Question

我正在尝试使用 python 检测照片中的人脸

# Import the excel file available
import os
import numpy as np, pandas as pd
import warnings
from PIL import Image 
import matplotlib.pyplot as plt
import cv2
warnings.filterwarnings('ignore')

假设我有照片目录并且它存储在 pic_loc

# Load in color image for face detection
image = cv2.imread(pic_loc)

# Convert the image to RGB colorspace
image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)

# Make a copy of the original image to draw face detections on
image_copy = np.copy(image)

# Convert the image to gray 
gray_image = cv2.cvtColor(image, cv2.COLOR_RGB2GRAY)

# Detect faces in the image using pre-trained face dectector
faces = face_cascade.detectMultiScale(gray_image, 1.25, 6)

我在最后一点收到一个错误，它必须是一些错误

Answer 1

您需要创建一个 cv2.CascadeClassifier() 对象。

<CascadeClassifier object>  =   cv2.CascadeClassifier(  filename    )

CV2 Documentation

这是一个小例子：

import numpy as np
import cv2
from matplotlib import pyplot as plt

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
eye_cascade = cv2.CascadeClassifier('haarcascade_eye.xml')

img = cv2.imread('xyzjpg')
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

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


for (x,y,w,h) in faces:
    cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)
    roi_gray = gray[y:y+h, x:x+w]
    roi_color = img[y:y+h, x:x+w]
    eyes = eye_cascade.detectMultiScale(roi_gray)
    for (ex,ey,ew,eh) in eyes:
        cv2.rectangle(roi_color,(ex,ey),(ex+ew,ey+eh),(0,255,0),2)

cv2.imshow('img',img)
cv2.waitKey(0)
cv2.destroyAllWindows()

Answer 2

我真的很想感谢@Divyansh Chaudhary，但提供的解决方案并没有完全解决我的问题。诀窍是重新定义

face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_frontalface_default.xml')
eye_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_eye.xml')

唯一解决它的是以下。

# Import the excel file available
import os
import numpy as np, pandas as pd
import warnings
from PIL import Image 
import matplotlib.pyplot as plt
import cv2
warnings.filterwarnings('ignore')

然后使用您可以执行的图像目录

# Load in color image for face detection
image = cv2.imread(pic_loc)

# Convert the image to RGB colorspace
image = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)

# Make a copy of the original image to draw face detections on
image_copy = np.copy(image)

# Convert the image to gray 
gray_image = cv2.cvtColor(image, cv2.COLOR_RGB2GRAY)


face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_frontalface_default.xml')
eye_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + 'haarcascade_eye.xml')

# Detect faces in the image using pre-trained face dectector
faces = face_cascade.detectMultiScale(gray_image, 1.25, 6)

NameError: name 'face_cascade' 未定义

2 个答案: