switch to a queue for detected objects and expire objects after 1 second

detect_objects.py

@@ -81,51 +81,63 @@ def detect_objects(cropped_frame, sess, detection_graph, region_size, region_x_o
         score = scores[0, index]
         if score > 0.5:
             box = boxes[0, index].tolist()
-            box[0] = (box[0] * region_size) + region_y_offset
+            objects.append({
-            box[1] = (box[1] * region_size) + region_x_offset
+                        'name': str(category_index.get(value).get('name')),
-            box[2] = (box[2] * region_size) + region_y_offset
+                        'score': float(score),
-            box[3] = (box[3] * region_size) + region_x_offset
+                        'ymin': int((box[0] * region_size) + region_y_offset),
-            objects += [value, scores[0, index]] + box
+                        'xmin': int((box[1] * region_size) + region_x_offset),
-        # only get the first 10 objects
+                        'ymax': int((box[2] * region_size) + region_y_offset),
-        if len(objects) == 60:
+                        'xmax': int((box[3] * region_size) + region_x_offset)
-            break
+                    })
 
     return objects
 
 class ObjectParser(threading.Thread):
-    def __init__(self, objects_changed, objects_parsed, object_arrays):
+    def __init__(self, object_queue, objects_parsed):
         threading.Thread.__init__(self)
-        self._objects_changed = objects_changed
+        self._object_queue = object_queue
         self._objects_parsed = objects_parsed
-        self._object_arrays = object_arrays
 
     def run(self):
         global DETECTED_OBJECTS
         while True:
-            detected_objects = []
+            obj = self._object_queue.get()
-            # wait until object detection has run
+            print(obj)
-            # TODO: what if something else changed while I was processing???
+            DETECTED_OBJECTS.append(obj)
-            with self._objects_changed:
-                self._objects_changed.wait()
 
-            for object_array in self._object_arrays:
-                object_index = 0
-                while(object_index < 60 and object_array[object_index] > 0):
-                    object_class = object_array[object_index]
-                    detected_objects.append({
-                        'name': str(category_index.get(object_class).get('name')),
-                        'score': object_array[object_index+1],
-                        'ymin': int(object_array[object_index+2]),
-                        'xmin': int(object_array[object_index+3]),
-                        'ymax': int(object_array[object_index+4]),
-                        'xmax': int(object_array[object_index+5])
-                    })
-                    object_index += 6
-            DETECTED_OBJECTS = detected_objects
             # notify that objects were parsed
             with self._objects_parsed:
                 self._objects_parsed.notify_all()
 
+class ObjectCleaner(threading.Thread):
+    def __init__(self, objects_parsed):
+        threading.Thread.__init__(self)
+        self._objects_parsed = objects_parsed
+
+    def run(self):
+        global DETECTED_OBJECTS
+        while True:
+
+            # expire the objects that are more than 1 second old
+            now = datetime.datetime.now().timestamp()
+            # look for the first object found within the last second
+            # (newest objects are appended to the end)
+            detected_objects = DETECTED_OBJECTS.copy()
+            num_to_delete = 0
+            for obj in detected_objects:
+                if now-obj['frame_time']<1:
+                    break
+                num_to_delete += 1
+            if num_to_delete > 0:
+                del DETECTED_OBJECTS[:num_to_delete]
+
+                # notify that parsed objects were changed
+                with self._objects_parsed:
+                    self._objects_parsed.notify_all()
+            
+            # wait a bit before checking for more expired frames
+            time.sleep(0.2)
+
 class MqttMotionPublisher(threading.Thread):
     def __init__(self, client, topic_prefix, motion_changed, motion_flags):
         threading.Thread.__init__(self)
@@ -165,19 +177,16 @@ class MqttObjectPublisher(threading.Thread):
 
             # initialize the payload
             payload = {}
-            for obj in self.object_classes:
-                payload[obj] = []
 
             # wait until objects have been parsed
             with self.objects_parsed:
                 self.objects_parsed.wait()
 
-            # loop over detected objects and populate
+            # add all the person scores in detected objects and 
-            # the payload
+            # average over past 1 seconds (5fps)
             detected_objects = DETECTED_OBJECTS.copy()
-            for obj in detected_objects:
+            avg_person_score = sum([obj['score'] for obj in detected_objects if obj['name'] == 'person'])/5
-                if obj['name'] in self.object_classes:
+            payload['person'] = int(avg_person_score*100)
-                    payload[obj['name']].append(obj)
 
             # send message for objects if different
             new_payload = json.dumps(payload, sort_keys=True)
@@ -229,10 +238,10 @@ def main():
     frame_ready = mp.Condition()
     # Condition for notifying that motion status changed globally
     motion_changed = mp.Condition()
-    # Condition for notifying that object detection ran
-    objects_changed = mp.Condition()
     # Condition for notifying that objects were parsed
     objects_parsed = mp.Condition()
+    # Queue for detected objects
+    object_queue = mp.Queue()
     # shape current frame so it can be treated as an image
     frame_arr = tonumpyarray(shared_arr).reshape(frame_shape)
 
@@ -244,11 +253,10 @@ def main():
     motion_processes = []
     for region in regions:
         detection_process = mp.Process(target=process_frames, args=(shared_arr, 
-            region['output_array'],
+            object_queue,
             shared_frame_time,
             frame_lock, frame_ready,
             region['motion_detected'],
-            objects_changed,
             frame_shape, 
             region['size'], region['x_offset'], region['y_offset'],
             False))
@@ -267,8 +275,10 @@ def main():
         motion_process.daemon = True
         motion_processes.append(motion_process)
 
-    object_parser = ObjectParser(objects_changed, objects_parsed, [region['output_array'] for region in regions])
+    object_parser = ObjectParser(object_queue, objects_parsed)
     object_parser.start()
+    object_cleaner = ObjectCleaner(objects_parsed)
+    object_cleaner.start()
 
     client = mqtt.Client()
     client.will_set(MQTT_TOPIC_PREFIX+'/available', payload='offline', qos=1, retain=True)
@@ -347,6 +357,7 @@ def main():
     for motion_process in motion_processes:
         motion_process.join()
     object_parser.join()
+    object_cleaner.join()
     mqtt_publisher.join()
 
 # convert shared memory array into numpy array
@@ -391,8 +402,8 @@ def fetch_frames(shared_arr, shared_frame_time, frame_lock, frame_ready, frame_s
     video.release()
 
 # do the actual object detection
-def process_frames(shared_arr, shared_output_arr, shared_frame_time, frame_lock, frame_ready, 
+def process_frames(shared_arr, object_queue, shared_frame_time, frame_lock, frame_ready, 
-                   motion_detected, objects_changed, frame_shape, region_size, region_x_offset, region_y_offset,
+                   motion_detected, frame_shape, region_size, region_x_offset, region_y_offset,
                    debug):
     debug = True
     # shape shared input array into frame for processing
@@ -429,10 +440,10 @@ def process_frames(shared_arr, shared_output_arr, shared_frame_time, frame_lock,
         cropped_frame_rgb = cv2.cvtColor(cropped_frame, cv2.COLOR_BGR2RGB)
         # do the object detection
         objects = detect_objects(cropped_frame_rgb, sess, detection_graph, region_size, region_x_offset, region_y_offset, debug)
-        # copy the detected objects to the output array, filling the array when needed
+        for obj in objects:
-        shared_output_arr[:] = objects + [0.0] * (60-len(objects))
+            obj['frame_time'] = frame_time
-        with objects_changed:
+            object_queue.put(obj)
-            objects_changed.notify_all()
+
 
 # do the actual motion detection
 def detect_motion(shared_arr, shared_frame_time, frame_lock, frame_ready, motion_detected, motion_changed,