cpp:1389 错误断言在人脸检测中检测多尺度失败

如何解决cpp:1389 错误断言在人脸检测中检测多尺度失败

错误：OpenCV(4.5.1) /tmp/pip-req-build-tk9iuyva/opencv/modules/objdetect/src/cascadedetect.cpp:1389: 错误: (-215:Assertion failed) scaleFactor > 1 && _image .depth() == CV_8U 函数'detectMultiScale'

我尝试添加 gray = np.array(gray,dtype='uint8') 并且错误消失了但是检测人脸时应该出现的框没有出现

import tensorflow as tf
import keras
from tensorflow.keras.applications.mobilenet_v2 import preprocess_input
from tensorflow.keras.preprocessing.image import img_to_array
from tensorflow.keras.preprocessing.image import load_img
import numpy as np
import argparse 
import cv2
import os
import matplotlib.pyplot as plt
%matplotlib inline  

model = tf.keras.models.load_model("../input/modelh5/My_Model.h5")
images=['../input/face-mask1/examples/example_01.png','../input/face-mask1/examples/example_02.png','../input/face-mask1/examples/example_03.png' ]
face_cascade = cv2.CascadeClassifier('../input/haarcascade/haarcascade_frontalface_default.xml')

  

img = images[0]    # Add path here
    
img = plt.imread(img,format='8UC1')
gray = cv2.cvtColor(img,cv2.COLOR_RGB2GRAY)

faces = face_cascade.detectMultiScale(gray,1.3,5)

# Draw the rectangle around each face
for (x,y,w,h) in faces:

    face = img[y:y+h,x:x+w]
    face = cv2.resize(face,(224,224))
    face = img_to_array(face)
    face = preprocess_input(face)
    face = np.expand_dims(face,axis=0)
    (mask,withoutMask) = model.predict(face)[0]
    mask = mask*100
    withoutMask = withoutMask*100
    
    font = cv2.FONT_HERSHEY_SIMPLEX
    
    # Getting Text Size in pixel
    print("Image Width: ",w)
    textSize = cv2.getTextSize(text="No Mask: " + str("%.2f" % round(mask,2)),fontFace=cv2.FONT_HERSHEY_SIMPLEX,fontScale=1,thickness=3)
    print("Text Width: ",textSize[0][0])
    
    if mask > withoutMask:
        cv2.putText(img,text = "Mask: " + str("%.2f" % round(mask,org = (x-5,y-15),fontFace=font,fontScale = (2*w)/textSize[0][0],color = (0,255,0),thickness = 3,lineType = cv2.LINE_AA)
        cv2.rectangle(img,(x,y),(x+w,y+h),(0,5)
    else:
        cv2.putText(img,text = "No Mask: " + str("%.2f" % round(withoutMask,fontScale = (1.8*w)/textSize[0][0],color = (255,(255,5)

# Display
plt.imshow(img)
img = cv2.cvtColor(img,cv2.COLOR_BGR2RGB)