Dlib library blink

See the comments

import cv2 as cv
import dlib
import imutils
import numpy as np
from imutils import face_utils as fu


def eye_aspect_ratio(eye):
    #  Calculate the Euclidean distance up and down 
    a = np.linalg.norm(eye[1] - eye[5])
    b = np.linalg.norm(eye[2] - eye[4])
    #  Calculate the left and right Euclidean distance 
    c = np.linalg.norm(eye[0] - eye[3])
    #  Calculate the aspect ratio and return 
    d = (a + b) / (2.0 * c)
    return d


COUNTER = 0
TOTAL = 0

#  Turn on the camera 
cap = cv.VideoCapture(0, cv.CAP_DSHOW)
#  Establish a face detector 
detector = dlib.get_frontal_face_detector()
#  establish 68 Key point detector 
predictor = dlib.shape_predictor('./1.dat')

#  Returns the left and right eyes of the face 68 Start and end in key points 
(lStart, lEnd) = fu.FACIAL_LANDMARKS_IDXS["left_eye"]
(rStart, rEnd) = fu.FACIAL_LANDMARKS_IDXS["right_eye"]

#  As long as the camera can be turned on correctly 
while cap.isOpened():
    #  Get every frame 
    _, frame = cap.read()
    #  Set output width 
    frame = imutils.resize(frame, width=750)
    #  Convert to gray image to speed up recognition 
    gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)
    #  Return all face frames of this frame 
    faces = detector(gray, 0)
    #  Traverse all frames 
    for face in faces:
        #  Returns the of the box 68 A coordinate 
        shape = predictor(gray, face)
        #  Into a coordinate matrix 
        shape = fu.shape_to_np(shape)
        #  Returns the coordinates of the left and right eyes 
        leftEye = shape[lStart:lEnd]
        rightEye = shape[rStart:rEnd]
        #  Calculate the aspect ratio of the left eye and the right eye 
        leftEAR = eye_aspect_ratio(leftEye)
        rightEAR = eye_aspect_ratio(rightEye)
        #  Average. 
        earAVG = (leftEAR + rightEAR) / 2.0
        #  Calculate the convex hull of the left and right eyes 
        leftEyeHull = cv.convexHull(leftEye)
        rightEyeHull = cv.convexHull(rightEye)
        #  Circle the convex hull , That is, the scope of the eyes 
        cv.drawContours(frame, [leftEyeHull], -1, (255, 255, 255), 1)
        cv.drawContours(frame, [rightEyeHull], -1, (255, 255, 255), 1)

        '''  If the aspect ratio of the eye is less than 0.3  And   continuity 3 frame   I think I close my eyes  '''
        if earAVG < 0.3:
            COUNTER += 1
        else:
            if COUNTER >= 3:
                TOTAL += 1
            COUNTER = 0

        #  Next is the processing of the output 
        #  Output blink times in the upper left corner 
        cv.putText(
            frame,
            "Blinks:{0}".format(TOTAL),
            (10, 20),
            cv.FONT_HERSHEY_COMPLEX_SMALL,
            1,
            (255, 255, 255),
            2,
            cv.LINE_AA
        )
        #  Immediate real time earAVG
        cv.putText(
            frame,
            "earAVG:{0}".format(earAVG),
            (200, 20),
            cv.FONT_HERSHEY_COMPLEX_SMALL,
            1,
            (255, 255, 255),
            2,
            cv.LINE_AA
        )
        #  The lower right corner prompts the exit message 
        cv.putText(
            frame,
            "Press 'Esc' to Quit",
            (515, 550),
            cv.FONT_HERSHEY_COMPLEX_SMALL,
            1,
            (255, 255, 255),
            2,
            cv.LINE_AA
        )
    #  Output every frame 
    cv.imshow('camera', frame)
    #  Press Esc sign out 
    if cv.waitKey(1) & 0xff == 27:
        break

#  Close all windows 
cv.destroyAllWindows()
#  Release camera 
cap.release()