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wfilters

Wavelet filters

Syntax

Description

[Lo_D,Hi_D,Lo_R,Hi_R] = wfilters('wname') computes four filters associated with the orthogonal or biorthogonal wavelet named in the string 'wname'.

The four output filters are

Available orthogonal or biorthogonal wavelet names 'wname' are listed in the table below.

Wavelet Families
Wavelets
Daubechies
'db1' or 'haar', 'db2', ... ,'db10', ... , 'db45'
Coiflets
'coif1', ... , 'coif5'
Symlets
'sym2', ... , 'sym8', ... ,'sym45'
Discrete Meyer
'dmey'
Biorthogonal
'bior1.1', 'bior1.3', 'bior1.5'
'bior2.2', 'bior2.4', 'bior2.6', 'bior2.8'
'bior3.1', 'bior3.3', 'bior3.5', 'bior3.7'
'bior3.9', 'bior4.4', 'bior5.5', 'bior6.8'
Reverse Biorthogonal
'rbio1.1', 'rbio1.3', 'rbio1.5'
'rbio2.2', 'rbio2.4', 'rbio2.6', 'rbio2.8'
'rbio3.1', 'rbio3.3', 'rbio3.5', 'rbio3.7'
'rbio3.9', 'rbio4.4', 'rbio5.5', 'rbio6.8'

[F1,F2] = wfilters('wname','type') returns the following filters:

Lo_D and Hi_D
(Decomposition filters)
If 'type' = 'd'
Lo_R and Hi_R
(Reconstruction filters)
If 'type' = 'r'
Lo_D and Lo_R
(Low-pass filters)
If 'type' = 'l'
Hi_D and Hi_R
(High-pass filters)
If 'type' = 'h'

Examples

See Also
biorfilt, orthfilt, waveinfo

References

Daubechies, I. (1992), Ten lectures on wavelets, CBMS-NSF conference series in applied mathematics. SIAM Ed.

Mallat, S. (1989), "A theory for multiresolution signal decomposition: the wavelet representation," IEEE Pattern Anal. and Machine Intell., vol. 11, no. 7, pp. 674-693.


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