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I'm currently working on a project of mine where I have to use stationary wavelet transformation. I found a perfect way to do the transformation using wavelet toolbox of the Matlab. But since it is not free, I need to find a free function to do the exactly same thing SWT function of wavelet toolbox does.

What I Found

I found a Matlab functions package called WaveLab. They have defined a function called FWT_Stat to do Stationary wavelet transformation.

FWT_Stat -- stationary wavelet transform
Usage
 StatWT = FWT_Stat(x,D,qmf) 
Inputs
 x        array of dyadic length n=2^J
 L        degree of coarsest scale
 qmf      orthonormal quadrature mirror filter 
Outputs
 StatWT   stationary wavelet transform table
          formally same data structure as packet table
          log_2(n)-D scales by n elements

Below shows information about SWT function from wavelet toolbox.

SWC = swt(X,N,'wname') computes the stationary wavelet decomposition of the signal X at level N, using 'wname'.

Problem

FWT_Stat function asks for 3 parameters and final parameter is orthonormal quadrature mirror filter.But I couldn't find a way to add haar filter as the input for 3rd parameter .If I used SWT function from wavelet toolbox, all I have to do is add wavelet name (e.g: harr) instead of wname and swt function take care of all other things.

So my problem is, how can I add haar filter as the 3rd parameter for FWT_stat function on Matlab without Wavelet toolbox.

Or, Is there any alternative function (which is free) to do the exact same thing as SWT function from wavelet toolbox?

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I found an answer to this problem and hope to share it here.

Luckily there is another Matlab function call "MakeONFilter" which included in WaveLab package. That function can use to make a filter which can use as the input for FWT_Stat function.

E.g:

haarF = MakeONFilter('Haar');
FWT_Stat(x,D,haarF);
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