Title :
Fast algorithm for the modulated complex lapped transform
Author :
Malvar, Henrique S.
Author_Institution :
Microsoft Res., Redmond, WA, USA
Abstract :
A new algorithm for fast computation of the modulated complex lapped transform (MCLT) is presented. For a length-M MCLT, the algorithm is based on computing a length-2M fast Fourier transform plus M butterfly-like stages, without data shuffling. That reduces the number of operations and memory accesses needed to compute the MCLT when compared to previous algorithms. Compared to the original type-4 discrete-cosine-transform-based algorithm, an implementation of the new algorithm leads to 25% faster execution.
Keywords :
audio signal processing; computational complexity; fast Fourier transforms; MCLT; audio processing; butterfly-like stages; length-2M fast Fourier transform; memory accesses; modulated complex lapped transform; Computational complexity; Discrete Fourier transforms; Discrete transforms; Encoding; Fast Fourier transforms; Filter bank; Frequency; Noise reduction; Time domain analysis;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2002.806700
