An improved scaled DCT architecture

Abstract

This paper presents an efficient architecture for computing the eight-point 1D scaled DCT (discrete cosine transform) with a new algorithm based on a selected Loeffler DCT scheme whose multiplications are placed in the last stage. The proposed DCT architecture does not require any scaling compensation in the computation. Furthermore, a multiplication approximation method is developed, which is more efficient than traditional CORDIC (coordinate rotation digital computer)-based algorithms. Compared to the latest work (Sun et al., 2007), the proposed approach can save 14% addition operations for the same precision requirement and the path delay can be significantly reduced as well.