This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English version of the page.

Note: This page has been translated by MathWorks. Please click here
To view all translated materials including this page, select Japan from the country navigator on the bottom of this page.


Fejer-Korovkin wavelet filters


Lo = fejerkorovkin(wname)



Lo = fejerkorovkin(wname) returns the Fejer-Korovkin scaling filter specified by wname. Valid entries for wname are 'fk4', 'fk6', 'fk8', 'fk14', 'fk18', and 'fk22'. For information on the Fejer–Korovkin filters, see Nielson[1].


collapse all

Construct and plot the Fejer-Korovkin (14) scaling function and wavelet.

Obtain the Fejer-Korovkin scaling filter and display its 14 coefficients.

Lo = fejerkorovkin('fk14')
Lo = 

  Columns 1 through 7

    0.2604    0.6869    0.6116    0.0514   -0.2456   -0.0486    0.1243

  Columns 8 through 14

    0.0222   -0.0640   -0.0051    0.0298   -0.0033   -0.0093    0.0035

Use the scaling filter to obtain the wavelet filter and display its wavelet filter coefficients.

Hi = qmf(Lo)
Hi = 

  Columns 1 through 7

    0.0035    0.0093   -0.0033   -0.0298   -0.0051    0.0640    0.0222

  Columns 8 through 14

   -0.1243   -0.0486    0.2456    0.0514   -0.6116    0.6869   -0.2604

wavefun provides an efficient way to construct and plot the scaling function and wavelet.

[phi,psi,xval] = wavefun('fk14');
title('Scaling Function')

Input Arguments

collapse all

Filter name, specified as a character vector. The numeric value in each name is the number of Fejer-Korovkin filter coefficients.

Output Arguments

collapse all

Scaling filter, returned as a vector.


[1] Nielsen, M. "On the construction and frequency localization of finite orthogonal quadrature filters." Journal of Approximation Theory. Vol. 108, pp. 36–52.

See Also

| |

Introduced in R2015b

Was this topic helpful?