Logarithmic frequency representation has an important role in many
audio and acoustic signal processing applications.
This article presents a methodology for frequency-warped signal
processing where the frequency representation is logarithmic above a
certain limit frequency. It is demonstrated how this approach
can be used with FFT or linear prediction to perform non-parametric,
or parametric constant-Q spectrum analysis, respectively. The
benefits of the use of logarithmic frequency representation are
demonstrated with harmonic signals. It is also discussed how linear
filters can be designed and implemented directly on a logarithmic
frequency scale.
