Video Quality Protection Strategies for HDTV in the Presence of Buffer Overflow

We investigate the impact of Forward Error Correction (FEC) and retransmissions on the video quality of packetized HDTV video flows with possible buffer overflow at the ingress node of the video network. The use of protection is a mixed blessing. On the one hand, it increases the packet rate associated with each video flow (due to overhead), which results in a higher buffer overflow probability. On the other hand, protection allows for the recovery of lost packets, which alleviates the problem of buffer overflow. It turns out that the overall impact of FEC and retransmission is very beneficial for the video quality. Moreover, retransmissions clearly outperform FEC, and can ensure HDTV video quality up to loads at the ingress node close to one.