TR-IIS-05-017    Fulltext


Aggressive Traffic Smoothing for Online Delivery

Jeng-Wei Lin, Ray-I Chang, Jan-Ming Ho, Feipei Lai

Abstract

Traffic smoothing is an efficient means to reduce the bandwidth requirement for transmitting a VBR video. Several traffic smoothing algorithms have been presented to offline compute the transmission schedule for a prerecorded video. For live video applications, Sen et al. present an online algorithm referred to as SLWIN(k) to compute the transmission schedule on the fly. SLWIN(k) looks ahead W frames to compute the transmission schedule for the next k frametimes, where k≤W. Note that W is upper bounded by the initial delay of the transmission schedule. The time complexity of SLWIN(k) is O(W*N/k) for an N frame live video. In this paper, we present an O(N) online traffic smoothing algorithm denoted as ATS (Aggressive Traffic Smoothing). ATS aggressively works ahead to transmit more data as early as possible for reducing the peak rate of the bandwidth requirement. We compare the performance of our algorithm with SLWIN(k) based on several benchmark video clips. Experiments show that ATS further reduces the bandwidth requirement, especially for interactive applications in which the initial delays are small.

 

Keywords: Multimedia Streaming, Online Delivery, Traffic Smoothing, Live Video