wpck2d

Compute the packet wavelet transform (details and approximation)

Syntax

out = wpck2d(fimg,wpckname [,'PckParameterName',PckParameterValue]...)

Description

This function computes the (isotropic) wavelet packets of an image given through its Fourier transform fimg. The approximation is calculated from the last scale of 'scales' (recorded inside out.approx) and all details define a volume 'out.details' within each z slide corresponds to a fixed scale.

Input Data

fimg

[COMPLEX MATRIX]: The FFT of the original image.

wpckname

[STRING]: the name of the wavelet/scaling packet to use (see pck_defs subdir for available packets).

scales

[POSITIVE REAL VECTOR]: the vector of scales.

PckParameterValue

[MISC]: the value of a precised packet parameter. See the code of the corresponding wavelet packet for explanations

Output Data

out

[STRUCT] a yawtb object such that:

• out.approx [COMPLEX MATRIX]: contains the approximation at the last scale of the image.
• out.details [COMPLEX VOLUME]: contains the details at each scale (zslides correspond to fixed scale.
• out.scales [POSITIVE REAL VECTOR]: the scales.
• out.extra [LIST]: the extra parameter given to wpckname.
• out.wpckname [STRING]: the name of the packet.
• out.type [STRING]: the name of the mfile, that is wpck2d.

Example(s)

>> mat = theL;
>> tmat = fft2(mat);
>> scales = vect(0.5,10,12);
>> pwav = wpck2d(tmat,'pmexican',scales);
>> figure; imagesc(real(pwav.approx)); // TODO yashow(pwav)!!!
>> figure; imagesc(real(pwav.details(:,:,1)));
>> figure; imagesc(real(pwav.details(:,:,3)));

References

[1] Bruno Torrésani. Analyse Continue par Ondelettes, ???

See Also

iwpck2d pmexican2d theL

Location

discrete/frames/2d/wpck2d.m