makewaveletpacket.sci

小波分解源代码

function wavepkt = MakeWaveletPacket(d,b,k,Family,par,n)
// MakeWaveletPacket -- Make periodized orthogonal wavelet packet
//  Usage
//    wavepkt = MakeWaveletPacket(d,b,k[,Family,par,n])
//    wavepkt = MakeWaveletPacket(d,b,k,qmf[,n])
//  Inputs
//    d,b,k     1-d packet index
//    Family    Wavelet Family name  (Default 'Symmlet')
//    par       Family Parameter     (Default 8)
//    qmf       quadrature mirror filter
//    n         signal length        (>> 2^d)
//  Outputs
//    wavepkt   1-d signal; the requested wavelet packet
//
//  Description
//    This function returns the wavelet packet basis element
//    corresponding to position (d,b,k) in the WP table.
//
//  See Also
//     WPAnalysis, WPSynthesis
//
//  Copyright Aldo I Maalouf

  [lhs,rhs]=argn();
	if rhs < 4,
	   Family = 'Symmlet';
	   par    = 8;
	end

	if ischar(Family)
		qmf = MakeONFilter(Family,par);
		maxnarg = 6;
		if rhs < maxnarg,
		   n = 2^(d+5);
		end	
	else
		qmf = Family;
		maxnarg = 5;
		if rhs < maxnarg,
		   n = 2^(d+5);
		else
			n = par;
		end
	end

	L   = d+1;
	wp  = zeros(n,L);
	wp  = WPImpulse(wp,d,b,k,qmf);
	wavepkt = wp(:,1)';
	endfunction