Template Class SingleChannelTransferFunctionFilter

Defined in File transfer_function.hpp

Inheritance Relationships

Base Type

public filters::FilterBase< T > (Template Class FilterBase)

Class Documentation

template<typename T> class SingleChannelTransferFunctionFilter : public filters::FilterBase<T>

One-dimensional digital filter class.

This class calculates the output for \(N\) one-dimensional digital filters. The filter is described by vectors \(a\) and \(b\) and implemented using the standard difference equation:

\[\begin{eqnarray*} a[0]*y[n] = b[0]*x[n] &+& b[1]*x[n-1]+ ... + b[n_b]*x[n-n_b]\ \ &-& a[1]*y[n-1]- ... - a[n_a]*y[n-n_a] \end{eqnarray*}\]

If \(a[0]\) is not equal to 1, the coefficients are normalized by \(a[0]\).

Example xml config:

</filter>

Public Functions

SingleChannelTransferFunctionFilter(): Construct the filter.

~SingleChannelTransferFunctionFilter() override: Destructor to clean up.

virtual bool configure() override

Configure the filter with the correct number of channels and params.

Parameters:

number_of_channels – The number of inputs filtered.
config – The xml that is parsed to configure the filter.

virtual bool update(const T &data_in, T &data_out) override

Update the filter and return the data seperately.

Parameters:

data_in – vector<T> with number_of_channels elements
data_out – vector<T> with number_of_channels elements

Protected Attributes

std::unique_ptr<RealtimeCircularBuffer<T>> input_buffer_: The input sample history.

std::unique_ptr<RealtimeCircularBuffer<T>> output_buffer_: The output sample history.

T temp_

std::vector<double> a_: Transfer functon coefficients (output).

std::vector<double> b_: Transfer functon coefficients (input).