High-level synthesis implementation of HEVC 2-D DCT/DST on FPGA

This paper presents the first known high-level synthesis (HLS) implementation of integer discrete cosine transform (DCT) and discrete sine transform (DST) for High Efficiency Video Coding (HEVC). The proposed approach implements these 2-D transforms by two successive 1-D transforms using a well-known row-column and Even-Odd decomposition techniques. Altogether, the proposed architecture is composed of a 4-point DCT/DST unit for the smallest transform blocks (TBs), an 8/16/32-point DCT unit for the other TBs, and a transpose memory for intermediate results. On Arria II FPGA, the low-cost variant of the proposed architecture is able to support encoding of 1080p format at 60 fps and at the cost of 10.0 kALUTs and 216 DSP blocks. The respective figures for the proposed high-speed variant are 2160p at 30 fps with 13.9 kALUTs and 344 DSP blocks. These cost-performance characteristics outperform respective non-HLS approaches on FPGA.