New algorithm for modulated complex lapped transform with symmetrical window function

Qionghai Dai, Xinjian Chen

Abstract: An algorithm for the fast computation of modulated complex lapped transform (MCLT) with symmetrical window function is proposed. The method is based on two discrete cosine transforms (DCTs), two stages of butterfly operations and additional multiplications. The real or imaginary part of the MCLT coefficients can be independently obtained from one of the two blocks of DCT coefficients. The proposed algorithm not only reduces the computational complexity compared with previous algorithms, but also has regular architecture which is suitable for hardware implementations.