Hilbert-Huang Transform

The function plot_hht is a realization of the Hilbert-Huang transform (HHT). The HHT decomposes a signal into intrinsic mode functions (or IMFs), and obtain the instantaneous frequency data. It is designed to work well for data that are nonstationary and nonlinear (http://en.wikipedia.org/wiki/Hilbert-Huang_Transform). Learn more about the HHT from the attached pdf.
The function plot_hht is best used with spsnip_gui available at http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=11002&objectType=FILE.

Essential files: plot_hht.m, emd.m, findpeaks.m
Accompanying files: Hum.wav, HHT.pdf