A pipelined architecture for 4×4 intra frame mode decision in the high efficiency video coding

Mode decision in High Efficient Video Coding (HEVC) is occupied more than half of the computational complexity in intra frame coding. Block size of 4×4 is the most frequently used block in HM. In this paper, we proposed a pipelined architecture for the 4×4 intra frame mode decision in HEVC to improve the computational capability. This novel architecture consists of six-stage pipelines, and each of the pipelines can be accomplished within 24 clock cycles. In the pipeline of prediction procedure, we proposed a folded project-skip architecture for prediction. It can save the processing latency and the registers considerably. We also proposed a simplified CAVLC with low complexity in the pipeline of bits estimation procedure. The architecture for mode decision has been evaluated with TSMC 0.13μm CMOS technology. Synthesized results show that the proposed architecture only needs 99K logic gates for modes decision and can run at 165 MHz operation frequency.