A fast 8×8 IDCT algorithm for HEVC

As an approximation to the Discrete Cosine Transform (DCT), Integer Cosine Transform (ICT) is widely used in latest video coding standards, such as H.264/AVC, VC-1 and AVS. High Efficiency Video Coding (HEVC), the next generation of video compression standard, adopts 4/8/16/32 integer transform. Since the size of matrices themselves and the numerical magnitude of matrix elements are very large, HEVC transform suffers from huge computational complexity. To alleviate this problem, we proposed a fast algorithm for order-8 integer transform for HEVC. This algorithm has 66% less multiplications and 46% less additions than direct method and saves 60% area for hardware implementation. It is illustrated by signal-flow graph, which is easy to be translated to hardware or software implementation.