Raspberry Pi + Picamera = Photobox

photobox.py

#!/usr/bin/env python3

import bottle
import datetime
import picamera
import RPi.GPIO as GPIO
import sys
import signal
import threading
import time

previewRes = (640,480)
captureRes = (2592,1944)
buttonPin  = 12
flashPin   = 22
countdown  = 5
abort      = False
cv         = threading.Condition()

# Initialize camera
camera = picamera.PiCamera(framerate=30)
camera.annotate_text_size = 160

# Initialize GPIOs
GPIO.setmode(GPIO.BOARD)
GPIO.setup(buttonPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(flashPin, GPIO.OUT)

def runCamera():
    camera.start_preview()

    while not abort:
        print("starting preview")
        camera.resolution = previewRes

        with cv:
            cv.wait()

        if abort:
          break

        # Take a picture without annotation
        threading.Thread(name='flashing', target=flash).start()

        camera.annotate_text = ""
        camera.resolution = captureRes
        filename = 'box-{}.jpg'.format(datetime.datetime.utcnow().isoformat())
        print("saving picture as {}".format(filename))
        camera.capture(filename)

def runButton():
  while not abort:
    input_state = GPIO.input(buttonPin)
    if input_state == False:
      print('button Pressed')

      takePicture(count=True)
      time.sleep(0.2)

def flash():
  print("flashing")
  GPIO.output(flashPin, GPIO.HIGH)
  time.sleep(0.5)
  GPIO.output(flashPin, GPIO.LOW)

def takePicture(count=False):
  if count:
    for i in range(countdown):
      if abort:
        return
      text = str(countdown-i)
      camera.annotate_text = text
      print('countdown: {}'.format(text))
      time.sleep(1)

  with cv:
    cv.notify()

def shutdown():
  print("shutting down")
  global abort
  abort = True
  takePicture()

def stdinLoop():
  while not abort:
    ch = sys.stdin.read(1)

    if ch == 'c':
        # auslösen mit Countdown
        takePicture(count=True)
    if ch == 'p':
        # sofort auslösen
        takePicture()
    elif ch == 'f':
        # Flash
        flash()

def signal_handler(signal, frame):
    print('signal received:', signal)
    shutdown()


if __name__ == "__main__":
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGINT, signal_handler)

    # Create threads
    threads = [
      threading.Thread(target=runCamera),
      threading.Thread(target=runButton),
    ]

    # Start threads
    for t in threads:
      t.start()

    # CLI
    threading.Thread(target=stdinLoop, daemon=True).start()

    # Wait for signal
    signal.pause()

    print("waiting for threads")
    for t in threads:
        t.join()

    GPIO.cleanup()
    print("exiting main thread")