refactor resizing into generic priority queues

detect_objects.py

@@ -72,11 +72,12 @@ def main():
     
     # Queue for prepped frames, max size set to (number of cameras * 5)
     max_queue_size = len(CONFIG['cameras'].items())*5
-    prepped_frame_queue = queue.Queue(max_queue_size)
+    prepped_frame_queue = queue.PriorityQueue(max_queue_size)
 
     cameras = {}
     for name, config in CONFIG['cameras'].items():
-        cameras[name] = Camera(name, FFMPEG_DEFAULT_CONFIG, GLOBAL_OBJECT_CONFIG, config, prepped_frame_queue, client, MQTT_TOPIC_PREFIX)
+        cameras[name] = Camera(name, FFMPEG_DEFAULT_CONFIG, GLOBAL_OBJECT_CONFIG, config, 
+            prepped_frame_queue, client, MQTT_TOPIC_PREFIX)
 
     prepped_queue_processor = PreppedQueueProcessor(
         cameras,

frigate/object_detection.py

@@ -27,6 +27,7 @@ class PreppedQueueProcessor(threading.Thread):
             # print(self.engine.get_inference_time())
 
             # parse and pass detected objects back to the camera
+            # TODO: just send this back with all the same info you received and objects as a new property
             parsed_objects = []
             for obj in objects:
                 parsed_objects.append({
@@ -92,3 +93,67 @@ class FramePrepper(threading.Thread):
                 })
             else:
                 print("queue full. moving on")
+
+class RegionRequester(threading.Thread):
+    def __init__(self, camera):
+        self.camera = camera
+
+    def run(self):
+        frame_time = 0.0
+        while True:
+            now = datetime.datetime.now().timestamp()
+
+            with self.camera.frame_ready:
+                # if there isnt a frame ready for processing or it is old, wait for a new frame
+                if self.camera.frame_time.value == frame_time or (now - self.camera.frame_time.value) > 0.5:
+                    self.camera.frame_ready.wait()
+            
+            # make a copy of the frame_time
+            frame_time = self.camera.frame_time.value
+            
+            for index, region in enumerate(self.camera.config['regions']):
+                # queue with priority 1
+                self.camera.resize_queue.put((1, {
+                    'camera_name': self.camera.name,
+                    'frame_time': frame_time,
+                    'region_id': index,
+                    'size': region['size'],
+                    'x_offset': region['x_offset'],
+                    'y_offset': region['y_offset']
+                }))
+
+class RegionPrepper(threading.Thread):
+    def __init__(self, frame_cache, resize_request_queue, prepped_frame_queue):
+
+        threading.Thread.__init__(self)
+        self.frame_cache = frame_cache
+        self.resize_request_queue = resize_request_queue
+        self.prepped_frame_queue = prepped_frame_queue
+
+    def run(self):
+        while True:
+
+            resize_request = self.resize_request_queue.get()
+
+            frame = self.frame_cache.get(resize_request['frame_time'], None)
+            
+            if frame is None:
+                print("RegionPrepper: frame_time not in frame_cache")
+                continue
+
+            # make a copy of the region
+            cropped_frame = frame[resize_request['y_offset']:resize_request['y_offset']+resize_request['size'], resize_request['x_offset']:resize_request['x_offset']+resize_request['size']].copy()
+            
+            # Resize to 300x300 if needed
+            if cropped_frame.shape != (300, 300, 3):
+                cropped_frame = cv2.resize(cropped_frame, dsize=(300, 300), interpolation=cv2.INTER_LINEAR)
+            # Expand dimensions since the model expects images to have shape: [1, 300, 300, 3]
+            frame_expanded = np.expand_dims(cropped_frame, axis=0)
+
+            # add the frame to the queue
+            if not self.prepped_frame_queue.full():
+                resize_request['frame'] = frame_expanded.flatten().copy()
+                # add to queue with priority 1
+                self.prepped_frame_queue.put((1, resize_request))
+            else:
+                print("queue full. moving on")

frigate/video.py

@@ -2,6 +2,7 @@ import os
 import time
 import datetime
 import cv2
+import queue
 import threading
 import ctypes
 import multiprocessing as mp
@@ -9,11 +10,11 @@ import subprocess as sp
 import numpy as np
 from collections import defaultdict
 from . util import tonumpyarray, draw_box_with_label
-from . object_detection import FramePrepper
+from . object_detection import FramePrepper, RegionPrepper, RegionRequester
 from . objects import ObjectCleaner, BestFrames
 from . mqtt import MqttObjectPublisher
 
-# Stores 2 seconds worth of frames when motion is detected so they can be used for other threads
+# Stores 2 seconds worth of frames so they can be used for other threads
 class FrameTracker(threading.Thread):
     def __init__(self, shared_frame, frame_time, frame_ready, frame_lock, recent_frames):
         threading.Thread.__init__(self)
@@ -116,7 +117,7 @@ class Camera:
         self.name = name
         self.config = config
         self.detected_objects = []
-        self.recent_frames = {}
+        self.frame_cache = {}
 
         self.ffmpeg = config.get('ffmpeg', {})
         self.ffmpeg_input = get_ffmpeg_input(self.ffmpeg['input'])
@@ -145,6 +146,10 @@ class Camera:
         # Condition for notifying that objects were parsed
         self.objects_parsed = mp.Condition()
 
+        # Queue for prepped frames, max size set to (number of regions * 5)
+        max_queue_size = len(self.config['regions'])*5
+        self.resize_queue = queue.PriorityQueue(max_queue_size)
+        
         # initialize the frame cache
         self.cached_frame_with_objects = {
             'frame_bytes': [],
@@ -154,9 +159,9 @@ class Camera:
         self.ffmpeg_process = None
         self.capture_thread = None
 
-        # for each region, create a separate thread to resize the region and prep for detection
+        # for each region, merge the object config
         self.detection_prep_threads = []
-        for index, region in enumerate(self.config['regions']):
+        for region in self.config['regions']:
             region_objects = region.get('objects', {})
             # build objects config for region
             objects_with_config = set().union(global_objects_config.keys(), camera_objects_config.keys(), region_objects.keys())
@@ -166,23 +171,20 @@ class Camera:
             
             region['objects'] = merged_objects_config
 
-            self.detection_prep_threads.append(FramePrepper(
+        # start a thread to queue resize requests for regions
-                self.name,
+        self.region_requester = RegionRequester(self)
-                self.current_frame,
-                self.frame_time,
-                self.frame_ready,
-                self.frame_lock,
-                region['size'], region['x_offset'], region['y_offset'], index,
-                prepped_frame_queue
-            ))
 
-        # start a thread to store recent motion frames for processing
+        # start a thread to cache recent frames for processing
         self.frame_tracker = FrameTracker(self.current_frame, self.frame_time, 
-            self.frame_ready, self.frame_lock, self.recent_frames)
+            self.frame_ready, self.frame_lock, self.frame_cache)
         self.frame_tracker.start()
 
+        # start a thread to resize regions
+        self.region_prepper = RegionPrepper(self.frame_cache, self.resize_queue, prepped_frame_queue)
+        self.region_prepper.start()
+
         # start a thread to store the highest scoring recent frames for monitored object types
-        self.best_frames = BestFrames(self.objects_parsed, self.recent_frames, self.detected_objects)
+        self.best_frames = BestFrames(self.objects_parsed, self.frame_cache, self.detected_objects)
         self.best_frames.start()
 
         # start a thread to expire objects from the detected objects list