Scilab Wavelet Toolbox Function
Last update : Feburary 2006

orthfilt - orthorgonal filter groups obtaining

Calling Sequence

[Lo_D,Hi_D,Lo_R,Hi_R]=orthfilt(lo_r)

Parameters

Description

This function obtains the filter groups representing the fast wavelet cascade algorithm of Lowpass decompostion filter, Hipass decomposition filter, Lowpass reconstruction filter and Hipass reconstruction filter. Please note only daubechies and some particular wavelets allow this kind of function. Others may use other function rather than orthfilt.

Examples

-->lo_r=wave('db2');
-->[Lo_D,Hi_D,Lo_R,Hi_R]=orthfilt(lo_r);

-->Lo_D
 Lo_D  =

! - 0.1294095    0.2241439    0.8365163    0.4829629 !

-->Hi_D
 Hi_D  =

!   0.4829629  - 0.8365163    0.2241439    0.1294095 !

-->Lo_R
 Lo_R  =

!   0.4829629    0.8365163    0.2241439  - 0.1294095 !

-->Hi_R
 Hi_R  =

!   0.1294095    0.2241439  - 0.8365163    0.4829629 !

-->[Lo_D,Hi_D,Lo_R,Hi_R]=orthfilt(3);
Input should be long enough!

-->[Lo_D,Hi_D,Lo_R,Hi_R]=orthfilt(rand(2,2));
Input should be vectors rather than matrixes!

  

See Also

wave