Discrete Wavelet Transform Functions and Complex Symlets

Complex-valued least asymmetric Daubechies wavelets, also known as complex symlets (see csymwavf), have the highest number of vanishing moments for a given support width. The scaling filters associated with these orthogonal wavelets have near-linear phase response and are symmetric for odd numbers of vanishing moments and least asymmetric for even numbers of vanishing moments.

Some functions that support complex symlets only support real-valued input data. For each discrete wavelet and wavelet packet transform, the table lists the supported input data, wavelet, and precision.

Function	Input Data	Wavelet	Precision
dwt	Real-valued Complex-valued	Real-valued Complex-valued	single double
idwt	Real-valued Complex-valued	Real-valued Complex-valued	single double
wavedec	Real-valued Complex-valued	Real-valued Complex-valued	single double
waverec	Real-valued Complex-valued	Real-valued Complex-valued	single double
dwt2	Real-valued	Real-valued Complex-valued	single double uint8
idwt2	Real-valued Complex-valued	Real-valued Complex-valued	double
wavedec2	Real-valued	Real-valued Complex-valued	single double uint8
waverec2	Real-valued Complex-valued	Real-valued Complex-valued	double
dwpt	Real-valued Complex-valued	Real-valued Complex-valued	single double
idwpt	Real-valued Complex-valued	Real-valued Complex-valued	single double
wpdec	Real-valued	Real-valued	double
wprec	Real-valued	Real-valued	double
wpdec2	Real-valued	Real-valued	double
wprec2	Real-valued	Real-valued	double
modwt	Real-valued Complex-valued	Real-valued	single double
imodwt	Real-valued Complex-valued	Real-valued	single double
modwpt	Real-valued Complex-valued	Real-valued	single double
imodwpt	Real-valued Complex-valued	Real-valued	single double
mdwtdec	Real-valued Complex-valued	Real-valued Complex-valued	single double
mdwtrec	Real-valued Complex-valued	Real-valued Complex-valued	single double
dldwt	Real-valued	Real-valued	single double
dlidwt	Real-valued	Real-valued	single double
dlmodwt	Real-valued Complex-valued	Real-valued	single double
swt	Real-valued	Real-valued	double
iswt	Real-valued	Real-valued	double
swt2	Real-valued	Real-valued	double
iswt2	Real-valued	Real-valued	double