add perf_counter widget for accuracy check

README.md

@@ -88,3 +88,13 @@ Once you've launched MultiWebCam, choose a new project directory through the Fil
 MWC will attempt to connect to the cameras currently and will create a `recording_config.toml` file in the project directory. 
 
 From the `Mode` menu you can select single camera to change camera settings (such as resolution and exposure). On the MultCamera mode you can set the target fps to achieve a desired dropped frame rate and record batches of videos.
+
+## Checking Against System Clock
+
+To provide a check of the accuracy of the time stamps, you can launch a widget that displays the `perf_counter` from the system by running from the command line:
+
+```
+mwc clock
+```
+
+Cross checking the frames with the recorded time stamp value can provide a sense of the temporal accuracy of the recording. 

multiwebcam/__main__.py

@@ -11,10 +11,10 @@
 
 def CLI_parser():
     if len(sys.argv) == 1:
-        launch_main()
+        launch_main(show_clock=False)
 
     if len(sys.argv) == 2:
-        launch_widget = sys.argv[1]
+        modifiers = sys.argv[1]
 
-        if launch_widget in ["record", "rec", "-r"]:
-            pass
+        if modifiers in ["clock", "-c"]:
+            launch_main(show_clock=True)

multiwebcam/gui/main_widget.py

@@ -1,6 +1,7 @@
 import multiwebcam.logger
 from pathlib import Path
 
+
 import subprocess
 import os
 from threading import Thread
@@ -23,6 +24,7 @@
 from multiwebcam.gui.single_camera_widget import (
     SingleCameraWidget,
 )
+from multiwebcam.gui.perf_counter_widget import PerfCounterWidget
 from multiwebcam.gui.multicamera_widget import MultiCameraWidget
 
 logger = multiwebcam.logger.get(__name__)
@@ -250,12 +252,17 @@ def update_app_settings(self):
             rtoml.dump(self.app_settings, f)
 
 
-def launch_main():
+def launch_main(show_clock=False):
     # import qdarktheme
 
     app = QApplication(sys.argv)
     # qdarktheme.setup_theme("auto")
     window = MainWindow()
+
+    if show_clock:
+        widget = PerfCounterWidget()
+        widget.show()
+
     window.show()
     app.exec()
 

multiwebcam/gui/perf_counter_widget.py

@@ -0,0 +1,47 @@
+import sys
+from PySide6.QtWidgets import QApplication, QWidget, QVBoxLayout, QLabel
+from PySide6.QtCore import QTimer
+from PySide6.QtGui import QFont
+import time
+
+class PerfCounterWidget(QWidget):
+    def __init__(self):
+        super().__init__()
+
+        # Set up the layout
+        self.layout = QVBoxLayout()
+        self.perfLabel = QLabel(self)
+
+        font = QFont()
+        font.setPointSize(100)
+        self.perfLabel.setFont(font)
+
+        self.layout.addWidget(self.perfLabel)
+        self.setLayout(self.layout)
+
+
+
+        # Timer to update the label every 100 milliseconds for smoother updates
+        self.timer = QTimer(self)
+        self.timer.timeout.connect(self.updateLabel)
+        self.timer.start(10)  # Update interval in milliseconds
+
+
+    def updateLabel(self):
+        # Calculate elapsed time since the start of the application
+        elapsedTime = time.perf_counter()
+        # Update the label with the current perf_counter value
+        self.perfLabel.setText(f"{elapsedTime:.4f}")
+
+
+
+def main():
+    app = QApplication(sys.argv)
+    widget = PerfCounterWidget()
+    widget.show()
+    sys.exit(app.exec_())
+
+if __name__ == "__main__":
+
+    main()
+