recognize.py

# face verification with the VGGFace2 model
from matplotlib import pyplot
from PIL import Image
from numpy import asarray
from scipy.spatial.distance import cosine
from mtcnn.mtcnn import MTCNN
from keras_vggface.vggface import VGGFace
from keras_vggface.utils import preprocess_input
import pandas as pd

col_names = ['Name','Faculty Number', 'Status']
#data-frame
df = pd.read_csv("data.csv", usecols=col_names, index_col=col_names[0])
message = ""

# extract a single face from a given photograph
def extract_face(filename, required_size=(224, 224)):
	# load image from file
	pixels = pyplot.imread(filename)
	# create the detector, using default weights
	detector = MTCNN()
	# detect faces in the image
	results = detector.detect_faces(pixels)
	# extract the bounding box from the first face
	x1, y1, width, height = results[0]['box']
	x2, y2 = x1 + width, y1 + height
	# extract the face
	face = pixels[y1:y2, x1:x2]
	# resize pixels to the model size
	image = Image.fromarray(face)
	image = image.resize(required_size)
	face_array = asarray(image)
	return face_array

# extract faces and calculate face embeddings for a list of photo files
def get_embeddings(filenames):
	# extract faces
	faces = [extract_face(f) for f in filenames]
	# convert into an array of samples
	samples = asarray(faces, 'float32')
	# prepare the face for the model, e.g. center pixels
	samples = preprocess_input(samples, version=2)
	# create a vggface model
	model = VGGFace(model='resnet50', include_top=False, input_shape=(224, 224, 3), pooling='avg')
	# perform prediction
	yhat = model.predict(samples)
	return yhat

# determine if a candidate face is a match for a known face
def is_match(known_embedding, candidate_embedding, name, thresh=0.5):
	# calculate distance between embeddings
	score = cosine(known_embedding, candidate_embedding)
	if score <= thresh:
		print('>face is a Match (%.3f <= %.3f)' % (score, thresh))
		message = 'Thank you! '+ name + ". Marked Present!"
		print(message)
	else:
		print('>face is NOT a Match (%.3f > %.3f)' % (score, thresh))
		message = 'Oops! Seems its NOT YOU :('
		print(message)

def verification():

	with open('Names.txt', 'r') as f:
		student_name = f.read()
	# define filenames
	filenames = ['image_db/'+ student_name +'.jpeg', 'captured/'+ student_name +'.jpeg']
	# get embeddings file filenames
	embeddings = get_embeddings(filenames)

	# define sharon stone
	sharon_id = embeddings[0]
	# verify known photos of sharon
	#print('Positive Tests')
	is_match(embeddings[0], embeddings[1], student_name)