Abstract
Wireless video application and services such as video streaming, video on demand, mobile television, terrestrial and satellite broadcast, form the modem means of communication. Wireless Transmission and delivery of improved mobile video services is mainly influenced by limitation of network resources such as limited bandwidth, power constraints and the prevailing channel characteristic. This research investigates the effects of resource allocation on received video quality of H.264/AVC compatible media streams of diverse content characteristics over resource constrained system. The research aims at formulating and developing efficient novel technologies for adaptation to bridge the constraints imposed by the network environment and enhances robustness of the compressed media stream for improved received video quality. A framework for measuring content motion intensity of media streams is modelled in the first part of the thesis. It forms the basic index for the adaptation process. Quality-Aware Media Bandwidth Adaptation (QABA) is proposed for efficient distribution of shared bandwidth for independent multiple media stream in a bandwidth-constrained system using motion intensity level of the media stream as adaptation index. Secondly, the impact of transmit power constraints on the received video quality is investigated. Adaptive Media Power Allocation Technique (AMPAT) is proposed for improved wireless video services. Content-Aware Power Adaptation is also proposed. It exploits the varying error sensitivity of video packets by adapting the transmission rate per video packet based on the content characteristics and the prevailing channel condition. The effects of channel errors, compression strategy and packetisation structure on received video quality are investigated which aids in the design of adaptation scheme to improve reliability and robustness of media stream over noisy channel. The distinctive feature of the scheme is based on the systematic approach that balances the tradeoffs between the associated error-resilience scheme and the induced overheads. The system performances show that the proposed schemes are more efficient compared to the state-of-the-art for enhancing quality of video services under constrained network resources.