app.py

import sys
import time
import json
import pygame
import pygame.camera
from io import BytesIO
from PIL import Image as pil_image

from is_wire.core import Channel, Message, Logger
from is_msgs.image_pb2 import Image

log = Logger(name="CameraGateway")

options_file = "options.json" if len(sys.argv) < 2 else sys.argv[1]
with open(options_file, 'r') as f:
    options = json.load(f)

log.info("Options loaded from '{}'\n{}", options_file, json.dumps(options))

pygame.camera.init()
devices = pygame.camera.list_cameras()
if options['device'] not in devices:
    log.critical("Device '{}' not found.", options['device'])

cam = pygame.camera.Camera(options['device'], options['resolution'])
cam.start()


def run():
    channel = Channel(options['broker_uri'])
    log.info("Connected to {}", options['broker_uri'])

    while True:
        t0 = time.time()

        img = cam.get_image()
        data = pygame.image.tostring(img, 'RGB')
        pil_img = pil_image.frombytes('RGB', options['resolution'], data)

        if options['flip_v']:
            pil_img = pil_img.transpose(pil_image.FLIP_TOP_BOTTOM)
        if options['flip_h']:
            pil_img = pil_img.transpose(pil_image.FLIP_LEFT_RIGHT)

        bdata = BytesIO()
        pil_img.save(bdata, 'jpeg')

        pb_image = Image()
        pb_image.data = bdata.getvalue()
        msg = Message(content=pb_image)
        channel.publish(msg, topic="CameraGateway.{}.Frame".format(options['camera_id']))

        dt = time.time() - t0
        log.debug("took_ms={:.1f}", dt * 1e3)
        interval = max(0.0, 1.0 / options['fps'] - dt)
        time.sleep(interval)


if options['broker_reconnection']:
    while True:
        try:
            run()
        except:
            pass
else:
    run()

cam.stop()