Channel Change Delay in IPTV Systems
10 January 2009
MPEG-based compression schemes and multicast-based nature of IPTV deployments result in channel change delay. Solutions to reduce this delay have been proposed in the literature and also the commercial deployments. In this paper, we present an analysis of channel change delay in multicast-based IPTV systems. As video encoding parameters, more specifically the frequency of the intra-coded (I-) frames, have major impact over the channel change delay, we also investigate how different intra-coded frame frequency affects the channel change delay. In the second part part of the paper, we evaluate the bandwidth penalty of using more frequent I-frame to reduce the channel change delay. Our results show that that, average channel change delay can be reduced to around 300 msec with acceptable bandwidth penalties without using an explicit channel change acceleration mechanisms. When the requirement is more strict, an explicit channel change acceleration mechanism will be necessary.