- read metadata in callback

- clamp shutter speed to frame duration minimum

ocv_rpicam.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
+
 from typing import Union, overload
-from picamera2 import Picamera2, MappedArray
+from picamera2 import Picamera2, MappedArray, Metadata
 from pprint import pprint
 import json
 import cv2
@@ -38,11 +39,10 @@ picam2 = Picamera2()
 pprint(picam2.sensor_modes)
 settings = {'NoiseReductionMode': 0, 'AeExposureMode': 0, 'ExposureTime': 10000, 'AnalogueGain': 1, 'FrameRate': picam2.sensor_modes[0]['fps']}
 caps = {"FrameRate": (1, picam2.sensor_modes[0]['fps'], None)}
-fps = 0
 
 
 def load_settings():
-    _result = None
+    _result = {}
     try:
         with open("settings.json", "r") as fp:
             _result = json.load(fp)
@@ -77,23 +77,38 @@ def set_value(item: str, value):
 def get_value(item: str):
     return picam2.camera_controls[item]
 
+fps_ist = 0
+fps_soll = 0
+
 def process(request):
-    global fps
 
     timestamp = time.strftime("%Y-%m-%d %X")
 
+    # read metadata from request
+    metadata = Metadata(request.get_metadata())
+
+    # Clamp our shutter value to minimum of FrameDuration
+    caps["ExposureTime"] = (caps["ExposureTime"][0], metadata.FrameDuration)
+
     with MappedArray(request, "main") as m:
         # Display timestamp on frame
         cv2.putText(m.array, timestamp, (0, 30), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 255, 0), 2)
 
+        if metadata is not None:
+            # Display exposure time
+            cv2.putText(m.array, f"ExposureTime  : {metadata.ExposureTime:.1f}/{shutter:.1f}", (20, m.array.shape[0] - 80), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 240, 0), 2)
+
+            # Display frame time
+            cv2.putText(m.array, f"FrameDuration : {metadata.FrameDuration:.1f}", (20, m.array.shape[0] - 50), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 240, 0), 2)
+
         # Display FPS on frame
-        cv2.putText(m.array, "FPS : " + str(int(fps)), (20, m.array.shape[0] - 20), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 240, 0), 2)
+        cv2.putText(m.array, f"Frame rate    : {fps_ist:.1f}/{fps_soll:.1f}", (20, m.array.shape[0] - 20), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 240, 0), 2)
 
 
 if __name__ == '__main__':
     for item in items:
         try:
-            caps[item] = picam2.camera_controls[item]
+            caps[item] = (picam2.camera_controls[item][0], picam2.camera_controls[item][1])
         except KeyError:
             print(f"{item}: Not implemented")
 
@@ -102,25 +117,32 @@ if __name__ == '__main__':
     camera_config = picam2.create_preview_configuration({'format': 'XRGB8888', 'size': (800, 600)})
     picam2.configure(camera_config)
 
-
+    # Load and apply our settings
     settings |= load_settings()
-    shutter = settings['ExposureTime']
-    gain = settings['AnalogueGain']
-    fps = settings['FrameRate']
     apply_settings(settings)
 
+    # Init vars
+    shutter = settings['ExposureTime']
+    gain = settings['AnalogueGain']
+    fps_soll = settings['FrameRate']
+
+    # Print status
     pprint(f"Capabilities: {caps}")
     pprint(f"Settings: {settings}")
     pprint(f"Camera config: {picam2.camera_configuration()}")
 
-    # Start
+    # Register OCV processing callback
     picam2.pre_callback = process
+
+    # Start
     picam2.start()
     
     while True:
+
         # Start timer
         timer = cv2.getTickCount()
 
+        # Capture frame
         frame = picam2.capture_array("main")
 
         # Process the frame using OpenCV operations
@@ -132,63 +154,62 @@ if __name__ == '__main__':
             break
         elif key == ord('w'):
             shutter -= 1000
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('s'):
             shutter -= 100
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('x'):
             shutter -= 1
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('e'):
             shutter += 1000
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('d'):
             shutter += 100
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('c'):
             shutter += 1
-            shutter = set_value('ExposureTime', shutter)
             print(f"Shutter: {shutter}")
         elif key == ord('h'):
             gain -= 1
-            gain = set_value('AnalogueGain', gain)
             print(f"Gain: {gain}")
         elif key == ord('j'):
             gain += 1
-            gain = set_value('AnalogueGain', gain)
             print(f"Gain: {gain}")
         elif key == ord('r'):
-            fps -= 1
+            fps_soll -= 1
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
         elif key == ord('f'):
-            fps -= 0.1
+            fps_soll -= 0.1
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
         elif key == ord('v'):
-            fps -= 0.01
+            fps_soll -= 0.01
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
         elif key == ord('t'):
-            fps += 1
+            fps_soll += 1
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
         elif key == ord('g'):
-            fps += 0.1
+            fps_soll += 0.1
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
         elif key == ord('b'):
-            fps += 0.01
+            fps_soll += 0.01
-            fps = set_value('FrameRate', fps)
+            print(f"FPS: {fps_soll}")
-            print(f"FPS: {fps}")
+
+        # Update control settings and keep vars within ranges
+        shutter = set_value('ExposureTime', shutter)
+        gain = set_value('AnalogueGain', gain)
+        fps_soll = set_value('FrameRate', fps_soll)
+
+        # Write contrrols to camera
+        with picam2.controls as controls:
+            controls.ExposureTime = shutter
+            controls.AnalogueGain = gain
+            controls.FrameRate = fps_soll
 
         # Calculate Frames per second (FPS)
-    fps = cv2.getTickFrequency() / (cv2.getTickCount() - timer)
+        fr = cv2.getTickFrequency() / (cv2.getTickCount() - timer)
+        alpha = 0.2
+        fps_ist = (1-alpha)*fps_ist + alpha*fr
 
 
     # Release the capture and close windows

settings.json

@@ -1,7 +1,7 @@
 {
 "NoiseReductionMode": 0,
 "AeExposureMode": 0,
-"ExposureTime": 75030,
+"ExposureTime": 10000,
 "AnalogueGain": 1.0,
-"FrameRate": 10.580000000000002
+"FrameRate": 60.38
 }