Digital video coding technologies are currently of widespread use within many heterogeneous communication services that are supported by multimodal devices and systems. With these services and systems comes the need of using video Codecs and transcoders that can perform optimally under multiple objectives and varying constraints, related mostly to rate, distortion, memory usage, complexity, delay, packet loss and battery power.
The research presented in this thesis proposes a generalised multi-objective optimization framework that can optimize the performance of a H.264/AVC Codec and a H.264/AVC based multi-architecture transcoding system.
In the first part of this research, an optimization scheme is designed to determine the optimum coding parameters for a H.264/AVC video Codec in a memory and bandwidth constrained environment, which minimises Codec complexity and distortion. The same optimization framework is later extended by including delay as an additional constraint. The second part of the optimization work presented in this thesis focuses on developing an optimal H.264/AVC transcoding system that is capable of selecting a transcoding method from a multitude of different alternatives, subject to available system resources and client requirements of bitrate and quality of the requested video. Both parts of the research have been evaluated via rigorous experimental analysis, leading to optimal solutions.
This thesis is confidential until 31st December 2021. A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.