The transfer of prerecorded, compressed video requires multimedia services to support large uctuations in bandwidth requirements on multiple time scales. Bandwidth smoothing techniques can reduce the burstiness of a variable-bit-rate stream by prefetching data at a series of xed rates, simplifying the allocation of resources in video servers and the communication network. Given a xed client-sid...

A carrier offset correction scheme based on Maximum Likelihood (ML) method for the downlink of an Orthogonal Variable bit rate Multicarrier-CDMA (MCCDMA) scheme in a fast frequency selective Rayleigh fading channel is proposed and discussed. The proposed methodology assumes perfect knowledge of phase offset, whereas an Equal Gain Combining (EGC) scheme is considered for MC-CDMA detection. Resul...

We consider the admission control problem in video servers for the retrieval of media data from disk storage. We assume that the I/O bandwidth of the server disk is limited. Given a certain I/O bandwidth, admission control decides whether or not a new client can be accepted without affecting the quality of service promised to the already admitted clients. Assuming variable bit rate (VBR) video ...

In this paper we investigate the transport layer processing intended to improve the communication of multimedia data over wireless and wireline networks. Specifically we consider data striping and thinning techniques, which are applicable to the multipath I multiflow transmission of multimedia (e.g., MPEG4). We also introduce the shufling procedure, which reorders the data at the network edges....

A shaper is a system that stores incoming bits in a bu er and delivers them as early as possible, while forcing the output to be constrained with a given arrival curve. A shaper is time invariant if the tra c constraint is de ned by a xed arrival curve; it is time varying if the condition on the output is given by a time varying tra c contract. This occurs, for example, with renegotiable variab...

This study presents simple and accurate heuristics for determining the equivalent bandwidth for multiplexed variable bit rate (VBR) video sources. The results are based on empirical studies of measurement data of various classes of VBR video sources. They are also validated through extensive simulation. The principal result is that the equivalent bandwidth per source for n independent and ident...

In a system offering on-demand real-time streaming of media files, data striping across an array of disks can improve load balancing, allowing higher disk utilization and increased system throughput. However, it can also cause complete service disruption in the case of a disk failure. Reliability can be improved by adding data redundancy and reserving extra disk bandwidth during normal operatio...

The raising grandness of multimedia diligence has led to the increase in the usage of network resources. For assuring agreed Quality of Service (QoS) and for better network management, thorough analysis of traffic characteristics, modeling and prediction are crucial. In this process, a simple and effective traffic forecasting method which is suitable for time period prediction of MPEG encoded v...

such as interframe coding combined with variable length codes[9] or conditional replenishment[6] [8], that are less efficient than current coding techniques. Other techniques such as subband coding[1] have demonstrated promise for only a few types of services. Another recent study, which provides insights into long run statistics for coded video sequences, used block based intraframe discrete c...

Transparent speech quality has not been achieved at low bit rates, especially at 2.4 kbps and below, which is an area of interest for military and security applications. In this paper, strategies for low bit rate sinusoidal coding are discussed. Previous work in the literature on using metaframes and performing variable bit allocation according to the metaframe type is extended. An optimum meta...