Cost-effective scenarios of CABAC in H.264/AVC codec

Abstract

Context-based Adaptive Binary Arithmetic Coding (CABAC) has been adopted for the Main and higher profiles of the H.264/AVC codec. Several performance complexity analyses have been conducted, and CABAC hardware designs have been proposed. However, no standard performance complexity method has been reported, and no cost-effective scenarios for CABAC versus its predecessor Context-based Adaptive Variable Length Coder (CAVLC) have been identified. In this paper, we propose a method using an aggregate indicator, the Performance Complexity Index (PCI), for evaluating the cost-effectiveness of trading complexity for performance. With the proposed PCI, our analyses are confirmed as follows. Simulation results at the encoder, using a specific architecture, show that it is cost-effective to use CABAC for encoding under RDO-off (Rate-Distortion Optimization) mode.