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Dyadic analysis filter bank

The `dsp.DyadicAnalysisFilterBank`

System
object™ decomposes a broadband signal into a collection of subbands with smaller
bandwidths and slower sample rates. The System
object uses a series of highpass and lowpass FIR filters to provide approximate octave
band frequency decompositions of the input. Each filter output is downsampled by a factor of
two. With the appropriate analysis filters and tree structure, the dyadic analysis filter bank
is a discrete wavelet transform (DWT) or discrete wavelet packet transform (DWPT).

To obtain approximate octave band frequency decompositions of the input:

Create the

`dsp.DyadicAnalysisFilterBank`

object and set its properties.Call the object with arguments, as if it were a function.

To learn more about how System objects work, see What Are System Objects? (MATLAB).

`dydan = dsp.DyadicAnalysisFilterBank`

`dydan = dsp.DyadicAnalysisFilterBank(Name,Value)`

constructs a dyadic analysis filter bank object, `dydan`

= dsp.DyadicAnalysisFilterBank`dydan`

, that computes
the level-two discrete wavelet transform (DWT) of a column vector input. For a 2-D matrix
input, the object transforms the columns using the Daubechies third-order extremal phase
wavelet. The length of the input along the first dimension must be a multiple of 4.

`dydan = dsp.DyadicAnalysisFilterBank(`

returns a dyadic analysis filter bank object, with each property set to the specified
value.`Name,Value`

)

**For versions earlier than R2016b, use the step
function to run the System object algorithm. The arguments to
step are the object you created, followed by
the arguments shown in this section.**

**For example, y = step(obj,x) and y = obj(x) perform equivalent operations.**

`y = dydan(x)`

To use an object function, specify the
System
object as the first input argument. For
example, to release system resources of a System
object named `obj`

, use
this syntax:

release(obj)

This object implements the algorithm, inputs, and outputs described on the Dyadic Analysis Filter Bank block reference page. The object properties correspond to the block parameters, except:

The dyadic analysis filter bank object always concatenates the subbands into a
single column vector for a column vector input, or into the columns of a matrix for a
matrix input. This behavior corresponds to the block's behavior when you set the
Output parameter to ```
Single
port
``` . |