A 250MHz optimized distributed architecture of 2D 8x8 DCT

Discrete cosine transform (DCT) plays an important role in image and video compression, but computing a two-dimensional (2D) DCT, a large number of multiplications and additions are required in a direct approach. Multiplications, which are the most time-consuming and expensive operations in simple processor, can be completely avoided in our proposed architecture for multiple channel real-time image compression. In this paper, a compressed distributed arithmetic architecture for 2D 8times8 DCT is presented, which offers high speed and small area. The basic architecture consists of a ID row DCT followed by a transpose register array and another ID column DCT, in which an 8-input ID DCT structure only requires 15 adders to build a compressed adder matrix and no ROM is needed. Compared with other architectures available, it has a great improvement on computing speed and reducing area.