9781467394574

An emerging requirement for 5G systems is the ability to provide wireless ultra-reliable communication (URC) services with close-to-full availability for cloud-based applications. Among such applications, a prominent role is expected to be played by mobile cloud computing (MCC), that is, by the offloading of computationally intensive tasks from mobile devices to the cloud. MCC allows battery-limited devices to run sophisticated applications, such as for gaming or for the "tactile" internet. This paper proposes to apply the framework of reliable service composition to the problem of optimal task offloading in MCC over fading channels, with the aim of providing layered, or composable, services at differentiated reliability levels. Inter-layer optimization problems, encompassing offloading decisions and communication resources, are formulated and addressed by means of successive convex approximation methods. The numerical results demonstrate the energy savings that can be obtained by a joint allocation of computing and communication resources, as well as the advantages of layered coding at the physical layer and the impact of channel conditions on the offloading decisions.

关键词： Ultra-reliable communications 5G mobile cloud computing layered coding call graph application offloading

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Multilayered Wyner-Ziv Lattice coding for Single-Cell Point-to-Multipoint Communications 13

Multilayered Wyner-Ziv Lattice Coding for Single-Cell Point-...

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13th IEEE International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)

作者： Smirani, Sinda Denis, Juwendo Jouaber, Badii Telecom SudParis Inst Mines Telecom CNRS SAMOVARUMR 5157 Evry France

ISBN: (纸本)9781538638392

This paper addresses the problem of single-cell point-to-multipoint communications. We consider a base station that needs to transmit a common information to a group of users. We propose a layered Wyner-Ziv coding (WZC) scheme based on nested lattice quantization. In our scheme, we use the base layer generated by a standard coder as the decoders side information. Then, WZC is performed for quality enhancement of the transmitted message. With the proposed layered coding, multiple refinement messages will be generated. The layered messages can be decoded each by a subgroup of users based on their channel conditions. We optimize the scheme parameters in order to maximize the end-to-end multicast rate and minimize the reconstruction distortions experienced at each subgroup of users. Numerical results show that our scheme performs well when compared with the basic multicasting scheme.

关键词： layered coding Wyner-Ziv point-to-multipoint communication nested lattice codes subgrouping

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YOGA: Yet Another Geometry-based Point Cloud Compressor 23

YOGA: Yet Another Geometry-based Point Cloud Compressor

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31st ACM International Conference on Multimedia (MM)

作者： Zhang, Junteng Chen, Tong Ding, Dandan Ma, Zhan Hangzhou Normal Univ Hangzhou Peoples R China Nanjing Univ Nanjing Peoples R China

ISBN: (纸本)9798400701085

A learning-based YOGA (Yet Another Geometry-based Point Cloud Compressor) is proposed. It is flexible, allowing for the separable lossy compression of geometry and color attributes, and variable-rate coding using a single neural model;it is high-efficiency, significantly outperforming the latest G-PCC standard quantitatively and qualitatively, e.g., 25% BD-BR gains using PCQM (Point Cloud Quality Metric) as the distortion assessment, and it is lightweight, e.g., similar runtime as the G-PCC codec, owing to the use of sparse convolution and parallel entropy coding. To this end, YOGA adopts a unified end-to-end learning-based backbone for separate geometry and attribute compression. The backbone uses a two-layer structure, where the downscaled thumbnail point cloud is encoded using G-PCC at the base layer, and upon G-PCC compressed priors, multiscale sparse convolutions are stacked at the enhancement layer to effectively characterize spatial correlations to compactly represent the full-resolution sample. In addition, YOGA integrates the adaptive quantization and entropy model group to enable variable-rate control, as well as adaptive filters for better quality restoration.

关键词： Point cloud compression geometry attribute layered coding

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Improved path selection algorithms for multipath video streaming in wireless ad-hoc networks

Improved path selection algorithms for multipath video strea...

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IEEE Military Communications Conference (MILCOM 2007)

作者： Murthy, Sudheendra Hegde, Prasad Parameswaran, Viswesh Li, Baoxin Sen, Arunabha Arizona State Univ Dept Comp Sci & Engn Tempe AZ 85281 USA

ISBN: (纸本)9781424415120

In a recent paper, Wei and Zakhor [1] presented a novel multipath selection framework for streaming video over wireless ad-hoc networks. We point out some limitations of their approach and suggest techniques to overcome those limitations. We propose that different metrics for multipath computation should be used when different schemes (e.g., Multiple Description coding and layered coding) are used for video encoding. We adopt a more practical measurement technique for predicting the quality of a link. In addition to analytical reasoning for improved performance of our techniques, we conduct extensive experimentation to evaluate the efficacy of our approach. The results demonstrate that our approach leads to significantly better performance when compared to the approach proposed in [1].

关键词： mobile ad-hoc networks video transmission multiple description coding layered coding packet drop probability expected transmission count

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A Broadcast Approach to Multiple Access Adapted to the Multiuser Channel

A Broadcast Approach to Multiple Access Adapted to the Multi...

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IEEE International Symposium on Information Theory (ISIT)

作者： Kazemi, Samia Tajer, Ali Rensselaer Polytech Inst Elect Comp & Syst Engn Dept Troy NY 12180 USA

ISBN: (纸本)9781509040964

A broadcast strategy for multiple access communication over slowly fading channels is introduced, in which the channel state information is known to only the receiver. In this strategy, the transmitters split their information streams into multiple independent information layers, each adapted to a specific actual channel realization. The major distinction between the proposed strategy and the existing ones is that in the existing approaches, each transmitter adapts its transmission strategy only to the fading process of its direct channel to the receiver, hence directly adopting a single-user strategy previously designed for the single-user channels. However, the contribution of each user to a network-wide measure (e.g., sum-rate capacity) depends not only on the user's direct channel to the receiver, but also on the qualities of other channels. Driven by this premise, this paper proposes an alternative broadcast strategy in which the transmitters adapt their transmissions to the combined states resulting from all users' channels. This leads to generating a larger number of information layers by each transmitter and adopting a different decoding strategy by the receiver. An achievable rate region that captures the trade-off among the rates of different information is established and is shown to subsume the existing known regions.

关键词： Broadcast approach fading channel layered coding multiple access successive decoding

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Referential loss recovery for streaming audio using application level multicast

Referential loss recovery for streaming audio using applicat...

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11th Asia-Pacific Conference on Communications

作者： Hayasaka, M Gamage, M Miki, T Univ Electrocommun Dept Elect Engn Chofu Tokyo 1828585 Japan

ISBN: (纸本)0780391322

The demand for real-time multimedia streaming services using application level multicast (ALM) is expected to grow rapidly in the near future and these multimedia applications will consist of many media. Especially, the audio media requires a guaranteed Quality of Service (QoS). The ALM is expected to provide multicast services in a wide area. However, packet losses during transmission are a serious problem in these services as they result in degradation of the QoS. Forward Error Correction (FEC) is a promising technique to recover the lost packets and improve the QoS of streaming media. In the conventional audio streaming, pre-buffering of media stream and FEC techniques are required to cope with delay jitter and packet losses. However, FEC may degrade the QoS of all communications due to the increased congestion caused by FEC overhead with the increase of streaming sessions. In this paper, a novel FEC method that improves QoS of audio streaming services is proposed. It avoids the increased congestion caused by FEC overhead during media streaming. It also accommodates the delay jitter even without prebuffering of media stream. Furthermore, it provides the QoS according to requirements and environments of users, and location in the multicast tree by using layered coding of FEC. Thus, packet losses and jitter are recovered at each end host using ALM and do not affect the next-hop streaming. The results of computer simulations show that our proposed method provides better audio quality compared to conventional method.

关键词： audio streaming application level multicast FEC layered coding play out ratio of primary audio

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