Short time Fourier transform
[TFR,T,F] = tfrstft(X) [TFR,T,F] = tfrstft(X, T) [TFR,T,F] = tfrstft(X, T, N) [TFR,T,F] = tfrstft(X, T, N, H [TFR,T,F] = tfrstft(X, T, N, H, TRACE) [TFR,T,F] = tfrstft(...,'plot')
A Nx elements vector: the signal.
a real Nt vector with elements in [1 Nx] : time instant(s) (default: 1:NX).
a positive integer: the number of frequency bins (default:NX). For faster computation N should be a power of 2.
a real vector with odd length: the analysis window, H being normalized so as to be of unit energy. (default : Hamming(N/4)).
if nonzero,the progression of the algorithm is shown (default : 0).
if the last input parameter value is 'plot', tfrqview is called and the time-frequency representation will be plotted.
A complex N by Nt array: the time-frequency representation.
A N vector of normalized frequencies.
sig = [fmconst(64,0.2) ; fmconst(64,0.4)]; tfr = tfrstft(sig); clf; gcf().color_map = jetcolormap(128); subplot(211); grayplot(1:128,1:128,abs(tfr)'); subplot(212); grayplot(1:128,1:128,atan(imag(tfr),real(tfr))'); | ![]() | ![]() |