wt04fig13.m

斯坦福大学的小波的工具箱 比matlab自带的工具箱更完善

%CAPTION
fprintf('\n');
disp('Figure 4.13')
disp('Window 1: The top signal is a sum of two linear chirps.')
disp('The bottom image is the spectrogram. ')
disp('Window 2: Ridges calculated from the spectrogram. ')
disp('Enlarge the window to improve the visualization of ridges.')

close all;
Name = 'LinChirps';
N = 1024;
	f = MakeSignal(Name,N);
	window = 50;

	
% axes handles	
	delta = 1/15;
	unit = (1-3*delta)/3;
	h3 = [delta delta 1-2*delta 2*unit];
	h2 = [delta 2*(unit+delta) 1-2*delta unit];
	h1 = [delta 4*unit+3*delta 1-2*delta unit];
	h0 = [delta delta 1-2*delta 1-2*delta];
	
figure(1);clf
       set(gcf, 'NumberTitle','off', 'Name','Window 1')
	axes('position',h2);
		plot(f);
		axis([1 N min(f) max(f)]);
	axes('position',h3);
  		specgm = WindowFT(f,window,1,'Gaussian');	


figure(2);clf
       set(gcf, 'NumberTitle','off', 'Name','Window 2')
	axes('position',h3);
		ridges = Ridge_WindowFT(specgm);
		xtix   = linspace(0,N,N);
		sz = size(ridges);
		ytix = linspace(0,N/2,sz(2));
		imagesc(xtix,ytix,256.*ridges(1:N/2,:));
		axis('xy')
		xlabel('')
		ylabel('Frequency')
		colormap(1-gray(256));

% Written by Maureen Clerc and Jerome Kalifa, 1997
% [e-mail], [e-mail]
    
    
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% Part of WaveLab Version 802
% Built Sunday, October 3, 1999 8:52:27 AM
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% For Copying permissions see COPYING.m
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