An Orthogonal 16-point Approximate DCT for Image and Video Compression
  A low-complexity orthogonal multiplierless approximation for the 16-point discrete cosine transform (DCT) was introduced. The proposed method was designed to possess a very low computational cost. A fast algorithm based on matrix factorization was proposed requiring only 60~additions. The proposed architecture outperforms classical and state-of-the-art algorithms when assessed as a tool for image and video compression. Digital VLSI hardware implementations were also proposed being physically realized in FPGA technology and implemented in 45 nm up to synthesis and place-route levels. Additionally, the proposed method was embedded into a high efficiency video coding (HEVC) reference software for actual proof-of-concept. Obtained results show negligible video degradation when compared to Chen DCT algorithm in HEVC. 
T. L. T. da Silveira, F. M. Bayer, R. J. Cintra, S. Kulasekera, A.   Madanayake, A. J. Kozakevicius
cs.IT cs.AR cs.NA math.IT stat.ME