PCR-assist CBR for delivering pre-recorded MPEG-2 transport streams

Abstract

Transmitting compressed variable bit-rate (VBR) video with a traditional constant bit-rate (CBR) service for continuous playback requires a large buffer on the viewer's side. In this paper, we study a new CBR transmission scheme which employs the program clock references (PCR) that are embedded in the MPEG-2 transport streams to reduce the buffer requirement. The scheme is called "PCR-assist CBR" (PCBR). The PCBR scheme uses PCRs to examine its transmission regularly. It holds up the transmission if it is ahead of schedule. Based on experimental results with video traces, the PCBR scheme reduces the buffer requirement at the cost of a higher transmission rate.