pqmf

Synopsis

Description

pqmf designs a Quadratic Mirror filter for wavelet transform. This filter can then be used with operator pdwt.

Information stored in the filter is the name of the filter, and the set of lowpass filter coefficients to allows the calculus of the dyadic wavelet decomposition.

Parameters

• name specifies the name of the filter among 7 available filters.
• order then specifies the order of the filter.
  • haar: 1
  • beylkin: 1
  • coiflet: 1, 2, 3, 4 ou 5
  • daubechies: 4, 6, 8, 10, 12, 14, 16, 18 ou 20
  • symmlet: 4, 5, 6, 7, 8, 9 ou 10
  • vaidyanathan: 1
  • battle: 1, 3 ou 5

Output

• col_out: a collection that contains the filter coefficients.

Result

Returns SUCCESS or FAILURE.

Examples

Builds a synthetic image (a square) to illustrate the Gibbs phenomenon in wavelets analysis.

   pshapedesign 256 256 0 2 150 150 a.pan
   pqmf daubechies 4 b.pan
   pdwt 1 a.pan b.pan c.pan
   psplitimage c.pan d1.pan d2.pan d3.pan d4.pan
   pthresholding 20 400 d2.pan e2.pan
   pthresholding 20 400 d3.pan e3.pan
   pthresholding 20 400 d4.pan e4.pan
   pmergeimages d1.pan e2.pan e3.pan e4.pan f.pan
   pidwt 1 f.pan b.pan out.pan

See also

C++ prototype

Version française

Génération d'un filtre QMF pour la transformée en ondelette.