I want coding for feature extraction for ecg signal

Need code for feature extraction for ecg signal.

Answer 1

[Hari]

Hi Saranya,

I understand that you want to perform feature extraction on an ECG signal. Feature extraction in ECG signals typically involves identifying key points such as R-peaks, QRS complexes, and other waveform characteristics.

I assume you have an ECG signal already loaded in MATLAB and you want to extract features like R-peaks and QRS duration.

In order to perform feature extraction on an ECG signal, you can follow the below steps:

Load and Pre-process the ECG Signal:

Ensure your ECG signal is loaded and pre-processed for noise reduction, if necessary.

% Assuming 'ecgSignal' is your ECG data and 'fs' is the sampling frequency
ecgSignal = load('your_ecg_data.mat'); % Load your ECG data
fs = 1000; % Example sampling frequency in Hz

Detect R-peaks:

Use the “findpeaks” function to detect R-peaks in the ECG signal.

[~, rPeaks] = findpeaks(ecgSignal, 'MinPeakHeight', 0.5, 'MinPeakDistance', 0.6*fs);

Extract QRS Complex:

Define a window around each R-peak to extract the QRS complex.

qrsWidth = round(0.1 * fs); % QRS width in samples
qrsComplexes = arrayfun(@(r) ecgSignal(max(1, r-qrsWidth):min(length(ecgSignal), r+qrsWidth)), rPeaks, 'UniformOutput', false);

Calculate Features:

Compute features such as QRS duration and R-R intervals.

qrsDurations = cellfun(@length, qrsComplexes) / fs; % QRS duration in seconds
rrIntervals = diff(rPeaks) / fs; % R-R intervals in seconds

Output the Extracted Features:

Display or save the extracted features for further analysis.

fprintf('Average QRS Duration: %.2f seconds\n', mean(qrsDurations));
fprintf('Average R-R Interval: %.2f seconds\n', mean(rrIntervals));

Refer to the documentation of “findpeaks” function to know more about its usage:

• https://www.mathworks.com/help/signal/ref/findpeaks.html

Hope this help