isBiorthogonal

R2026b

Determine if DWT filter bank is biorthogonal

Syntax

tf = isBiorthogonal(fb)

tf = isBiorthogonal(fb,tol)

Description

tf = isBiorthogonal(fb) returns true if the discrete wavelet transform (DWT) filter bank fb is a biorthogonal filter bank and false otherwise.

To determine if a DWT filter bank is orthogonal, use isOrthogonal.

tf = isBiorthogonal(fb,tol) uses the positive real-valued tolerance tol to determine the biorthogonality of the filter bank fb. tol is a small positive number in the interval (0, 10^-2]. If unspecified, tol defaults to 10^-5.

Examples

Biorthogonality Test of DWT Filter Bank

Check whether a filter bank is biorthogonal.

fb = dwtfilterbank('Wavelet','bior4.4');
isBiorthogonal(fb)

ans = logical
   1

Input Arguments

fb — Discrete wavelet transform filter bank

dwtfilterbank object

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

tol — Tolerance

10-5 (default) | positive scalar

Tolerance to use to determine biorthogonality of the filter bank, specified as a positive scalar in the interval (0,10-2]. The sum of both scaling filters must be within tol of √2 and the sum of both wavelet filters must be less than tol.

Extended Capabilities

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

The isBiorthogonal function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced in R2018a

R2026b: Use thread-based environments

You can use isBiorthogonal in thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.