manage 2 seconds worth of motion frames for processing

frigate/video.py

@@ -1,6 +1,7 @@
 import time
 import datetime
 import cv2
+import threading
 from . util import tonumpyarray
 
 # fetch the frames as fast a possible, only decoding the frames when the
@@ -38,4 +39,47 @@ def fetch_frames(shared_arr, shared_frame_time, frame_lock, frame_ready, frame_s
                 with frame_ready:
                     frame_ready.notify_all()
     
-    video.release()
+    video.release()
+
+class FrameTracker(threading.Thread):
+    def __init__(self, shared_frame, frame_time, frame_ready, frame_lock, recent_frames, motion_changed, motion_regions):
+        threading.Thread.__init__(self)
+        self.shared_frame = shared_frame
+        self.frame_time = frame_time
+        self.frame_ready = frame_ready
+        self.frame_lock = frame_lock
+        self.recent_frames = recent_frames
+        self.motion_changed = motion_changed
+        self.motion_regions = motion_regions
+
+    def run(self):
+        frame_time = 0.0
+        while True:
+            # while there is motion
+            while len([r for r in self.motion_regions if r.is_set()]) > 0:
+                now = datetime.datetime.now().timestamp()
+                # wait for a frame
+                with self.frame_ready:
+                    # if there isnt a frame ready for processing or it is old, wait for a signal
+                    if self.frame_time.value == frame_time or (now - self.frame_time.value) > 0.5:
+                        self.frame_ready.wait()
+                
+                # lock and make a copy of the frame
+                with self.frame_lock: 
+                    frame = self.shared_frame.copy().astype('uint8')
+                    frame_time = self.frame_time.value
+                
+                # add the frame to recent frames
+                self.recent_frames[frame_time] = frame
+
+                # delete any old frames
+                stored_frame_times = list(self.recent_frames.keys())
+                for k in stored_frame_times:
+                    if (now - k) > 2:
+                        del self.recent_frames[k]
+                
+                print(stored_frame_times)
+
+            # wait for the global motion flag to change
+            with self.motion_changed:
+                self.motion_changed.wait()