eog with low pass filter of 10Hz

Author: PayalLakra

applications/eog.py

@@ -0,0 +1,86 @@
+import numpy as np
+from scipy.signal import butter, filtfilt
+from PyQt5.QtWidgets import QApplication, QVBoxLayout, QMainWindow, QWidget
+from pyqtgraph import PlotWidget
+import pyqtgraph as pg
+import pylsl
+import sys
+
+class EOGMonitor(QMainWindow):
+    def __init__(self): 
+        super().__init__()
+
+        self.setWindowTitle("Real-Time EOG Monitor - Eye Blink Detection")
+        self.setGeometry(100, 100, 800, 400)
+
+        # Create layout
+        layout = QVBoxLayout()
+
+        # Create plot widget for EOG
+        self.eog_plot = PlotWidget(self)
+        self.eog_plot.setBackground('w')
+        self.eog_plot.showGrid(x=True, y=True)
+        self.eog_plot.setTitle("Filtered EOG Signal (Low Pass: 10 Hz)")
+
+        # Add plot to layout
+        layout.addWidget(self.eog_plot)
+
+        # Central widget
+        central_widget = QWidget()
+        central_widget.setLayout(layout)
+        self.setCentralWidget(central_widget)
+
+        # Set up LSL stream inlet
+        streams = pylsl.resolve_stream('name', 'BioAmpDataStream')
+        if not streams:
+            print("No LSL stream found!")
+            sys.exit(0)
+        self.inlet = pylsl.StreamInlet(streams[0])
+
+        # Sampling rate
+        self.sampling_rate = int(self.inlet.info().nominal_srate())
+        print(f"Sampling rate: {self.sampling_rate} Hz")
+        
+        # Data and buffer
+        self.buffer_size = self.sampling_rate * 5  # 5 seconds buffer for recent data
+        self.eog_data = np.zeros(self.buffer_size)
+        self.time_data = np.linspace(0, 5, self.buffer_size)
+        self.current_index = 0
+
+        # Low-pass filter for EOG (10 Hz)
+        self.b, self.a = butter(4, 10.0 / (0.5 * self.sampling_rate), btype='low')
+
+        # Set fixed axis ranges
+        self.eog_plot.setXRange(0, 5, padding=0)
+        if self.sampling_rate == 250:
+            self.eog_plot.setYRange(-((2**10)/2), ((2**10)/2), padding=0)
+        elif self.sampling_rate == 500:
+            self.eog_plot.setYRange(-((2**14)/2), ((2**14)/2), padding=0)
+
+        # Plot curve for EOG data
+        self.eog_curve = self.eog_plot.plot(self.time_data, self.eog_data, pen=pg.mkPen('b', width=1))
+
+        # Timer for plot update
+        self.timer = pg.QtCore.QTimer()
+        self.timer.timeout.connect(self.update_plot)
+        self.timer.start(15)
+
+    def update_plot(self):
+        samples, _ = self.inlet.pull_chunk(timeout=0.0, max_samples=30)
+        if samples:
+            for sample in samples:
+                # Overwrite the oldest data point in the buffer
+                self.eog_data[self.current_index] = sample[0]
+                self.current_index = (self.current_index + 1) % self.buffer_size
+
+            # Apply only the low-pass filter to the EOG data
+            filtered_eog = filtfilt(self.b, self.a, self.eog_data)
+
+            # Update curve with the low-pass filtered EOG signal
+            self.eog_curve.setData(self.time_data, filtered_eog)
+
+if __name__ == "__main__":
+    app = QApplication(sys.argv)
+    window = EOGMonitor()
+    window.show()
+    sys.exit(app.exec_())