Dynamic Session Control Over IMS for Cross-Layer Optimization of Multi-Stream Video

Cross-layer optimization is an evolutional approach via optimal source and channel resource combinations. It is generally understood that bitstreams can be constructed according to visual importance using multi-stream video in which the base and enhancement layers simultaneously contain visual information of varying importance. In accordance with their importance, radio resources are allocated to each layer for maximal perceptual visual quality using unequal error protection. Nevertheless, a framework for network signalling, which configures each layer using Quality-of-Service (QoS) parameters, has not been presented. This paper proposes a dynamic session control protocol over the IP Multimedia Subsystem (IMS) for network adaptation of multi-stream video where the coding mode can be dynamically changed during the duration of service according to the wireless channel dynamics.