frigate/detect_objects.py

import cv2
import time
import queue
import yaml
import numpy as np
from flask import Flask, Response, make_response, jsonify
import paho.mqtt.client as mqtt

from frigate.video import Camera
from frigate.object_detection import PreppedQueueProcessor
from frigate.util import EventsPerSecond

with open('/config/config.yml') as f:
    CONFIG = yaml.safe_load(f)

MQTT_HOST = CONFIG['mqtt']['host']
MQTT_PORT = CONFIG.get('mqtt', {}).get('port', 1883)
MQTT_TOPIC_PREFIX = CONFIG.get('mqtt', {}).get('topic_prefix', 'frigate')
MQTT_USER = CONFIG.get('mqtt', {}).get('user')
MQTT_PASS = CONFIG.get('mqtt', {}).get('password')
MQTT_CLIENT_ID = CONFIG.get('mqtt', {}).get('client_id', 'frigate')

# Set the default FFmpeg config
FFMPEG_CONFIG = CONFIG.get('ffmpeg', {})
FFMPEG_DEFAULT_CONFIG = {
    'global_args': FFMPEG_CONFIG.get('global_args', 
        ['-hide_banner','-loglevel','panic']),
    'hwaccel_args': FFMPEG_CONFIG.get('hwaccel_args', 
        []),
    'input_args': FFMPEG_CONFIG.get('input_args',
        ['-avoid_negative_ts', 'make_zero',
         '-fflags', 'nobuffer',
         '-flags', 'low_delay',
         '-strict', 'experimental',
         '-fflags', '+genpts+discardcorrupt',
         '-vsync', 'drop',
         '-rtsp_transport', 'tcp',
         '-stimeout', '5000000',
         '-use_wallclock_as_timestamps', '1']),
    'output_args': FFMPEG_CONFIG.get('output_args',
        ['-vf', 'mpdecimate',
         '-f', 'rawvideo',
         '-pix_fmt', 'rgb24'])
}

GLOBAL_OBJECT_CONFIG = CONFIG.get('objects', {})

WEB_PORT = CONFIG.get('web_port', 5000)
DEBUG = (CONFIG.get('debug', '0') == '1')

def main():
    # connect to mqtt and setup last will
    def on_connect(client, userdata, flags, rc):
        print("On connect called")
        if rc != 0:
            if rc == 3:
                print ("MQTT Server unavailable")
            elif rc == 4:
                print ("MQTT Bad username or password")
            elif rc == 5:
                print ("MQTT Not authorized")
            else:
                print ("Unable to connect to MQTT: Connection refused. Error code: " + str(rc))
        # publish a message to signal that the service is running
        client.publish(MQTT_TOPIC_PREFIX+'/available', 'online', retain=True)
    client = mqtt.Client(client_id=MQTT_CLIENT_ID)
    client.on_connect = on_connect
    client.will_set(MQTT_TOPIC_PREFIX+'/available', payload='offline', qos=1, retain=True)
    if not MQTT_USER is None:
        client.username_pw_set(MQTT_USER, password=MQTT_PASS)
    client.connect(MQTT_HOST, MQTT_PORT, 60)
    client.loop_start()
    
    # Queue for prepped frames, max size set to number of regions * 3
    max_queue_size = sum([len(camera['regions'])*3 for name, camera in CONFIG['cameras'].items()])
    prepped_frame_queue = queue.Queue()

    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)

    fps_tracker = EventsPerSecond()
    queue_full_tracker = EventsPerSecond()

    prepped_queue_processor = PreppedQueueProcessor(
        cameras,
        prepped_frame_queue,
        fps_tracker,
        queue_full_tracker
    )
    prepped_queue_processor.start()
    fps_tracker.start()
    queue_full_tracker.start()

    for name, camera in cameras.items():
        camera.start()
        print("Capture process for {}: {}".format(name, camera.get_capture_pid()))

    # create a flask app that encodes frames a mjpeg on demand
    app = Flask(__name__)

    @app.route('/')
    def ishealthy():
        # return a healh
        return "Frigate is running. Alive and healthy!"

    @app.route('/debug/stats')
    def stats():
        stats = {
            'coral': {
                'fps': fps_tracker.eps(),
                'inference_speed': prepped_queue_processor.avg_inference_speed,
                'queue_length': prepped_frame_queue.qsize(),
                'queue_full_events_per_min': queue_full_tracker.eps(60)
            }
        }

        for name, camera in cameras.items():
            stats[name] = camera.stats()

        return jsonify(stats)

    @app.route('/<camera_name>/<label>/best.jpg')
    def best(camera_name, label):
        if camera_name in cameras:
            best_frame = cameras[camera_name].get_best(label)
            if best_frame is None:
                best_frame = np.zeros((720,1280,3), np.uint8)
            best_frame = cv2.cvtColor(best_frame, cv2.COLOR_RGB2BGR)
            ret, jpg = cv2.imencode('.jpg', best_frame)
            response = make_response(jpg.tobytes())
            response.headers['Content-Type'] = 'image/jpg'
            return response
        else:
            return f'Camera named {camera_name} not found', 404

    @app.route('/<camera_name>')
    def mjpeg_feed(camera_name):
        if camera_name in cameras:
            # return a multipart response
            return Response(imagestream(camera_name),
                            mimetype='multipart/x-mixed-replace; boundary=frame')
        else:
            return f'Camera named {camera_name} not found', 404

    def imagestream(camera_name):
        while True:
            # max out at 1 FPS
            time.sleep(1)
            frame = cameras[camera_name].get_current_frame_with_objects()
            yield (b'--frame\r\n'
                b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')

    app.run(host='0.0.0.0', port=WEB_PORT, debug=False)

    camera.join()

if __name__ == '__main__':
    main()