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Discrete wavelet transform filter bank

Use `dwtfilterbank`

to create a discrete wavelet transform
(DWT) filter bank. With the filter bank, you can visualize wavelets and scaling
functions in time and frequency. You can measure the 3-dB bandwidths of the wavelet and
scaling functions. You can measure the energy concentration of the wavelet and scaling
functions in the theoretic DWT passbands. You can determine if the filter bank is
orthogonal or biorthogonal. You can also determine the frame bounds of the filter bank.
You can create a filter bank using your own custom filters.

`fb = dwtfilterbank`

`fb = dwtfilterbank(Name,Value)`

create a discrete
wavelet transform (DWT) filter bank. The default filter bank is designed for a
signal with 1024 samples. The default filter bank uses the analysis
(decomposition) sym4 wavelet and scaling filter with seven resolution
levels.`fb`

= dwtfilterbank

creates a DWT filter bank `fb`

= dwtfilterbank(`Name,Value`

)`fb`

with properties specified by
one or more `Name,Value`

pair arguments. Properties can be
specified in any order as `Name1,Value1,...,NameN,ValueN`

.
Enclose each property name in quotes.

You cannot change a property value of an existing filter bank. For
example, if you have a filter bank `fb`

for the
`sym4`

wavelet, you must create a second filter
bank `fb2`

for the `coif5`

wavelet .
You cannot assign a different `Wavelet`

to
`fb`

.

`dwtpassbands` | DWT filter bank passbands |

`filters` | DWT filter bank filters |

`framebounds` | DWT filter bank frame bounds |

`freqz` | DWT filter bank frequency responses |

`isBiorthogonal` | Determine if DWT filter bank is biorthogonal |

`isOrthogonal` | Determine if DWT filter bank is orthogonal |

`powerbw` | DWT filter bank power bandwidth |

`qfactor` | DWT filter bank quality factor |

`scalingfunctions` | DWT filter bank time-domain scaling functions |

`wavelets` | DWT filter bank time-domain wavelets |

`waveletsupport` | DWT filter bank time supports |

[1] Daubechies, I. *Ten
Lectures on Wavelets*. CBMS-NSF Regional Conference Series in Applied
Mathematics. Philadelphia, PA: Society for Industrial and Applied Mathematics,
1992.