创建训练数据时面部识别错误

Question

我指的是这段视频，以创建训练模型。

[使用OpenCV用脸解锁应用程序] ：https://www.youtube.com/watch?v=pXYJUrpQgzg

[Github链接] https://github.com/krishnaik06/Unlock-Application/blob/master/Face%20Recognition%20%E2%80%93%20Unlock%20Your%20Computer%20With%20Your%20Face!%20-%20Copy.ipynb
但执行时出现错误。请帮忙

以下是代码：

a_times_3 = a + (a << 1)
a_times_15 = a_times_3 + (a_times_3 << 2)
a_times_13 = a_times_15 - (a << 1)

预期产量->收集样品完成

我的输出->

import cv2

import numpy as np

#Load HAAR face classifier

face_classifier = cv2.CascadeClassifier('Haarcascades/haarcascade_frontalface_default.xml')

#Load functions
def face_extractor(img):
   #Function detects faces and returns the cropped face
   #If no face detected, it returns the input image

    gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
    faces = face_classifier.detectMultiScale(gray, 1.3, 5)

    if faces is ():
        return None

   #Crop all faces found
    for (x,y,w,h) in faces:
        cropped_face = img[y:y+h, x:x+w]

    return cropped_face

 #Initialize Webcam
cap = cv2.VideoCapture(0)
count = 0

#Collect 100 samples of your face from webcam input
while True:

    ret, frame = cap.read()
    if face_extractor(frame) is not None:
        count += 1
        face = cv2.resize(face_extractor(frame), (200, 200))
        face = cv2.cvtColor(face, cv2.COLOR_BGR2GRAY)

    #save file in specified directory with unique name
        file_name_path = './faces/user/' + str(count) + '.jpg'
        cv2.imwrite(file_name_path, face)

     #Put count on images and display live count
        cv2.putText(face, str(count), (50, 50), cv2.FONT_HERSHEY_COMPLEX, 1, (0,255,0), 2)
        cv2.imshow('Face Cropper', face)
    
    else:
        print("Face not found")
        pass

    if cv2.waitKey(1) == 13 or count == 100: #13 is the Enter Key
        break
    
cap.release()
cv2.destroyAllWindows()      
print("Collecting Samples Complete")

'''