Efficient hardware architecture for direct 2D DCT computation and its FPGA implementation

Abstract

In this paper, we propose a low complexity architecture for direct 2D-DCT computation. The architecture will transform the pixels from spatial to spectral domain with the required quality constraints of the compression standards. In our previous works we introduced a new fast 2D_DCT with low computations: only 40 additions are used and no multiplications are needed. Based on that algorithm we developed in this work a new architecture to achieve the computations of the 2D DCT directly without using any transposition memory. We defined Sk functions blocks to build the 2D DCT architecture. The Sk block perform 8 function depending on the control signals of the system. The number of additions/subtractions used is 63, but no multiplication or memory transposition is needed. The architecture is suitable for usage with statistical rules to predict the zero quantized coefficients, which can considerably reduce the number of computation. We implemented the design using an FPGA Cyclone 3. The design can reach up to 244 MHz and uses 1188 logic elements, and it respect the real time video requirements.