In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discr...In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discrete linear system with state and control constraints. Then we apply the discrete maximum principle to get the optimal solution. Experimental results are given in the end. Compared with traditional algorithms, the proposed algorithm is suitable for the coder with continuous output rates, and can achieve the better solution. Our algorithm can be used in both off-line and on-line coding.展开更多
he objective of the paper is to clarify the contradictory opinions about the effect of long range dependence (LRD) on the performance of queueing system. In order to investigate the impact of the value of LRD on the p...he objective of the paper is to clarify the contradictory opinions about the effect of long range dependence (LRD) on the performance of queueing system. In order to investigate the impact of the value of LRD on the performance of queueing system, a particular source (Star War) is used, whose Pframe and Bframe show the same frame size distribution and the same autocorrelation structure (i.e. the similar SRD and LRD) and the different values. The “Shuffling Operation” changing the order of original time series in some way is used to remove either SRD or LRD. The conditions under which LRD or SRD makes the dominant impact on single server FIFO queue and the importance of the amount of LRD are found after a set of queueing experiments.展开更多
This paper is concerning of Erlang formulas practical approval and their usage with video flow transfer in IP networks. Erlang formulas were simulated in MATLAB program. Practical verification was realized in defined ...This paper is concerning of Erlang formulas practical approval and their usage with video flow transfer in IP networks. Erlang formulas were simulated in MATLAB program. Practical verification was realized in defined environment by using of designed video source. The result is comparison of loss calculated by MATLAB and loss of real video data transfer.展开更多
Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia applications.However,plentiful challenges to VBR video service provision have been raised for its characteristic of high...Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia applications.However,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic abruptness.To support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management scheme.This scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management reference.In addition,to support multi-user application,an adjustment priorities classified strategy is also put forward.Finally,a test-bed based on this management scheme is established.The experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.展开更多
In this paper we discuss how to select appropriate source and channel rate for transporting variable bit-rate (VBR) compressed video over QoS (quality of service)-assured channels. We first formulate it as an optimal ...In this paper we discuss how to select appropriate source and channel rate for transporting variable bit-rate (VBR) compressed video over QoS (quality of service)-assured channels. We first formulate it as an optimal control problem of discrete linear time-delay system. Then the discrete maximum principle is used to get the optimal control. Compared to traditional solutions, the proposed algorithm is designed for the coder with continuous output rate, and can work without special requirements for the encoder and decoder buffer sizes. Theoretical analysis and experimental results show that the proposed algorithm has lower space and time complexity. Our solution can be used in both off-line and on-line coding.展开更多
文摘In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discrete linear system with state and control constraints. Then we apply the discrete maximum principle to get the optimal solution. Experimental results are given in the end. Compared with traditional algorithms, the proposed algorithm is suitable for the coder with continuous output rates, and can achieve the better solution. Our algorithm can be used in both off-line and on-line coding.
文摘he objective of the paper is to clarify the contradictory opinions about the effect of long range dependence (LRD) on the performance of queueing system. In order to investigate the impact of the value of LRD on the performance of queueing system, a particular source (Star War) is used, whose Pframe and Bframe show the same frame size distribution and the same autocorrelation structure (i.e. the similar SRD and LRD) and the different values. The “Shuffling Operation” changing the order of original time series in some way is used to remove either SRD or LRD. The conditions under which LRD or SRD makes the dominant impact on single server FIFO queue and the importance of the amount of LRD are found after a set of queueing experiments.
文摘This paper is concerning of Erlang formulas practical approval and their usage with video flow transfer in IP networks. Erlang formulas were simulated in MATLAB program. Practical verification was realized in defined environment by using of designed video source. The result is comparison of loss calculated by MATLAB and loss of real video data transfer.
基金supported by the National Basic Research Program of China (2007CB310705)the National Natural Science Foundation of China (60772024, 60711140087)+4 种基金the Hi-Tech Research and Development Program of China (2007AA01Z255)the NCET (06-0090)the PCSIRT (IRT0609)the ISTCP (2006DFA11040)the 111 Project of China (B07005)
文摘Real-time variable bit rate（VBR） video is expected to take a significant portion of multimedia applications.However,plentiful challenges to VBR video service provision have been raised for its characteristic of high traffic abruptness.To support multi-user real-time VBR video transmission with high bandwidth utilization and satisfied quality of service（QoS）,this article proposes a practical dynamic bandwidth management scheme.This scheme forecasts future media rate of VBR video by employing time-domain adaptive linear predictor and using media delivery index（MDI） as both QoS measurement and complementary management reference.In addition,to support multi-user application,an adjustment priorities classified strategy is also put forward.Finally,a test-bed based on this management scheme is established.The experimental results demonstrate that the scheme proposed in this article is efficient with bandwidth utilization increased by 20%-60% compared to a fixed service rate and QoS guaranteed.
文摘In this paper we discuss how to select appropriate source and channel rate for transporting variable bit-rate (VBR) compressed video over QoS (quality of service)-assured channels. We first formulate it as an optimal control problem of discrete linear time-delay system. Then the discrete maximum principle is used to get the optimal control. Compared to traditional solutions, the proposed algorithm is designed for the coder with continuous output rate, and can work without special requirements for the encoder and decoder buffer sizes. Theoretical analysis and experimental results show that the proposed algorithm has lower space and time complexity. Our solution can be used in both off-line and on-line coding.
