Bit Allocation for Spatial Scalability in H.264/AVC

The authors propose a model-based spatial layer bit allocation algorithm for H.264/SVC in this paper. The spatial scalability of H.264/SVC is achieved by a multi-layer approach, where an enhancement layer is bound by the dependency on its preceding layers. The inter-layer dependency is decoupled in their analysis by a careful examination of the signal flow in the H.264/SVC encoder. They show that the Rate and the Distortion (RD) characteristics of a dependent layer can be represented by a number of independent functions with a Group Of Pictures (GOP) as a basic coding unit. Finally, a low complexity spatial layer bit allocation scheme is developed using the proposed GOP-based RD models.