updyad_sbs.sci

小波分解源代码

function x = UpDyad_SBS(beta,alpha,qmf,dqmf)
// UpDyad_SBS -- Symmetric Upsampling operator
//  Usage
//    x = UpDyad_SBS(beta,alpha,qmf,dqmf)
//  Inputs
//   beta  coarse coefficients
//   alpha fine coefficients
//    qmf   quadrature mirror filter
//   dqmf  dual quadrature mirror filter
//  Outputs
//   x     1-d signal at fine scale
// See Also
//   DownDyad_SBS, IWT_SBS
//
//  Copyright Aldo I Maalouf
//
//        oddf = (rem(length(qmf),2)==1);
 	        oddf = ~(qmf(1)==0 & qmf(length(qmf))~=0);
 	        oddx = (length(beta) ~= length(alpha));
 	       
 	        L = length(beta)+length(alpha);
 	
 	        if oddf then
 	          if oddx then
 	            ebeta = extend(beta,1,1);
 	            ealpha = extend(alpha,2,2);
 	          else
 	            ebeta = extend(beta,2,1);
 	            ealpha = extend(alpha,1,2);
 	          end
 	        else
 	          if oddx then
 	            ebeta = extend(beta,1,2);
 	            ealpha = [alpha 0 -reverse(alpha)];
 	          else
 	             ebeta = extend(beta,2,2);
 	             ealpha = [alpha -reverse(alpha)];
 	          end
 	        end
 	
 	        coarse = UpDyadLo_PBS(ebeta,dqmf);
 	        fine = UpDyadHi_PBS(ealpha,qmf);
 	        x = coarse + fine;
 	        x = x(1:L);
 	        
endfunction