EpochExtractor

Namespace: UTILSLIB  ·  Library: Utilities Library

#include <utils/epoch_extractor.h>

class UTILSLIB::EpochExtractor

Segments continuous raw data into fixed-length epochs locked to events.

src/examples/ex_dsp_preprocessing/main.cpp

EpochExtractor::Params params;
params.dTmin = -0.1;
params.dTmax = 0.4;
params.dBaseMin = -0.1;
params.dBaseMax = 0.0;
const QVector<MNEEpochData> epochs = EpochExtractor::extract(raw, events, kSFreq, params, codes);
QVector<MNEEpochData> targets;
for (const MNEEpochData& epoch : epochs) {
    if (epoch.event == 1) {
        targets.append(epoch);
    }
}
const MatrixXd evoked = EpochExtractor::average(EpochExtractor::rejectMarked(targets));

---

Static Methods

extract(matData, eventSamples, dSFreq, params, eventCodes)

Extract epochs from a continuous raw data matrix.

For each event sample index the function: Cuts a window [tmin, tmax] around the event.

Applies mean baseline correction over [baseMin, baseMax] (if bApplyBaseline and the window is valid).

Marks the epoch for rejection if any channel has peak-to-peak > dThreshold (and dThreshold > 0).

Epochs whose window extends outside the data boundaries are silently skipped.

Parameters:

• matData : const Eigen::MatrixXd & Continuous raw data (n_channels × n_samples), calibrated (SI units).

• eventSamples : const QVector< int > & 0-based sample indices of events.

• dSFreq : double Sampling frequency in Hz.

• params : const Params & Extraction parameters.

• eventCodes : const QVector< int > & Optional per-event integer codes stored in MNEEpochData::event. Must be empty or the same length as eventSamples.

Returns:

• QVector< MNEEpochData > — Vector of MNEEpochData (one per valid event). Rejected epochs are included with MNEEpochData::bReject == true so callers can choose whether to exclude them.

---

average(epochs)

Compute the grand average (ERP/ERF) across all non-rejected epochs.

Parameters:

• epochs : const QVector< MNEEpochData > & Vector of extracted epochs (output of extract()).

Returns:

• Eigen::MatrixXd — Mean data matrix (n_channels × n_epoch_samples), or empty matrix if no good epochs.

---

rejectMarked(epochs)

Return only the epochs that are NOT marked for rejection.

Parameters:

• epochs : const QVector< MNEEpochData > & Input epoch vector.

Returns:

• QVector< MNEEpochData > — Subset of epochs with bReject == false.

---

Example

• Full source: src/examples/ex_dsp_preprocessing/main.cpp
• Build target: ex_dsp_preprocessing (runs under CTest)

Authors of this file

• Christoph Dinh <christoph.dinh@mne-cpp.org>