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Wavelet and scaling filters

returns the Fourier transform of the scaling filter for the 2-D wavelet scattering
framework, `phif`

= filterbank(`sf`

)`sf`

. `phif`

is a single or
double-precision matrix depending on the value of the `Precision`

property
of the scattering framework. `phif`

has dimensions
*M*-by-*N*, where *M* and
*N* are the padded row and column sizes of the scattering framework.

`[`

returns the Fourier transforms for the wavelet filters in `phif`

,`psifilters`

] = filterbank(`sf`

)`psifilters`

.
`psifilters`

is an *Nfb*-by-1 cell array, where
*Nfb* is the number of filter banks in the scattering framework. Each
element of `psifilters`

is a 3-D array. The 3-D arrays are
*M*-by-*N*-by-*L*, where
*M* and *N* are the padded row and column sizes of the
wavelet filters and *L* is the number of wavelet filters for each filter
bank. The wavelet filters are ordered by increasing scale with
`NumRotations`

wavelet filters for each scale. Within a scale, the
wavelet filters are ordered by rotation angle.

`[`

returns the center spatial frequencies for the wavelet filters in
`phif`

,`psifilters`

,`f`

] = filterbank(`sf`

)`psifilters`

. `f`

is an *Nfb*-by-1
cell array, where *Nfb* is the number of filter banks in
`sf`

. The *j*th element of `f`

contains the center frequencies for the *j*th wavelet filter bank in
`psifilters`

. Each element of `f`

is a
*L*-by-2 matrix with each row containing the center frequencies of the
corresponding *L*th wavelet.

`[`

returns the filter parameters for the 2-D scattering framework.
`phif`

,`psifilters`

,`f`

,`filterparams`

] = filterbank(`sf`

)`filterparams`

is an *Nfb*-by-1 cell array of
MATLAB^{®} tables, where the *j*th element of
`filterparams`

is a MATLAB table containing the filter parameters for the *j*th filter
bank

`[___] = filterbank(`

returns the desired outputs for the filter banks specified in `sf`

,`fb`

)`fb`

.
`fb`

is a scalar or vector of integers between 1 and
`numfilterbanks(sf)`

inclusive. If `fb`

is a scalar,
`psifilters`

is an
*M*-by-*N*-by-*L* matrix, and
`filterparams`

is a MATLAB table.