Application of Nonuniform Sampling to Error Concealment

Abstract

Despite the huge advances in the communication networks industry, the new breed of multimedia applications and services is pushing the existing networks to their bandwidth limits. In ATM networks, the bandwidth is dynamically allocated according to the requirements of the transmitted services. ATM cells are usually stored in the switch buffers before being routed to the destination node. In practice, ATM buffers have limited sizes and they may overflow in the case of congested traffic. When ATM buffers overflow, low priority cells are dropped to ensure transmission continuity of the service using the rest of the cells. Also, ATM cells may be mis-routed due to non-correctable bit errors in the routing information of the cells. When ATM cells carry in their payload a compressed image, cell losses due to buffer overflow or cell mis-routing can cause major degradation in the quality of the transported image. This degradation is usually in the form of corrupted blocks or macroblocks. Losing one cell may result into the loss of several blocks of the compressed image.