Google Vision API Face Detection Python Tutorial

Quick basic python tutorial on how to detect faces in images using Google's Vision API.

Code Below:

# Imports system modules
import io
import os

def detect_faces(face_file, max_results=4):
# Initializes image from image file path
with open(face_file, 'rb') as file:
content = file.read()
image = types.Image(content=content)
# Performs face detection on the image
response = client.face_detection(image=image, max_results=max_results)
faces = response.face_annotations
likelihood_name = ('UNKNOWN', 'VERY_UNLIKELY', 'UNLIKELY', 'POSSIBLE',
'LIKELY', 'VERY_LIKELY')
print('\nDetecting faces in file: {}'.format(face_file))
for face in faces:
print('Face detection confidence: {}'.format(face.detection_confidence))
print([face.joy_likelihood])
print('joy: {}'.format(likelihood_name[face.joy_likelihood]))
print('sorrow: {}'.format(likelihood_name[face.sorrow_likelihood]))
print('anger: {}'.format(likelihood_name[face.anger_likelihood]))
print('surprise: {}'.format(likelihood_name[face.surprise_likelihood]))

def detect_faces_uri(uri, max_results=4):
# Initializes image from web url or image file path
image = vision.types.Image()
image.source.image_uri = uri
# Performs face detection on the image
response = client.face_detection(image=image)
faces = response.face_annotations

# Names of likelihood from google.cloud.vision.enums
likelihood_name = ('UNKNOWN', 'VERY_UNLIKELY', 'UNLIKELY', 'POSSIBLE',
'LIKELY', 'VERY_LIKELY')
print('\nFaces:')
for face in faces:
#print('Face detection confidence: {}'.format(face.detection_confidence))
print('anger: {}'.format(likelihood_name[face.anger_likelihood]))
print('joy: {}'.format(likelihood_name[face.joy_likelihood]))
print('surprise: {}'.format(likelihood_name[face.surprise_likelihood]))

vertices = (['({},{})'.format(vertex.x, vertex.y)
for vertex in face.bounding_poly.vertices])
print('face bounds: {}'.format(','.join(vertices)))
if input('See additional features? ') == 'yes':
print(faces)

# Main starts here --------------------------------------------------------------------------------------
credential_path = r'PATH\YOUR_API_KEY.json' #modify this line
os.environ['GOOGLE_APPLICATION_CREDENTIALS'] = credential_path

print('\nDetecting faces from url (input):')
detect_faces_uri(input('Enter image url: '))
detect_faces('rattlesnake_peak.jpg')