An optimized FPGA design of inverse quantization and transform for HEVC decoding blocks and validation in an SW/HW environment

Abstract

This paper presents an optimized hardware architecture of the inverse quantization and the inverse transform(IQ/IT) for a high-efficiency video coding (HEVC) decoder. Our highly parallel and pipelined architecture was designedto support all HEVC Transform Unit (TU) sizes: 4 × 4, 8 × 8, 16 × 16, and 32 × 32. The IQ/IT was described in theVHSIC hardware description language and synthesized to Xilinx XC7Z020 field-programmable gate array (FPGA) and toTSMC 180 nm standard-cell library. The throughput of the hardware architecture reached in the worst case a processingrate of up to 1080 p at 33 fps at 146 MHz and 1080 p at 25 fps at 110 MHz when mapped to FPGA and standardcells, respectively. The validation of our architecture was conducted on the ZC702 platform using a Software/Hardware(SW/HW) enviro nment in order to evaluate different implementation methods (SW and SW/HW) in terms of powerconsumption and run-time. The experimental results demonstrate that the SW/HW accelerations were enhanced bymore than 70% in terms of the run-time speed relative to the SW solution. Besides, the power consumption of theSW/HW designs was reduced by nearly 60% compared with the SW case.