Convention Paper
Method for Estimating Magnitude and Phase in the MDCT Domain
AES Convention 116 · Paper 6091 · May 2004
Abstract
This paper introduces a method for estimating the magnitude and phase responses in audio coders which employ the Modified Discrete Cosine Transform (MDCT). This technique computes magnitude and phase estimates at the decoder using two pieces of information: 1) MDCT coefficients transmitted by the encoder; 2) an estimate of the Modified Discrete Sine Transform (MDST) computed from the transmitted MDCT coefficients. In this manner, approximate magnitude and phase estimates suitable for use with some decoder-oriented signal processing techniques can be constructed entirely from MDCT coefficients available at the decoder. We show that these approximate methods are less computationally intensive than exact methods, and we compare the performance of the approximate methods to exact methods.
