A Novel DCT-Based Algorithm for Computing the Modulated Complex Lapped Transform

Xinjian Chen, Qionghai Dai

Abstract: In this correspondence, we propose a novel discrete cosine transform (DCT)-based algorithm for the fast computation of the modulated complex lapped transform (MCLT), which we have previously proposed. The method is mainly based on two DCTs and two stages of butterfly operations. For a length-M MCLT, the proposed algorithm requires only Mlog <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> M multiplications for the sine window and Mlog <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> M+2M multiplications for any other window function. Thus, the multiplicative complexity of the proposed algorithm is superior to any other previous algorithm, without any penalty on the total number of multiplications and additions