glass_on_face.py

import cv2
import numpy as np

face_cascade = cv2.CascadeClassifier('/home/shahsparx/opencv-master/data/haarcascades/haarcascade_frontalface_alt.xml')
eye_cascade = cv2.CascadeClassifier('/home/shahsparx/opencv-master/data/haarcascades/haarcascade_eye.xml')

# read both the images of the face and the glasses
image = cv2.imread('sample.jpg')
glass_img = cv2.imread('glass_image.jpg')

gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

centers = []
faces = face_cascade.detectMultiScale(gray, 1.3, 5)

# iterating over the face detected
for (x, y, w, h) in faces:

    # create two Regions of Interest.
    roi_gray = gray[y:y + h, x:x + w]
    roi_color = image[y:y + h, x:x + w]
    eyes = eye_cascade.detectMultiScale(roi_gray)

    # Store the coordinates of eyes in the image to the 'center' array
    for (ex, ey, ew, eh) in eyes:
        centers.append((x + int(ex + 0.5 * ew), y + int(ey + 0.5 * eh)))

if len(centers) > 0:
    # change the given value of 2.15 according to the size of the detected face
    glasses_width = 2.16 * abs(centers[1][0] - centers[0][0])
    overlay_img = np.ones(image.shape, np.uint8) * 255
    h, w = glass_img.shape[:2]
    scaling_factor = glasses_width / w

    overlay_glasses = cv2.resize(glass_img, None, fx=scaling_factor, fy=scaling_factor, interpolation=cv2.INTER_AREA)

    x = centers[0][0] if centers[0][0] < centers[1][0] else centers[1][0]

    # The x and y variables below depend upon the size of the detected face.
    x -= 0.26 * overlay_glasses.shape[1]
    y += 0.85 * overlay_glasses.shape[0]

    # Slice the height, width of the overlay image.
    h, w = overlay_glasses.shape[:2]
    overlay_img[int(y):int(y + h), int(x):int(x + w)] = overlay_glasses

    # Create a mask and generate it's inverse.
    gray_glasses = cv2.cvtColor(overlay_img, cv2.COLOR_BGR2GRAY)
    ret, mask = cv2.threshold(gray_glasses, 110, 255, cv2.THRESH_BINARY)
    mask_inv = cv2.bitwise_not(mask)
    temp = cv2.bitwise_and(image, image, mask=mask)

    temp2 = cv2.bitwise_and(overlay_img, overlay_img, mask=mask_inv)
    final_img = cv2.add(temp, temp2)

    # imS = cv2.resize(final_img, (1366, 768))
    cv2.imshow('Lets wear Glasses', final_img)
    cv2.waitKey()
    cv2.destroyAllWindows()