Benefits and costs of scalable video coding for internet streaming

Benefits and costs of scalable hybrid video coding techniques are analyzed with respect to internet streaming. Temporal, spatial, amplitude scalability, and combinations as described in MPEG-4 are considered. Benefits are a reduction of the server storage capacity, a reduction of the netload for multicast delivery and a graceful degradation in case of transmission errors. Costs are ail increasing netload for unicast delivery and ail increasing computational expense in the decoder. The result of an evaluation shows that temporal scalability has minimum costs among all analyzed techniques. It increases the netload for unicast only marginally with no additional Computational expense in the decoder. Temporal scalability provides a reduction of the server storage capacity and netload for multicast by about 30%, and two steps of graceful degradation. All other known standardized and nonstandardized techniques of spatial and amplitude scalability are associated with costs that appear too high to be attractive for internet streaming. Therefore, only temporal scalability is used at the present. Some of the scalable video coding techniques may become of interest for other applications where the investigated costs are less relevant. (c) 2005 Elsevier Inc. All rights reserved.