A novel pipeline architecture for H.264/AVC CABAC decoder

We present a high-throughput and low-cost context adaptive binary arithmetic (CABAC) decoder for H.264/AVC. Since the CABAC decoder has strong data dependency while decoding a plurality of bins, we propose a novel pipeline architecture to speed up this operation. Based on different types of syntax elements, two approaches to improve throughput are proposed. In addition, we re-arrange the context models in memory by applying two principles in order to reduce the usage of memory space and to lower the frequency in memory access. The proposed CABAC decoder is already integrated in a H.264 decoder and is able to achieve real-time decoding for H.264/AVC high profile HD level 4.1. The implemented design can operate at 250 MHz with 35.6 k gate count under 0.18 mum silicon technology.