Tool based on time frequency methods
TimeFrequencyTool(signal,freq_sampling,options)
a real vector, the signal to be analyzed.
a positive scalar, the sampling frequency of the signal.
A struct with possible fields:
"sp"
(spectrogram),
"spwv"
(smoothed pseudo
Wigner-Ville), ""zam"
(Zao-Atlas-Marks time-frequency distribution),
"bj"
(sBorn-Jordan time-frequency
distribution),"pseudocolor"
(2D display done
by grayplot ), "3d"
(3D display
done by plot3d1)"jet"
(jetcolormap used) or
"gray"
(reverted graycolormap used).This tool can be used to explore the spectrum and the frequency evolution of a signal using various time frequency methods and various visualization methods.
datafile = path=cardiovascularpath()+"demos/DATA/apnee_spont"; d=read(datafile,-1,7); freq_sampling=4; RR=d(:,1); Vt=d(:,5); f1=scf(100001);clf;f1.figure_position=[0 0];f1.figure_size=[524 514]; f1.figure_name="TimeFrequency RR apnea"; TimeFrequencyTool(RR,freq_sampling) f2=scf(100002);clf;f2.figure_position=[450 0];f2.figure_size=[524 514]; f2.figure_name="TimeFrequency Vt apnea"; TimeFrequencyTool(Vt,freq_sampling) | ![]() | ![]() |
Mainly based on the tome frequency toolbox stftb