An area-efficient 4/8/16/32-point inverse DCT architecture for UHDTV HEVC decoder

This paper presents a new VLSI architecture for HEVC inverse discrete cosine transform (TDCT). Compared to prior arts, this work reduces hardware cost by 1) reducing computational logic of 1-D IDCTs with a reordered parallel-in serial-out (RPISO) scheme that shares the inputs of the butterfly structure, and 2) reducing the area of the transpose buffer with a cyclic memory organization that achieves 100% I/O utilization of the SRAMs. In the implementation of a unified 4/8/16/32-point IDCT, the proposed schemes demonstrate 35% and 62% reduction of logic and memory costs, respectively. The IDCT implementation can support real-time decoding of 4K×2K 60fps video with a total hardware cost of 357,250um² on 2-D IDCT and 80,988um² on transpose memory in 90nm process.