Title: Video Smoothing of Streams Aggregate with Bandwidth Constraints
Authors: Pietro Camarda, Cataldo Guaragnella, Domenico Striccoli
Abstract: Compressed variable bit rate (VBR) video transmission is assuming a growing importance in the telecommunication world. High data rate variability of compressed video over multiple time scales makes an efficient bandwidth resource utilization difficult to obtain. Smoothing techniques is one of the approaches developed to face this problem. Various smoothing algorithms have been proposed, that exploit client buffers thus reducing the peak rate and high rate variability by efficiently scheduling the video data to be transmitted over the network. The novel smoothing algorithm proposed in this paper, which represents a significant improvements over existing methods, performs data scheduling both for a single stream and stream aggregations, by taking into account available bandwidth constraints. It modifies, whenever possible, the smoothing schedule in such a way to eliminate frame losses due to available bandwidth limitations. This technique can be applied to any smoothing algorithm already present in literature and can be usefully exploited to minimize losses in multiplexed stream scenarios, like Terrestrial Digital Video Broadcasting (DVB-T), where a specific known available bandwidth must be shared by several multimedia flows. The developed algorithm has been exploited for smoothing stored video, although it can be quite easily adapted also for real time smoothing. The obtained numerical results, compared with the MVBA, another smoothing algorithm, already presented and discussed in literature, show the effectiveness of the proposed algorithm, in term of lost video frames, for different multiplexed scenarios.