Google vision API example used with raspberry pi, pi camera with GPIO to trigger

config.yaml

accepted:
    - mobile phone
    - electronics
    - paper

main.py

from picamera import PiCamera
import time

import base64

from googleapiclient import discovery
from oauth2client.client import GoogleCredentials
import RPi.GPIO as GPIO
import yaml


BUTTON_PIN = 11
RED_PIN = 13
GREEN_PIN = 15


def generate_image():
    camera = PiCamera()
    file_name = "%s.jpg" % time.time()
    camera.capture(file_name)
    camera.close()
    return file_name

def generate_label(filename):
    accepted_list = yaml.load(open("config.yaml"))
    accepted = False
    credentials = GoogleCredentials.get_application_default()
    service = discovery.build('vision', 'v1', credentials=credentials)

    with open(filename, 'rb') as image:
        image_content = base64.b64encode(image.read())
        service_request = service.images().annotate(body={
            'requests': [{
                'image': {
                    'content': image_content.decode('UTF-8')
                },
                'features': [{
                    'type': 'LABEL_DETECTION',
                    'maxResults': 1
                }]
            }]
        })
        responses = service_request.execute()
        
        # label = response['responses'][0]['labelAnnotations'][0]['description']
        for response in responses['responses']:
            labels = response['labelAnnotations']
            for label in labels:
                if label['description'] in accepted_list["accepted"]:
                    accepted = True
                    print("caught it")
                print('Found label: %s for %s' % (label, filename))
    return accepted

if __name__ == "__main__":
    GPIO.setmode(GPIO.BOARD)
    GPIO.setup(BUTTON_PIN, GPIO.IN,  pull_up_down=GPIO.PUD_DOWN)
    GPIO.setup(RED_PIN, GPIO.OUT)
    GPIO.setup(GREEN_PIN, GPIO.OUT)
    # button pressed
    try:
        while True:
        
            if GPIO.input(BUTTON_PIN):
                GPIO.output(GREEN_PIN, 1)
                GPIO.output(RED_PIN, 1)
                images = generate_image()
                accepted=generate_label(images)
                if accepted:
                    GPIO.output(RED_PIN, 0)
                else:
                    GPIO.output(GREEN_PIN, 0)
                print("boom")
                time.sleep(5)
            
            GPIO.output(15, 0)
            GPIO.output(13, 0)
            time.sleep(0.1)
            print("bam")
    except Exception as e:
        print(e)
    GPIO.cleanup()