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FilterOverlapAdd

Namespace: RTPROCESSINGLIB  ·  Library: DSP Library

#include <dsp/rt_filter.h>

class RTPROCESSINGLIB::FilterOverlapAdd

Filtering with FFT convolution and the overlap add method for continuous data streams.

This class will hold all needed information about the last block in order to overlap it with the current one.

Applies FIR filtering via FFT-based overlap-add convolution for continuous data streams.

Public Methods​

calculate(matData, type, dCenterfreq, dBandwidth, dTransition, dSFreq, iOrder, designMethod, vecPicks, bFilterEnd, bUseThreads, bKeepOverhead)​

Creates a user designed filter kernel and filters the raw input data.

Parameters:

  • matData : const Eigen::MatrixXd & The data which is to be filtered.

  • type : int The type of the filter: LPF, HPF, BPF, NOTCH (from enum FilterType).

  • dCenterfreq : double The center of the frequency.

  • dBandwidth : double The filter bandwidth. Ignored if FilterType is set to LPF,HPF. If NOTCH/BPF: bandwidth of stop-/passband.

  • dTransition : double The transition band determines the width of the filter slopes (steepness).

  • dSFreq : double The input data sampling frequency.

  • iOrder : int Represents the order of the filter, the higher the higher is the stopband attenuation. Default is 1024 taps.

  • designMethod : int The design method to use. Choose between Cosine and Tschebyscheff. Default is set to Cosine.

  • vecPicks : const Eigen::RowVectorXi & Channel indexes to filter. Default is filter all channels.

  • bFilterEnd : bool Whether to perform the overlap add in the beginning or end of the data. Default is set to true (end of data).

  • bUseThreads : bool Whether to use multiple threads. Default is set to true.

  • bKeepOverhead : bool Whether to keep the delayed part of the data after filtering. Default is set to false .

Returns:

  • Eigen::MatrixXd — The filtered data in form of a matrix.

calculate(matData, filterKernel, vecPicks, bFilterEnd, bUseThreads, bKeepOverhead)​

Calculates the filtered version of the raw input data based on a given list filters.

Parameters:

  • matData : const Eigen::MatrixXd & The data which is to be filtered.

  • filterKernel : const FilterKernel & The list of filter kernels to use.

  • vecPicks : const Eigen::RowVectorXi & Channel indexes to filter. Default is filter all channels.

  • bFilterEnd : bool Whether to perform the overlap add in the beginning or end of the data. Default is set to true (end of data).

  • bUseThreads : bool Whether to use multiple threads. Default is set to true.

  • bKeepOverhead : bool Whether to keep the delayed part of the data after filtering. Default is set to false .

Returns:

  • Eigen::MatrixXd — The filtered data in form of a matrix.

reset()​

Reset the stored overlap matrices.

Authors of this file​