Dual tree discrete wavelet transform filter generation.

USAGE:

wavDTWTFilters( bio = ``nearsyma", qshift = ``a" )

DESCRIPTION:

Calculates the wavelet and scaling filter coefficients for a dual tree wavelet transform (DTWT). There are two sets that are specified: (1) a biorthogonal set used only for level one of the DTWT and (2) an even-length, quarter-sample shift (Q-Shift) filter set used for decomposition levels greater than one.

OPTIONAL ARGUMENTS:

biorthogonal
A character string denoting the level one biorthogonal filter type. Supported types are ``antonini", ``legall", ``nearsyma", and ``nearsymb". Default: ``nearsyma".
qshift
A character string denoting the Q-Shift filter type used for levels greater than one. Supported types are ``a", ``b", ``c", and ``d". Default: ``a".

VALUE:

result
An object of class WaveletKingsbury.

REFERENCES:

(1) N. G. Kingsbury, ``The dual-tree complex wavelet transform: a new efficient tool for image restoration and enhancement'', Proc. EUSIPCO 98, Rhodes, Sept. 1998.

(2) N. G. Kingsbury, ``Image processing with complex wavelets'', Phil. Trans. Royal Society London A, Sept. 1999, pp. 2543-2560.

(3) N. G. Kingsbury, ``A dual-tree complex wavelet transform with improved orthogonality and symmetry properties'', Proc. IEEE Conf. on Image Processing, Vancouver, Sept. 11-13, 2000, Paper 1429.

(4) I. Daubechies, ``Orthonormal Bases of Compactly Supported Wavelets'', Communications on Pure and, Applied Mathematics, 41, 909-96.

SEE ALSO:

, .

EXAMPLES:

   ## calculate DTWT filters
   temp <- wavDTWTFilters(bior = "nearsyma", qshift = "b")

   ## plot impulse responses of filters used in the
   ## forward DTWT
   plot(temp)

   ## plot impulse responses of filters used in the
   ## inverse DTWT
   plot(temp, forward = F)

   ## plot the squared gain response of the forward filters
   plot(temp, freq = T)

   ## summarize the filter set
   summary(temp)