Real-time video communication over a packet switching network is subject to losses and errors. In few networking environment, a partially reliable transport service based on error control by retransmission is a possible option. We propose a retransmission-based correction scheme which is driven by the time remaining for the data delivery and also by the importance of artifacts the data loss produces in the reconstructed video. This scheme is applied to continuous MPEG video packet streams. Experimental results show that the picture quality of MPEG video is degraded more gracefully in the presence of network errors, and those with a low cost on network bandwidth. In addition, the best QoS policy to use the partially reliable transport service is highlighted.