A hierarchical scheme of flexible macroblock ordering for ROI based H.264/AVC video coding

A hierarchical Flexible Macroblock Ordering (FMO) scheme is proposed in this paper, which can be combined well with Region Of Interest (ROI) based error resilient coding schemes while much fewer header bits are added than the existing FMO schemes in H.264/AVC standard. By defining a new FMO type with small modification of the syntax of H.264/AVC standard, the proposed FMO scheme can not only encode the ROI region and the non-ROI region in different slice groups, but also further divide the ROI region into several sub slice groups. It achieves a better tradeoff between video compression efficiency and error resilient performance by the hierarchical FMO scheme when the video data is transmitted over error-prone networks based on our experiments.