Zonal flame detector

flame_detector.py

# Install raspbian lite
# run `sudo raspi-config` and enable camera
# sudo apt-get update
# sudo apt-get upgrade
# sudo apt-get install python3-picamera
# sudo apt-get install python3-rpi.gpio

from picamera.array import PiYUVArray
from picamera import PiCamera
from time import sleep
from fractions import Fraction
import numpy as np
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM)
GPIO.setup(4, GPIO.OUT)

camera = PiCamera()
camera.resolution = (320, 240)
camera.framerate = 12
camera.iso = 100
camera.shutter_speed = 50000
camera.exposure_mode = 'off'
camera.awb_gains = (Fraction(309, 256), Fraction(365, 128))

rawCapture = PiYUVArray(camera, size=(320, 240))

def flame_detected(arr):
    return round(np.mean(arr)) > 20

for frame in camera.capture_continuous(rawCapture, format="yuv", use_video_port=True):
    top_left = frame.array[:120,:160,0].flatten()
    top_right = frame.array[:120,160:,0].flatten()
    bottom_left = frame.array[120:,:160,0].flatten()
    bottom_right = frame.array[120:,160:,0].flatten()

    ascii = ""
    if flame_detected(top_left):
        ascii += "X"
        GPIO.output(4, GPIO.HIGH)
        sleep(0.05)
        GPIO.output(4, GPIO.LOW)
    else:
        ascii += "O"
    if flame_detected(top_right):
        ascii += "X"
    else:
        ascii += "O"
    ascii += "\n"
    if flame_detected(bottom_left):
        ascii += "X"
    else:
        ascii += "O"
    if flame_detected(bottom_right):
        ascii += "X"
    else:
        ascii += "O"
    ascii += "\n"
    ascii += "\n"

    print(ascii)

    rawCapture.truncate(0)

GPIO.cleanup()