NaturewatchCameraServer with Button SHIM support

NaturewatchCameraServer.py

#!/usr/bin/env python
import json
import cv2
import os
import imutils
import buttonshim
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
from SocketServer import ThreadingMixIn
from ChangeDetector import ChangeDetector
import time

from threading import Thread

os.chdir("/home/pi/NaturewatchCameraServer")
config = json.load(open("config.json"))
os.chdir("/var/www/html/photos")

# NatureCam implementation
changeDetectorInstance = ChangeDetector(config)



# Handle HTTP requests.
class CamHandler(BaseHTTPRequestHandler):
    def do_GET(self):
        print(self.path)
        if self.path.endswith('.mjpg'):
            self.send_response(200)
            self.send_header('Content-type', 'multipart/x-mixed-replace; boundary=--jpgboundary')
            self.end_headers()
            print("Serving mjpg...")
            while True:
                img = changeDetectorInstance.get_current_image()
                r, buf = cv2.imencode(".jpg", img)
                self.wfile.write("--jpgboundary\r\n")
                self.send_header('Content-type', 'image/jpeg')
                self.send_header('Content-length', str(len(buf)))
                self.end_headers()
                self.wfile.write(bytearray(buf))
                self.wfile.write('\r\n')

        if self.path.endswith('less'):
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            changeDetectorInstance.minWidth = config["less_sensitivity"]
            changeDetectorInstance.minHeight = config["less_sensitivity"]
            return

        if self.path.endswith('more'):
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            changeDetectorInstance.minWidth = config["more_sensitivity"]
            changeDetectorInstance.minHeight = config["more_sensitivity"]
            return

        if self.path.endswith('default'):
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            changeDetectorInstance.minWidth = config["min_width"]
            changeDetectorInstance.minHeight = config["min_width"]
            return

        if self.path.endswith('start'):
            buttonshim.set_pixel(128, 0, 0)
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            changeDetectorInstance.arm()
            return

        if self.path.endswith('stop'):
            buttonshim.set_pixel(0, 128, 0)
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            changeDetectorInstance.disarm()
            return

        if self.path.endswith('delete-final'):
            self.send_response(200)
            self.send_header('Content-type', 'text/html')
            self.end_headers()
            self.wfile.write('success')
            os.system('rm /var/www/html/photos/*')
            return

        if self.path.endswith('get-status'):
            self.send_response(200)
            self.send_header('Content-type', 'application/json')
            self.end_headers()
            sensitivity = "unknown"
            if changeDetectorInstance.minWidth == config["less_sensitivity"]:
                sensitivity = "less"
            elif changeDetectorInstance.minWidth == config["min_width"]:
                sensitivity = "default"
            elif changeDetectorInstance.minWidth == config["more_sensitivity"]:
                sensitivity = "more"
            send_data = {
                "mode": changeDetectorInstance.mode,
                "sensitivity": sensitivity
            }
            json_data = json.dumps(send_data)
            self.wfile.write(json_data)
            return


# Threaded server
class ThreadedHTTPServer(ThreadingMixIn, HTTPServer):
    """Handle requests in separate threads"""


def main():
    try:
        changeDetectorInstance.start()
        server = ThreadedHTTPServer(('', 9090), CamHandler)

        @buttonshim.on_press(buttonshim.BUTTON_B)
        def btn_arm(button, pressed):
            changeDetectorInstance.arm()
            buttonshim.set_pixel(128, 0, 0)

        @buttonshim.on_press(buttonshim.BUTTON_C)
        def btn_disarm(button, pressed):
            changeDetectorInstance.disarm()
            buttonshim.set_pixel(0, 128, 0)

        @buttonshim.on_press(buttonshim.BUTTON_A)
        def btn_take_photo(button, pressed):
            hrs = changeDetectorInstance.hiResStream.next()
            hi_res_image = hrs.array
            changeDetectorInstance.hiResCapture.truncate(0)
            changeDetectorInstance.hiResCapture.seek(0)
            t_save = Thread(target=changeDetectorInstance.take_photo, args=[hi_res_image])
            t_save.start()
            changeDetectorInstance.numOfPhotos += 1
            changeDetectorInstance.lastPhotoTime = time.time()
            print("Photo snapped")

        print("server started")
        server.serve_forever()
    except (KeyboardInterrupt, SystemExit):
        changeDetectorInstance.cancel()
        server.socket.close()


if __name__ == '__main__':
    main()

Currently this code does:

• Button A - Snap a photo on demand
• Button B - Arm the camera, LED should light up red
• Button C - Disarm the camera, LED should light up green

The LED will also change when arming/disarming via the web UI.

Suggestions for D and E welcome!

You can buy a Button SHIM from here: https://shop.pimoroni.com/products/button-shim
And you'll also need a header:

• Solderless with hammer header kit: https://shop.pimoroni.com/products/gpio-hammer-header?variant=35643318026
• (or) Solder directly down onto the Pi: https://shop.pimoroni.com/products/male-40-pin-2x20-hat-header?variant=10476117383

To get this code installed you need an HDMI adaptor, and a USB adaptor plus a keyboard. Fire up your camera with HDMI and keyboard connected to run the commands below.

Save the Button SHIM python-buttonshim_0.0.2_all.deb package from https://github.com/pimoroni/button-shim/releases/tag/v0.0.2 onto the /boot partition of your camera along with this code, and install with:

• sudo dpkg -i /boot/python-buttonshim_0.0.2_all.deb.
• mv ~/NaturewatchCameraServer/NaturewatchCameraServer.py ~/NaturewatchCameraServer/NaturewatchCameraServer-backup.py
• cp /boot/NaturewatchCameraServer.py ~/NaturewatchCameraServer/NaturewatchCameraServer.py

You will also need to edit /boot/config.txt and uncomment the line #dtparam=i2c_arm=on so that it reads dtparam=i2c_arm=on