spsi = waveletsupport(fb)
returns the wavelet time supports of the discrete wavelet transform (DWT) filter
bank fb. The time supports are defined as the time interval in
which all the wavelet energy occurs (> 99.99% of the energy for the default
threshold).

spsi = waveletsupport(fb,thresh)
specifies the threshold for the integrated energy. thresh is a
positive real number in the interval 0 < thresh ≤
0.05.

[spsi,sphi] = waveletsupport(fb)
returns the scaling function time supports at all levels. sphi
is a real-valued L-by-1 vector, where L is the
number of levels in the DWT filter bank fb.

[spsi,sphi,tlow,thigh] = waveletsupport(fb)
returns the instants the integrated energy in the wavelets and scaling functions
exceed thresh in tlow and the last instant
the integrated energy is less than 1 − thresh in
thigh.

fb — Discrete wavelet transform filter bank dwtfilterbank object

Discrete wavelet transform (DWT) filter bank, specified as a dwtfilterbank object.

thresh — Threshold for the integrated energy 1e-6 (default) | positive scalar

Threshold for the integrated energy, specified as a positive scalar in the
interval 0 < thresh ≤ 0.05. If unspecified,
thresh defaults to
10^{-6}.

The percent energy contained in the time support is (1 − 2 × thresh) × 100. The time support of the wavelet is defined as the first
instant the integrated energy exceeds thresh and the
last instant it is less than 1-thresh. The wavelets are
normalized to have unit energy for the computation.

spsi — Wavelet time supports real-valued column vector

Wavelet time supports, returned as a real-valued column vector of length
L, where L is the number of levels
in the DWT filter bank.

sphi — Scaling function time supports real-valued column vector

Scaling function time supports, returned as a real-valued column vector of
length L, where L is the number of
levels in the DWT filter bank.

tlow — First instants real-valued matrix

First instants the integrated energy in the wavelet and scaling functions
exceed thresh, returned as real-valued
L-by-2 matrix, where L is the
number of levels in the filter bank. The first column of
tlow contains the times for the wavelets. The
second column of tlow contains the times for the
scaling functions.

The difference between the first column of thigh and
the first column of tlow plus one sampling period
equals pspi. The difference between the second column
of thigh and the second column of
tlow plus one sampling period equals
sphi.

thigh — Last instants real-valued matrix

Last instants the integrated energy in the wavelet and scaling functions
is less than 1−thresh, returned as real-valued
L-by-2 matrix, where L is the
number of levels in the filter bank. The first column of
thigh contains the times for the wavelets. The
second column of thigh contains the times for the
scaling functions.

The difference between the first column of thigh and
the first column of tlow plus one sampling period
equals pspi. The difference between the second column
of thigh and the second column of
tlow plus one sampling period equals
sphi.

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