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15th IEEE International Conference on Communication Technology (ICCT)

作者： Chang, Shih-Ying Chiao, Hsin-Ta Ind Technol Res Inst Informat & Commun Res Labs Hsinchu Taiwan

ISBN: (纸本)9781479900749

Several studies indicate that video contents will be the vast majority of Internet traffic in the near future. To facilitate the distribution of video contents, we have to overcome the issue of interoperability between various servers and devices. MPEG-DASH standard is developed to provide standardized manifest format, content format and streaming protocol for adaptive streaming, thereby increasing interoperability. However, MPEG-DASH contents are delivered by HTTP without supporting data multicast. Since delivering video contents over multicast channels is necessary or useful for some applications, the authors survey the studies of delivering MPEG-DASH contents over multicast channels. It is found that few studies discuss the detailed construction of such a mechanism. This paper proposes three methods enabling the delivery of MPEG-DASH contents over multicast are proposed. And also evaluates the performance of the proposed methods over real WiFi networks. The result shows that each method has its own advantages and therefore suitable for different applications.

关键词： Streaming Forward error correction multiple description coding MPEG-DASH Multicast

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On the Role of Common Codewords in Quadratic Gaussian multiple descriptions coding

On the Role of Common Codewords in Quadratic Gaussian Multip...

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IEEE International Symposium on Information Theory (ISIT)

作者： Viswanatha, Kumar Akyol, Emrah Rose, Kenneth Univ Calif Santa Barbara ECE Dept Santa Barbara CA 93106 USA

ISBN: (纸本)9781479904464

This paper focuses on the problem of L-channel quadratic Gaussian multiple description (MD) coding. We recently introduced a new encoding scheme in [1] for general L-channel MD problem, based on a technique called 'Combinatorial Message Sharing' (CMS), where every subset of the descriptions shares a distinct common message. The new achievable region subsumes the most well known region for the general problem, due to Venkataramani, Kramer and Goyal (VKG) [2]. Moreover, we showed in [3] that the new scheme provides a strict improvement of the achievable region for any source and distortion measures for which some 2-description subset is such that the Zhang and Berger (ZB) scheme achieves points outside the El-Gamal and Cover (EC) region. In this paper, we show a more surprising result: CMS outperforms VKG for a general class of sources and distortion measures, which includes scenarios where for all 2-description subsets, the ZB and EC regions coincide. In particular, we show that CMS strictly extends VKG region, for the L-channel quadratic Gaussian MD problem for all L >= 3, despite the fact that the EC region is complete for the corresponding 2-descriptions problem. Using the encoding principles derived, we show that the CMS scheme achieves the complete rate-distortion region for several asymmetric cross-sections of the L-channel quadratic Gaussian MD problem, which have not been considered earlier.

关键词： multiple description coding Combinatorial message sharing Quadratic Gaussian multiple descriptions

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Content-Aware Video Transmission in HEVC Context: Optimization of compression, of error resilience and concealment, and of visual quality

Content-Aware Video Transmission in HEVC Context: Optimizati...

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作者： Ahmed Aldahdooh Universite Bretagne Loire

学位级别：博士

In this work, the global/local content characteristics are utilized in order to improve the delivery chain of the video sequences. The work is divided into four main parts that take advantages of video content features. The first part introduces a joint content-complexity encoder parameters prediction model. This model uses bitrate, distortion, and complexity of different parameters configurations in order to get the recommended encoder parameters value. Then, the links between content features and the recommended values are identified. Finally, the prediction model is built using these features and the recommended encoder parameter values. The second part illustrates the proposed multiple description coding (MDC) scheme that is optimized for high-order MDC. The corresponding decoding and content-dependent error recovery procedures are also identified. The quality of the received videos is evaluated subjectively. By analyzing the subjective experiment results, an adaptive, i. e. content-aware, scheme is introduced. Finally, an application scenario is simulated to study the realistic bitrate consumption. The third part uses the motion properties of a content to introduce a motion map that will be used as an input for the modified state-of-the-art inpainting based error concealment algorithm. A subjective experiment was conducted to evaluate the algorithm and also to study the content-aware observer's disturbance when perceiving the processed videos. The fourth part has two sub-parts, the first one is about HRC selection algorithms for the large-scale video database with an improved performance evaluation measures for video quality assessment algorithms using training and validation sets. The second part introduces global content aware no-reference video quality assessment.

关键词： Visual content characteristics Error resilience Error Concealment multiple description coding Video compression Visual quality assessment Video transmission HEVC standard

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Coded Wireless Video Broadcast/Multicast

Coded Wireless Video Broadcast/Multicast

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作者： She, James University of Waterloo

学位级别：master

Advancements in video coding, compact media display, and communication devices, particularly in emerging broadband wireless access networks, have created many foreseeable and exciting applications of video broadcast/multicast over the wireless meidum. For efficient and robust wireless video broadcast/multicast under fading, this thesis presents and examines a novel cross-layer framework that exploits the interplay between applying protections on a successively refinable video source and transmitting through a layered broadcast/multicast channel. The framework is realistically achieved and evaluated by using multiple description coding (MDC) on a scalable video source and using superposition coding (SPC) for layered broadcast/multicast transmissions. An analytical model using the total received/recovered video bitstreams from each coded wireless broadcast/multicast signal is developed, which serves as a metric of video quality for the system analysis and optimization. An efficient methodology has demonstrated that optimal power allocations and modulation selections can be practically determined to improve the broadcast/multicast video quality. From the information-theoretical perspective, a general closed-form formula is derived for the end-to-end distortion analysis of the proposed framework, which is applicable to any (n, k) protection code applied on a successive refinable source with a Gaussian distribution over layered Gaussian broadcast channels. The results reveal the scenarios for the proposed framework to lead to a lower distortion than a legacy system without any protection. By analyzing the characteristics of the closed-form formula, an efficient O(n log n) algorithm is developed to determine optimal k values in the (n, k) protection codes that minimize the distortion under the framework. Finally, a cross-layer design of logical SPC modulation is introduced to achieve layered broadcast/multicast for scalable video. It serves as an alternative for practical

关键词： wireless video broadcast/multicast cross-layer design successive refinement gaussian broadcast channel multiple description coding protection

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Optimal Power Allocation for a Successive Refinable Source with multiple descriptions over a Fading Relay Channel Using Broadcast/Multicast Strategies

Optimal Power Allocation for a Successive Refinable Source w...

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作者： Shi, Kun University of Waterloo

学位级别：master

In a wireless fading relay system with multicast/broadcast transmission, one of the most crucial challenges is the optimization of a transmission rate under multiuser channel diversity. Previously reported solutions for mitigating the vicious effect due to multi-user channel diversity have been mainly based on superposition coded multicast, where an optimal power allocation to each layer of modulated signals is determined. Many previous studies investigated a harmonic interplay between the successively re nable (SR) content source and a layered modulation via superposition coding (SPC) over the multicast/broadcast channels. By jointly considering the successive re nement characteristic at the source and the dependency of the layered modulation at the channel, a graceful fexibility can be achieved on a group of users with di erent channel realizations. Here most of the receivers are supposed to obtain the base quality layer information modulated in a lower rate, while the receivers with better channel realizations will obtain more information by re ning the base quality layer information using the enhancement quality layer information. In particular, the optimal power allocation for a SR source over a fading relay channel using broadcast/multicast strategy can be determined such that the minimum distortion of total received information is ***, a quality layer of data in a successively refined source may not be decodable if there is any loss of channel codewords, even if the corresponding longterm channel realization is su cient for decoding. To overcome this problem, one of the previous studies introduced a framework of coded video multicast, where multiple description coding (MDC) is applied to an SR content source and is further mapped into a layered modulation via SPC at the channel. Up till now, there has not been a rigorous proof provided on the bene t of manipulating the two coding techniques, (i.e. MDC and SPC), nor has any systematic optimization

关键词： power allocation multiple description coding relay channel broadcast/multicast strategy

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A SYSTEM FOR STREAMING MEDIA BASED ON SYNCHRONIZED multiple descriptionS coding

A SYSTEM FOR STREAMING MEDIA BASED ON SYNCHRONIZED MULTIPLE ...

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2nd IEEE International Conference on Broadband Network and Multimedia Technology

作者： Zhang Youwei Wu Chanle Wuhan Univ Natl Engn Res Ctr Multimedia Software Wuhan 430072 Peoples R China

ISBN: (纸本)9781424450053

Nowadays, many application layer multicast protocols (ALM) in which multiple description coding (MDC) is introduced have been proved to be more scalable and stable than traditional multicast protocols in practical environment. In this paper, we propose an ALM system called SMSD based on synchronized MDC for streaming media to address the synchronization of available descriptions. SMSD focuses on the video quality, firstly hosts can join the different overlay trees in different layers simultaneously, then the maximum covering set is worked out based on acquired descriptions information to achieve the best video quality, the quality management module with much low overhead is responsible for monitoring the variation of cached content due to departure of parents and activating the re-join procedure. Simulations implemented on Internet-like topology indicate that SMSD achieves higher video quality, lower control traffic than traditional ALM protocols, and comparable latency, link stress and robustness are achieved as well.

关键词： application layer multicast overlay tree streaming media synchronization video quality multiple description coding

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multiple description image compression based on multiwavelets

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INTERNATIONAL JOURNAL OF WAVELETS MULTIRESOLUTION AND INFORMATION PROCESSING 2019年第1期17卷

作者： Wang, Ning Ge, Shuangkui Li, Baobin Peng, Lizhong Beijing Inst Elect Technol & Applicat Beijing 100871 Peoples R China Univ Chinese Acad Sci Sch Comp & Control Beijing 100190 Peoples R China Peking Univ Sch Math Sci Beijing 100871 Peoples R China

multiple description coding (MDC) is one of the source coding techniques to alleviate the problems of packet loss in the network. The decoder estimates the lost signals from received ones, based on the certain statistical correlation between descriptions. However, this correlation also leads to compression redundancy at the same time. Therefore, how to make efficient use of the introduced correlation has great importance in practical MDC approaches. In this paper, we propose a multiple description image coding scenario based on balanced multiwavelets. Two simple and effective methods to reconstruct the original image from partial descriptions are suggested. Furthermore, optimization criterion corresponding to this multiwavelet based system is provided. According to this criterion, we can choose appropriate multifilter banks to satisfy different demands. Experimental results show that the optimized multifilter banks in a simulated transform coding environment perform very well.

关键词： multiple description coding rate-distortion theory multifilter bank balanced multiwavelet transform coding

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Reliable 3D video streaming considering region of interest

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EURASIP JOURNAL ON IMAGE AND VIDEO PROCESSING 2018年第1期2018卷 43页

作者： Rahimi, Ehsan Joslin, Chris Carleton Univ Dept Syst & Comp Engn 1125 Colonel By Dr Ottawa ON K1S 5B6 Canada Carleton Univ Sch Informat Technol 1125 Colonel By Dr Ottawa ON K1S 5B6 Canada

3D video applications are growing more common as communication technology becomes more predominant nowadays. With such increasing demand for the 3D multimedia services in either the wired or wireless networks, robust methods of video streaming will be introduced to show more favorable efficiency outcomes since packet failure is an integral characteristic of communication networks. This paper aims to introduce a new reliable method of stereoscopic video streaming based on multiple description coding (MDC) strategy. The proposed multiple description coding generates four 3D video descriptions considering the interesting objects contained in the scene. To be able to find the interesting objects in the scene, we use two metrics from the second-order statistics of the depth map image in a block-wise manner. Having detected the objects, the proposed multiple description coding algorithm generates the descriptions for the color video using a nonidentical decimation method with respect to the identified objects. To show how much reliable the proposed MDC method is, this article assumes that due to the unreliable communication channel, only one description, among four encoded descriptions, is delivered to the receiver successfully. Therefore, the receiver needs to estimate the missed descriptions' data from the available description. Since the human eye is more sensitive to objects than it is to pixels, the proposed method provides a better visual performance in view of its subjective assessment. Although, the objective test results verify the fact that the proposed method provides an improved performance than the Polyphase SubSampling (PSS) multiple description coding and our previous work using pixel variation. Regarding the depth map image, the proposed method generates the multiple descriptions according to the pixel prediction difficulty level. The considerable improvement achieved by the proposed method is shown with the peak signal-to-noise ratio (PSNR) and Structural

关键词： 3D stereoscopic videos Color video Depth map image Reliable multimedia streaming multiple description coding Object identification

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QoS-aware routing protocol using adaptive retransmission of distorted descriptions in MDC for MANETs

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INTERNATIONAL JOURNAL OF AD HOC AND UBIQUITOUS COMPUTING 2018年第1期28卷 55-67页

作者： Bhardwaj, Diwakar Kant, Krishna Chauhan, Durg Singh GLA Univ Dept Comp Engn & Applicat Mathura 281406 India Dept Comp Engn & Applicat Bangalore Karnataka India

Quality of service (QoS) of delay sensitive application like video stream is majorly affected by instantaneous channel conditions over noisy mobile ad-hoc networks (MANETs). Methods like forward error correction (FEC) and automatic repeat request (ARQ), multiple descnption coding (MDC), and MDC with error correction (MDC_EC) design to recover the quality of the video in noisy wireless networks under perform m MANETs because of their high overheads and high retransmission delay. MDC and MDC_EC produce unacceptable video quality at the receiver and fail to fulfil the QoS requirements of the video applications. We have proposed a novel routing protocol to support QoS and reduce overheads. The proposed work is twofold: i) redefine the distortion model to estimate the distortion of the transmitted video;ii) proposed a novel routing protocol model to mitigate the impact of channel noise on the video quality through selected retransmission of noisy descriptors (MDC_EC_RE).

关键词： signal-to-noise ratio SNR forward error correction FEC multiple description coding MDC mobile ad-hoc networks MANETs quality of service QoS distortion cross-layer design CLD noisy channels

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Channel coding for Progressive Images in a 2-D Time-Frequency OFDM Block With Channel Estimation Errors

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2009年第11期18卷 2476-2490页

作者： Toni, Laura Chan, Yee Sin Cosman, Pamela C. Milstein, Laurence B. Italian Inst Technol TERA Genoa Italy Univ Bologna WiLab Bologna Italy Verizon Corp Technol Walnut Creek CA 94597 USA Univ Calif San Diego Dept Elect & Comp Engn La Jolla CA 92093 USA

coding and diversity are very effective techniques for improving transmission reliability in a mobile wireless environment. The use of diversity is particularly important for multimedia communications over fading channels. In this work, we study the transmission of progressive image bitstreams using channel coding in a 2-D time-frequency resource block in an OFDM network, employing time and frequency diversities simultaneously. In particular, in the frequency domain, based on the order of diversity and the correlation of individual subcarriers, we construct symmetric n-channel FEC-based multiple descriptions using channel erasure codes combined with embedded image coding. In the time domain, a concatenation of RCPC codes and CRC codes is employed to protect individual descriptions. We consider the physical channel conditions arising from various coherence bandwidths and coherence times, leading to a range of orders of diversities available in the time and frequency domains. We investigate the effects of different error patterns on the delivered image quality due to various fade rates. We also study the tradeoffs and compare the relative effectiveness associated with the use of erasure codes in the frequency domain and convolutional codes in the time domain under different physical environments. Both the effects of intercarrier interference and channel estimation errors are included in our study. Specifically, the effects of channel estimation errors, frequency selectivity and the rate of the channel variations are taken into consideration for the construction of the 2-D time-frequency block. We provide results showing the gain that the proposed model achieves compared to a system without temporal coding. In one example, for a system experiencing flat fading, low Doppler, and imperfect CSI, we find that the increase in PSNR compared to a system without time diversity is as much as 9.4 dB.

关键词： Channel coding cross-layer design diversity multimedia communications multiple description coding orthogonal frequency division multiplexing (OFDM) progressive transmission wireless video

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