compressogram.m

老外写的小波变换的工具箱

function CompressoGram(Sig,QMF_Filter)
% CompressoGram -- compare compress abilities of four transforms
%

% Haar Transform
	HaarQMF = MakeONFilter('Haar');
	hSig = FWT_PO(Sig,1,HaarQMF);
	epsilon = 1.e-16;  
	ehSig = reverse(cumsum(sort(hSig.^2)))/sum(hSig.^2) + epsilon;
% Cosine Transform
	fSig = dct_iv(Sig); 
	efSig = reverse(cumsum(sort(fSig.^2)))/sum(fSig.^2) + epsilon;
% Wavelet Transform
	wSig = FWT_PO(Sig,5,QMF_Filter);
	ewSig = reverse(cumsum(sort(wSig.^2)))/sum(wSig.^2) + epsilon;
	i = 1:length(ewSig);
%
	LockAxes([0 length(ewSig)/2 -8 0]);
	xlabel('n')
	ylabel('Log(c_n)')
	plot(i,log(ewSig),'-');
	plot(i,log(ehSig),'+');
	plot(i, log(efSig),'.')
	UnlockAxes
	
%	Revision History
%		09/29/99	DLD	   added epsilon to avoid log(0)
%       10/1/05     AM     Changing the name of the variable QMF


    
    
    
 
 
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