working camera movement

halloween/camera.py

@@ -1,5 +1,6 @@
 """Ein Kameraproduzent für mehrere Livebild-Betrachter."""
 
+from collections import deque
 from io import BytesIO
 import threading
 import time
@@ -9,6 +10,7 @@ from PIL import Image, ImageDraw
 
 
 class CameraStream:
+    TARGET_FPS = 15
     def __init__(self, demo: bool = False):
         self.demo = demo
         self._condition = threading.Condition()
@@ -16,6 +18,7 @@ class CameraStream:
         self._stop = threading.Event()
         self._frame = None
         self._number = 0
+        self._frame_times = deque(maxlen=45)
         self._time = None
         self.error = None
 
@@ -43,6 +46,7 @@ class CameraStream:
             self._frame = frame
             self._number += 1
             self._time = time.monotonic()
+            self._frame_times.append(self._time)
             self._condition.notify_all()
 
     def _run(self):
@@ -75,15 +79,17 @@ class CameraStream:
         try:
             # BGR888 liefert laut Picamera2-Dokumentation RGB-Arrays für PIL.
             config = camera.create_video_configuration(
-                main={"size": (640, 480), "format": "BGR888"}
+                main={"size": (640, 480), "format": "BGR888"},
+                controls={"FrameDurationLimits": (66667, 66667)}, queue=False
             )
             camera.configure(config)
             camera.start()
             started = True
             while not self._stop.is_set():
+                began = time.monotonic()
                 pixels = camera.capture_array("main")
                 self._publish(self._jpeg(Image.fromarray(pixels, "RGB")))
-                self._stop.wait(0.2)
+                self._stop.wait(max(0., 1/self.TARGET_FPS-(time.monotonic()-began)))
         finally:
             try:
                 if started:
@@ -114,7 +120,12 @@ class CameraStream:
     def status(self):
         with self._condition:
             age = None if self._time is None else round(time.monotonic() - self._time, 1)
+            times = self._frame_times
+            fps = ((len(times)-1)/(times[-1]-times[0])
+                   if len(times)>1 and times[-1]>times[0] and age is not None and age<1 else 0.)
             return {
+                "fps": round(fps, 1),
+                "target_fps": 5 if self.demo else self.TARGET_FPS,
                 "source": "Demo" if self.demo else "Pi-Kamera",
                 "ready": self._frame is not None and age is not None and age < 3,
                 "frame_age_seconds": age,