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Multiple description video coding using GOB alternation and low quality macroblock update
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作者 Wang Yangli Wu Chengke 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期792-796,共5页
To combat packet loss and realize robust video transmission over Intemet and wireless networks, a new multiple description (MD) video coding method is proposed. In the method, two descriptions for each video frame i... To combat packet loss and realize robust video transmission over Intemet and wireless networks, a new multiple description (MD) video coding method is proposed. In the method, two descriptions for each video frame is first created by group of blocks (GOB) alternation. Motion information is then duplicated in both the descriptions and a process called low quality macroblock update is designed to redundantly encode textures in each frame using standard bit stream syntax. In this way, the output bit streams are standard compliant and better trade-offs between redundancy and single charmel reconstruction distortion are achieved. The proposed method has much better performance than the well-known MD transform coding (MDTC) method both in terms of redundancy rate distortion, and in the packet loss scenario. 展开更多
关键词 video transmission packet loss multiple description redundancy rate distortion low quality macroblock update.
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Improved Multiple Descriptions Sinusoidal Coder Adaptive to Packet Loss Rate
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作者 郎玥 王晶 +1 位作者 赵胜辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期202-207,共6页
To make the multiple descriptions codec adaptive to the packet loss rate, which can minimize the final distortion, a novel adaptive multiple descriptions sinusoidal coder (AMDSC) is proposed, which is based on a sin... To make the multiple descriptions codec adaptive to the packet loss rate, which can minimize the final distortion, a novel adaptive multiple descriptions sinusoidal coder (AMDSC) is proposed, which is based on a sinusoidal model and a noise model. Firstly, the sinusoidal parameters are extracted in the sinusoidal model, and ordered in a decrease manner. Odd indexed and even indexed parameters are divided into two descriptions. Secondly, the output vector from the noise model is split vector quantized. And the two sub-vectors are placed into two descriptions too. Finally, the number of the extracted parameters and the redundancy between the two descriptions are adjusted according to the packet loss rate of the network. Analytical and experimental resuits show that the proposed AMDSC outperforms existing MD speech coders by taking network loss characteristics into account. Therefore, it is very suitable for unreliable channels 展开更多
关键词 speech coding multiple descriptions coding sinusoidal model
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Multiple descriptions based wavelet image coding
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作者 陈海林 杨宇航 《Journal of Zhejiang University Science》 EI CSCD 2004年第1期55-61,共7页
We present a simple and efficient scheme that combines multiple descriptions coding with wavelet transform under JPEG2000 image coding architecture. To reduce packet losses, controlled amounts of redundancy are added ... We present a simple and efficient scheme that combines multiple descriptions coding with wavelet transform under JPEG2000 image coding architecture. To reduce packet losses, controlled amounts of redundancy are added to the wavelet transform coefficients to produce multiple descriptions of wavelet coefficients during the compression process to produce multiple descriptions bit-stream of a compressed image. Even if areceiver gets only parts of descriptions (other descriptions being lost), it can still reconstruct image with acceptable quality. Specifically, the scheme uses not only high-performance wavelet transform to improve compression efficiency, but also multiple descriptions technique to enhance the robustness of the compressed image that is transmitted through unreliable network channels. 展开更多
关键词 multiple descriptions Discrete wavelet transform (DWT) JPEG2000
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LOW-COMPLEXITY REDUNDANCY INSERTION IN MULTIPLE DESCRIPTION CODING
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作者 Yang Rener Li Jinxiang Wen Huafeng 《Journal of Electronics(China)》 2008年第3期409-414,共6页
Multiple description coding has recently been proposed as a joint source and channel coding to solve the problem of robust image transmission over unreliable network, and it can offer a variety of tradeoff between sig... Multiple description coding has recently been proposed as a joint source and channel coding to solve the problem of robust image transmission over unreliable network, and it can offer a variety of tradeoff between signal redundancy and transmission robustness. In this letter, a novel pre- and post-processing method with flexible redundancy insertion for polyphase downsampling multiple de- scription coding is presented. The proposed method can be implemented as pre- and post-processing to all standards for image and video communications, with obvious advantages. Simulation results show that this approach can reduce the computational complexity while provide a flexible redundancy in- sertion to make the system robust for any packet loss situation over different networks. 展开更多
关键词 multiple description image coding Polyphase downsampling Redundancy insertion
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Robust multiple description distributed video coding using optimized zero-padding 被引量:2
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作者 WANG AnHong ZHAO Yao BAI HuiHui 《Science in China(Series F)》 2009年第2期206-214,共9页
Distributed video coding (DVC) arouses high interests due to its property of low-complexity encoding. This paper proposes a robust multiple description DVC (MDDVC) under the constraint of low-complexity encoding. ... Distributed video coding (DVC) arouses high interests due to its property of low-complexity encoding. This paper proposes a robust multiple description DVC (MDDVC) under the constraint of low-complexity encoding. In MDDVC, zeros are padded to each frame and the resulting big-size video is divided into multiple descriptions. Then, each description is compressed by s hybrid DVC (HDVC) codec and trans- mitted over different channel. When one channel does not work, the lost HDVC description is estimated by the received from other channel, which guarantees the robustness of the system; MDDVC moves the complex motion estimation totally to the decoder so it features low-complexity encoding. In the pre-processing, an optimized zero-padding is also proposed to improve the performance. Experimental results exhibit that the proposed MDDVC scheme achieves better rate-distortion performance and robustness than the referenced especially when packet-loss rate is high. 展开更多
关键词 distributed video coding ROBUSTNESS multiple description coding zero-padding
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Chessboard-interpolation-based multiple description video coding 被引量:2
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作者 FANChen CUIHuijuan TANGKun 《Science in China(Series F)》 2004年第1期66-74,共9页
To enhance the robustness of video transmission over noisy channels, this paper presents a multiple description video coding algorithm based on chessboard-interpolation. In the algorithm, the input image is decomposed... To enhance the robustness of video transmission over noisy channels, this paper presents a multiple description video coding algorithm based on chessboard-interpolation. In the algorithm, the input image is decomposed according to the chessboard pattern, and then interpolated to produce two approximate images with the same resolution. Consequently, the state-of-the-art DCT+MC (Discrete Cosine Transform + Motion Compensation) video codec is independently applied to the two approximate images to generate two descriptions of the original image. In this framework, a fairely good reconstructed image quality is obtained when two descriptions are received simultaneously, while an acceptable reconstructed image quality could be yielded if only one description is available. Moreover, the mismatch between the encoder and the decoder could be effectively controlled through partial coding of the difference signal between two descriptions. In bidirectional video communications, a drift control scheme is further proposed, in which the error drift could be eliminated after the encoder imitating the error concealment actions of the decoder. Since the inherent correlation among adjacent blocks of DCT+MC video coding is efficiently exploited, this algorithm has a better redundancy-rate-distortion (RRD) performance than other multiple description algorithms. Simulation results show that the proposed algorithm is fairly robust while preserves a high compression rate. A more constant reconstructed image quality is achieved over extremely noisy channels, compared with traditional single description coding. In addition, it is observed that the mismatch and the error drift are effectively controlled. 展开更多
关键词 video coding multiple description coding chessboard interpolation error drift.
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Efficient Multiple Description Scalable Video Coding Scheme Based on Weighted Signal Combinations 被引量:1
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作者 赵安邦 王文生 +1 位作者 崔慧娟 唐昆 《Tsinghua Science and Technology》 SCIE EI CAS 2007年第1期86-90,共5页
A simple, efficient multiple description coding (MDC) algorithm was developed based on weighted signal combinations. The scheme uses the standard video encoder with a pre-processing stage to generate multiple descri... A simple, efficient multiple description coding (MDC) algorithm was developed based on weighted signal combinations. The scheme uses the standard video encoder with a pre-processing stage to generate multiple descriptions. The decoder then uses a post-processing algorithm to combine the descriptions to provide better image quality. A scalable codec in the MDC system allows the system to provide multiple descriptions and scalability at the same time. In addition, since the different scalable descriptions may have different qualities, a simple averaging process is not optimal. An optimal weighted combination of the two descriptions was developed based on the signal to noise ratios. Compared with the simple average combination, the algorithm significantly improved the video quality, especially with large quality differences between the two descriptions, with gains of up to 3.56 dB. 展开更多
关键词 multiple description video coding fine grained scalable video coding video transmission
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Multiple description video coding based on residuum compensation 被引量:1
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作者 ZHAO AnBang YU Yun SUN GuoCang LI GuanFang HUI JunYing 《Science in China(Series F)》 2009年第8期1439-1445,共7页
As one of the focus areas of robust video coding and transmission, multiple description video coding has attracted comprehensive attention. The low coding efficiency of multiple description video coding is always the ... As one of the focus areas of robust video coding and transmission, multiple description video coding has attracted comprehensive attention. The low coding efficiency of multiple description video coding is always the major challenge in this field. In order to improve the performance of multiple description video coding, this paper proposes a scheme based on residuum compensation. In this scheme, each original video frame is encoded with a traditional encoder first to get the first description. Then the error residuum of each coded frame is added up to the corresponding original frame and the resulting compensated frame is encoded by another traditional encoder to generate the second description suc- cessively. This work uses JM10.0 of H.264/AVC as video coding codec to conduct the experiments. The experimental results show that the proposed scheme has good coding performance. Compared to state of art traditional single description encoder, the efficiency can be as high as 90%, he. the redundancy is only 10% to 20%. 展开更多
关键词 multiple description coding successive refinement coding noise streaming transmission
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Complete Multiple Description Mesh-Based Video Coding Scheme and Its Performance
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作者 Yang-LiWang Cheng-KeWu 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第3期426-431,共6页
This paper proposes a multiple description (MD) mesh-based motion coding method, which generates two descriptions for mesh-based motion by subsampling the nodes of a right-angled triangular mesh and dividing them into... This paper proposes a multiple description (MD) mesh-based motion coding method, which generates two descriptions for mesh-based motion by subsampling the nodes of a right-angled triangular mesh and dividing them into two groups. Motion vectors associated with the mesh nodes in each group are transmitted over distinct channels. With the nodes in each group, two other regular triangular meshes besides the original one can be constructed, and three different prediction images can be reconstructed according to descriptions available. The proposed MD mesh-based motion coding method is then combined with the pairwise correlating transform (PCT), and a complete MD video coding scheme is proposed. Further measures are taken to reduce the mismatch between the encoder and decoder that occurs when only one description is received and the decoder reconstruction is different from the encoder. The performance of the proposed scheme is evaluated using computer simulations, and the results show, compared to Reibman's MD transform coding (MDTC) method, the proposed scheme achieves better redundancy rate distortion (RRD) performance. In packet loss scenario, the proposed scheme outperforms the MDTC method. 展开更多
关键词 multiple description coding mesh-based motion compensation redundancy rate distortion packet loss
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Multipath Routing of Multiple Description Coded Images in Wireless Networks
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作者 徐媛媛 朱策 虞露 《Journal of Computer Science & Technology》 SCIE EI CSCD 2014年第4期576-588,共13页
Multiple description coding (MDC) generates multiple decodable bitstreams for a source to combat informa- tion loss. In this paper, multipath routing problem for two-description coded images is investigated for trad... Multiple description coding (MDC) generates multiple decodable bitstreams for a source to combat informa- tion loss. In this paper, multipath routing problem for two-description coded images is investigated for traditional and coded wireless networks without and with coding capability at intermediate nodes, respectively. Firstly, we formulate an interference-aware MDC multipath routing for traditional networks by employing a time-division link scheduling method to eliminate wireless interference, and ultimately obtain an optimal path selection corresponding to the minimum achievable distortion. Secondly, for coded networks, we evaluate practical wireless network coding (NC) in delivering descriptions of multiple unicast sessions. While NC increases maximum supporting flow rate of MDC descriptions in wireless networks, possible undecodability of NC mixed information is alleviated by MDC. To minimize achievable distortion, a proposed interference-and-coding-aware MDC multipath routing strikes a good balance between minimizing side effect of wireless interference avoidance and maximizing NC opportunity. Simulation results validate the effectiveness of the two proposed schemes. 展开更多
关键词 multiple description coding multipath routing network coding wireless interference
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M3FEC:Joint Multiple Description Coding and Forward Error Correction for Interactive Multimedia in Multiple Path Transmission
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作者 张辉 江伟 +2 位作者 周晋 陈震 李军 《Tsinghua Science and Technology》 SCIE EI CAS 2011年第3期320-331,共12页
The best-effort internet has inherent limitations on the end-to-end performance for interactive multimedia communications. This paper presents a multiple description coding (MDC) and forward error correction (FEC)... The best-effort internet has inherent limitations on the end-to-end performance for interactive multimedia communications. This paper presents a multiple description coding (MDC) and forward error correction (FEC) based multiple path transmission schemes for interactive multimedia (M3FEC), which improves the end users’ experience by maximizing a rate-distortion (R-D) based optimization problem. The proposed model considers both the network diversity and the application’s stringent requirements, and combines the individual merits of the three promising technologies of multiple path overlay routing, MDC and FEC. Extensive numerical analysis and PlanetLab experiments demonstrate that M3FEC successfully combats packet losses, error propagation, and unpredictable network dynamics. This method also significantly increases distortion for interactive multimedia by over 10 dB than traditional IP-layer single path transmission in poor network environments, and outperforms the performance achieved by using MDC or FEC alone. 展开更多
关键词 interactive multimedia multiple path overlay routing multiple description coding (MDC) forward error correction (FEC) rate-distortion (R-D)
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Scalable Compression Algorithm for Video Monitoring System
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作者 王一拙 石峰 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期129-133,共5页
A layered compression algorithm is presented which delivers spatial scalable encoded bit streams for remote video monitoring system. The complexity of the algorithm is modest and is well suited to real time implementa... A layered compression algorithm is presented which delivers spatial scalable encoded bit streams for remote video monitoring system. The complexity of the algorithm is modest and is well suited to real time implementation. Based on the layered compression algorithm, a codec system model is established. High-speed video compression can be realized with parallel data compression in this codec system. For image reconstruction, a prediction method using two nearest pix points is presented. 展开更多
关键词 scalable compression layered compression video monitoring system multiple description coding
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Robust and Scalable P2P Live Streaming
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作者 陈锬 熊馨 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期482-488,共7页
Distributing real-time video stream in large scale group communication over Interuet poses several challenging problems due to the complex network dynamics, stringent requirement of delay and loss. This paper proposes... Distributing real-time video stream in large scale group communication over Interuet poses several challenging problems due to the complex network dynamics, stringent requirement of delay and loss. This paper proposes a novel peer-to-peer scheme, named TeamCast, to combat with these issues. Constructing multiple diverse application layer multicast (ALM) trees to transmit multiple independent complementary descriptions produced by multiple description coding (MDC) simultaneously, TeamCast improves error resilient ability in the presence of various levels of packet loss caused by unpredictable congestion of Internet and node failure, as well as enlarges system capacity. The results of extensive simulations indicate that TeamCast achieves low latency, scalability, and fault tolerance for the delivery of live media stream. 展开更多
关键词 path diversity multiple description coding application layer multicast media streaming topologyuware
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A NEW UEP SCHEME FOR ROBUST VIDEO TRANSMISSION IN LDPC CODED MIMO-OFDM SYSTEM
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作者 Ru Congchong Zheng Haifeng +2 位作者 Yin Liuguo Lu Jianhua Chen Changwen 《Journal of Electronics(China)》 2007年第3期396-401,共6页
In order to improve the video transmission performance in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system, a new scheme, which integrates Multiple Description Coding (MD... In order to improve the video transmission performance in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system, a new scheme, which integrates Multiple Description Coding (MDC), Low Density Parity Check (LDPC) coding and hybrid space time coding, is proposed in this letter. In particular, a hybrid space time coding algorithm is combined with LDPC codes to perform Unequal Error Protection (UEP) of MDC encoded video streams. Comparing with the UEP transmission with only LDPC codes, the proposed scheme achieves more than ldB gain in terms of Signal to Noise Ratio (SNR) when the Peak Signal to Noise Ratio (PSNR) of reconstructed video is above 30dB. 展开更多
关键词 multiple-Input multiple-Output Orthogonal Frequency Division multiplexing (MIMO-OFDM) multiple description Coding (MDC) Low Density Parity Check (LDPC) Unequal Error Protection (UEP)
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