import cv2
import mediapipe as mp
import numpy as np


mp_face_mesh = mp.solutions.face_mesh


def get_forehead_mask(img):
with mp_face_mesh.FaceMesh(static_image_mode=True) as face_mesh:
results = face_mesh.process(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
mask = np.zeros(img.shape[:2], dtype=np.uint8)


if results.multi_face_landmarks:
for face_landmarks in results.multi_face_landmarks:
points = []
for i in [10, 338, 297, 332, 284, 251, 389, 356, 454]:
lm = face_landmarks.landmark[i]
x = int(lm.x * img.shape[1])
y = int(lm.y * img.shape[0])
points.append((x, y))
points = np.array([points], dtype=np.int32)
cv2.fillPoly(mask, points, 255)


return mask