The Experts below are selected from a list of 47754 Experts worldwide ranked by ideXlab platform
Fernando Pereira - One of the best experts on this subject based on the ideXlab platform.
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Evaluating a Feedback Channel based transform domain Wyner-Ziv video codec
Signal Processing: Image Communication, 2008Co-Authors: Catarina Brites, Jose Quintas Pedro, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding-a particular case of distributed video coding (DVC)-is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. In recent years, some practical WZ video coding solutions have been proposed with promising results. One of the most popular WZ video coding architectures in the literature uses turbo codes based Slepian-Wolf coding and a Feedback Channel to perform rate control at the decoder. This WZ video coding architecture has been first proposed by researchers at Stanford University and has been after adopted and improved by many research groups around the world. However, while there are many papers published with changes and improvements to this architecture, the precise and detailed evaluation of its performance, targeting its deep understanding for future advances, has not been made. Available performance results are mostly partial, under unclear and incompatible conditions, using vaguely defined and also sometimes architecturally unrealistic codec solutions. This paper targets the provision of a detailed, clear, and complete performance evaluation of an advanced transform domain WZ video codec derived from the Stanford turbo coding and Feedback Channel based architecture. Although the WZ video codec proposed for this evaluation is among the best available, the main purpose and novelty of this paper is the solid and comprehensive performance evaluation made which will provide a strong, and very much needed, performance reference for researchers in this WZ video coding field, as well as a solid way to steer future WZ video coding research.
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studying the gop size impact on the performance of a Feedback Channel based wyner ziv video codec
Pacific-Rim Symposium on Image and Video Technology, 2007Co-Authors: Fernando Pereira, Joao Ascenso, Catarina BritesAbstract:Wyner-Ziv video coding has become one of the hottest research topics in the video coding community due to the conceptual, theoretical and functional novelties it brings. Among the many practical architectures already available, Feedback Channel-based with Channel coding, e.g. LDPC and turbo codes, solutions are rather popular. These solutions rely on decoder motion estimation based on periodic Intra coded key frames, setting the so-called GOP size, very much like in conventional video coding. This paper targets the ratedistortion and complexity performance study of this type of Wyner-Ziv coding solution as a function of the GOP size, considering both LPDC and turbo codes.
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studying error resilience performance for a Feedback Channel based transform domain wyner ziv video codec
Picture Coding Symposium, 2007Co-Authors: Jose Quintas Pedro, Catarina Brites, Carlos Bandeirinha, Shuiming Ye, Luis Ducla Soares, Joao Ascenso, Frédéric Dufaux, Fernando Pereira, Touradj EbrahimiAbstract:Wyner-Ziv (WZ) video coding is an emerging video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. One of the most interesting and used WZ video coding architectures makes use of a Feedback Channel (FC) to perform rate control at the decoder; in this context, the Slepian-Wolf coding module is typically based on turbo coding with puncturing. Because WZ coding is not based on the prediction loop used in conventional video coding but rather on a statistical approach where a decoder estimation of the frame to be coded is ‘corrected’ by the encoder, it provides intrinsic error resilience capabilities. This paper intends to study the error resilience performance of a Feedback Channel based transform domain WZ codec using appropriate scenarios and conditions, notably in comparison with the best performing H.264/AVC standard
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EUSIPCO - Feedback Channel in pixel domain Wyner-Ziv video coding: Myths and realities
2006Co-Authors: Catarina Brites, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding - a particular case of distributed video coding (DVC) - is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. Recently, practical WZ video coding solutions were proposed with promising results. Many of the solutions available in the literature make use of a Feedback Channel (FC) to perform rate control at the decoder. In this context, this paper intends to analyse the impact of this Feedback Channel, notably through a number of metrics such as the frequency the Feedback Channel is used as well as its associated rate. It is also presented a study on the evolution of the decoded frames quality as more parity bits are requested via Feedback Channel. Those measures are important since they allow characterizing the usage of the Feedback Channel, and have never been presented in the literature.
Catarina Brites - One of the best experts on this subject based on the ideXlab platform.
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Evaluating a Feedback Channel based transform domain Wyner-Ziv video codec
Signal Processing: Image Communication, 2008Co-Authors: Catarina Brites, Jose Quintas Pedro, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding-a particular case of distributed video coding (DVC)-is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. In recent years, some practical WZ video coding solutions have been proposed with promising results. One of the most popular WZ video coding architectures in the literature uses turbo codes based Slepian-Wolf coding and a Feedback Channel to perform rate control at the decoder. This WZ video coding architecture has been first proposed by researchers at Stanford University and has been after adopted and improved by many research groups around the world. However, while there are many papers published with changes and improvements to this architecture, the precise and detailed evaluation of its performance, targeting its deep understanding for future advances, has not been made. Available performance results are mostly partial, under unclear and incompatible conditions, using vaguely defined and also sometimes architecturally unrealistic codec solutions. This paper targets the provision of a detailed, clear, and complete performance evaluation of an advanced transform domain WZ video codec derived from the Stanford turbo coding and Feedback Channel based architecture. Although the WZ video codec proposed for this evaluation is among the best available, the main purpose and novelty of this paper is the solid and comprehensive performance evaluation made which will provide a strong, and very much needed, performance reference for researchers in this WZ video coding field, as well as a solid way to steer future WZ video coding research.
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studying the gop size impact on the performance of a Feedback Channel based wyner ziv video codec
Pacific-Rim Symposium on Image and Video Technology, 2007Co-Authors: Fernando Pereira, Joao Ascenso, Catarina BritesAbstract:Wyner-Ziv video coding has become one of the hottest research topics in the video coding community due to the conceptual, theoretical and functional novelties it brings. Among the many practical architectures already available, Feedback Channel-based with Channel coding, e.g. LDPC and turbo codes, solutions are rather popular. These solutions rely on decoder motion estimation based on periodic Intra coded key frames, setting the so-called GOP size, very much like in conventional video coding. This paper targets the ratedistortion and complexity performance study of this type of Wyner-Ziv coding solution as a function of the GOP size, considering both LPDC and turbo codes.
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studying error resilience performance for a Feedback Channel based transform domain wyner ziv video codec
Picture Coding Symposium, 2007Co-Authors: Jose Quintas Pedro, Catarina Brites, Carlos Bandeirinha, Shuiming Ye, Luis Ducla Soares, Joao Ascenso, Frédéric Dufaux, Fernando Pereira, Touradj EbrahimiAbstract:Wyner-Ziv (WZ) video coding is an emerging video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. One of the most interesting and used WZ video coding architectures makes use of a Feedback Channel (FC) to perform rate control at the decoder; in this context, the Slepian-Wolf coding module is typically based on turbo coding with puncturing. Because WZ coding is not based on the prediction loop used in conventional video coding but rather on a statistical approach where a decoder estimation of the frame to be coded is ‘corrected’ by the encoder, it provides intrinsic error resilience capabilities. This paper intends to study the error resilience performance of a Feedback Channel based transform domain WZ codec using appropriate scenarios and conditions, notably in comparison with the best performing H.264/AVC standard
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EUSIPCO - Feedback Channel in pixel domain Wyner-Ziv video coding: Myths and realities
2006Co-Authors: Catarina Brites, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding - a particular case of distributed video coding (DVC) - is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. Recently, practical WZ video coding solutions were proposed with promising results. Many of the solutions available in the literature make use of a Feedback Channel (FC) to perform rate control at the decoder. In this context, this paper intends to analyse the impact of this Feedback Channel, notably through a number of metrics such as the frequency the Feedback Channel is used as well as its associated rate. It is also presented a study on the evolution of the decoded frames quality as more parity bits are requested via Feedback Channel. Those measures are important since they allow characterizing the usage of the Feedback Channel, and have never been presented in the literature.
Joao Ascenso - One of the best experts on this subject based on the ideXlab platform.
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Evaluating a Feedback Channel based transform domain Wyner-Ziv video codec
Signal Processing: Image Communication, 2008Co-Authors: Catarina Brites, Jose Quintas Pedro, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding-a particular case of distributed video coding (DVC)-is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. In recent years, some practical WZ video coding solutions have been proposed with promising results. One of the most popular WZ video coding architectures in the literature uses turbo codes based Slepian-Wolf coding and a Feedback Channel to perform rate control at the decoder. This WZ video coding architecture has been first proposed by researchers at Stanford University and has been after adopted and improved by many research groups around the world. However, while there are many papers published with changes and improvements to this architecture, the precise and detailed evaluation of its performance, targeting its deep understanding for future advances, has not been made. Available performance results are mostly partial, under unclear and incompatible conditions, using vaguely defined and also sometimes architecturally unrealistic codec solutions. This paper targets the provision of a detailed, clear, and complete performance evaluation of an advanced transform domain WZ video codec derived from the Stanford turbo coding and Feedback Channel based architecture. Although the WZ video codec proposed for this evaluation is among the best available, the main purpose and novelty of this paper is the solid and comprehensive performance evaluation made which will provide a strong, and very much needed, performance reference for researchers in this WZ video coding field, as well as a solid way to steer future WZ video coding research.
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studying the gop size impact on the performance of a Feedback Channel based wyner ziv video codec
Pacific-Rim Symposium on Image and Video Technology, 2007Co-Authors: Fernando Pereira, Joao Ascenso, Catarina BritesAbstract:Wyner-Ziv video coding has become one of the hottest research topics in the video coding community due to the conceptual, theoretical and functional novelties it brings. Among the many practical architectures already available, Feedback Channel-based with Channel coding, e.g. LDPC and turbo codes, solutions are rather popular. These solutions rely on decoder motion estimation based on periodic Intra coded key frames, setting the so-called GOP size, very much like in conventional video coding. This paper targets the ratedistortion and complexity performance study of this type of Wyner-Ziv coding solution as a function of the GOP size, considering both LPDC and turbo codes.
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studying error resilience performance for a Feedback Channel based transform domain wyner ziv video codec
Picture Coding Symposium, 2007Co-Authors: Jose Quintas Pedro, Catarina Brites, Carlos Bandeirinha, Shuiming Ye, Luis Ducla Soares, Joao Ascenso, Frédéric Dufaux, Fernando Pereira, Touradj EbrahimiAbstract:Wyner-Ziv (WZ) video coding is an emerging video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. One of the most interesting and used WZ video coding architectures makes use of a Feedback Channel (FC) to perform rate control at the decoder; in this context, the Slepian-Wolf coding module is typically based on turbo coding with puncturing. Because WZ coding is not based on the prediction loop used in conventional video coding but rather on a statistical approach where a decoder estimation of the frame to be coded is ‘corrected’ by the encoder, it provides intrinsic error resilience capabilities. This paper intends to study the error resilience performance of a Feedback Channel based transform domain WZ codec using appropriate scenarios and conditions, notably in comparison with the best performing H.264/AVC standard
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EUSIPCO - Feedback Channel in pixel domain Wyner-Ziv video coding: Myths and realities
2006Co-Authors: Catarina Brites, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding - a particular case of distributed video coding (DVC) - is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. Recently, practical WZ video coding solutions were proposed with promising results. Many of the solutions available in the literature make use of a Feedback Channel (FC) to perform rate control at the decoder. In this context, this paper intends to analyse the impact of this Feedback Channel, notably through a number of metrics such as the frequency the Feedback Channel is used as well as its associated rate. It is also presented a study on the evolution of the decoded frames quality as more parity bits are requested via Feedback Channel. Those measures are important since they allow characterizing the usage of the Feedback Channel, and have never been presented in the literature.
Jose Quintas Pedro - One of the best experts on this subject based on the ideXlab platform.
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Evaluating a Feedback Channel based transform domain Wyner-Ziv video codec
Signal Processing: Image Communication, 2008Co-Authors: Catarina Brites, Jose Quintas Pedro, Joao Ascenso, Fernando PereiraAbstract:Wyner-Ziv (WZ) video coding-a particular case of distributed video coding (DVC)-is a new video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. In recent years, some practical WZ video coding solutions have been proposed with promising results. One of the most popular WZ video coding architectures in the literature uses turbo codes based Slepian-Wolf coding and a Feedback Channel to perform rate control at the decoder. This WZ video coding architecture has been first proposed by researchers at Stanford University and has been after adopted and improved by many research groups around the world. However, while there are many papers published with changes and improvements to this architecture, the precise and detailed evaluation of its performance, targeting its deep understanding for future advances, has not been made. Available performance results are mostly partial, under unclear and incompatible conditions, using vaguely defined and also sometimes architecturally unrealistic codec solutions. This paper targets the provision of a detailed, clear, and complete performance evaluation of an advanced transform domain WZ video codec derived from the Stanford turbo coding and Feedback Channel based architecture. Although the WZ video codec proposed for this evaluation is among the best available, the main purpose and novelty of this paper is the solid and comprehensive performance evaluation made which will provide a strong, and very much needed, performance reference for researchers in this WZ video coding field, as well as a solid way to steer future WZ video coding research.
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studying error resilience performance for a Feedback Channel based transform domain wyner ziv video codec
Picture Coding Symposium, 2007Co-Authors: Jose Quintas Pedro, Catarina Brites, Carlos Bandeirinha, Shuiming Ye, Luis Ducla Soares, Joao Ascenso, Frédéric Dufaux, Fernando Pereira, Touradj EbrahimiAbstract:Wyner-Ziv (WZ) video coding is an emerging video coding paradigm based on two major Information Theory results: the Slepian-Wolf and Wyner-Ziv theorems. One of the most interesting and used WZ video coding architectures makes use of a Feedback Channel (FC) to perform rate control at the decoder; in this context, the Slepian-Wolf coding module is typically based on turbo coding with puncturing. Because WZ coding is not based on the prediction loop used in conventional video coding but rather on a statistical approach where a decoder estimation of the frame to be coded is ‘corrected’ by the encoder, it provides intrinsic error resilience capabilities. This paper intends to study the error resilience performance of a Feedback Channel based transform domain WZ codec using appropriate scenarios and conditions, notably in comparison with the best performing H.264/AVC standard
Dirk Dahlhaus - One of the best experts on this subject based on the ideXlab platform.
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ICC - Recursive Spatial Multiplexing with a capacity-limited Feedback Channel
2014 IEEE International Conference on Communications (ICC), 2014Co-Authors: Nour Mansour, Dirk Dahlhaus, Ibrahim Asghar Shah, Thomas HunzikerAbstract:A realistic Recursive Spatial Multiplexing (RSM) scheme for the case of a wireless Feedback Channel with limited capacity is considered where the identifier for the critical subspaces are encoded using either Grassmannian or vector quantizers. Optimum and suboptimum encoding schemes are proposed and analyzed. The threshold for the eigenvalues of the Channel matrix required in the receiver for determining the critical subspaces is chosen based on optimizing Channel capacity and uncoded biterror rates within the inner transceiver. It is shown that the limited Feedback Channel capacity limits the RSM performance, critically determines the achievable bit-error rates and defines the range of signal-to-noise ratio values where RSM outperforms open-loop multiple-input multiple-output transmission schemes.
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Feedback-aided selective subspace retransmission for outage-free spatial multiplexing
2007 6th International Conference on Information Communications & Signal Processing, 2007Co-Authors: Thomas Hunziker, Thomas Edlich, Dirk DahlhausAbstract:We study a novel spatial multiplexing scheme for a multiple-input/multiple-output (MIMO) architecture with vertical coding and a Feedback Channel. Rather than for sending back Channel state information (CSI), the Feedback Channel is used to request the retransmission of signal parts in critical signal subspaces. This enables the receiver to perform linear reconstruction of the layered signals without the destructive noise enhancement in ill-conditioned Channel matrices that is experienced with conventional linear processors. Moreover, a given target signal-to-noise ratio at the decoder input can be ensured. A comparison against standard MIMO architectures in terms of achievable throughput lets us conclude that the proposed multiplexing facilitates an advantageous closed-loop MIMO system which does not rely on accurate transmitter-side CSI.
