python OpenCV 人脸识别
时间: 2023-08-28 21:04:53 浏览: 45
Python中使用OpenCV库进行人脸识别的步骤如下:
1. 导入OpenCV库和需要用到的其他库:
```
import cv2
import numpy as np
```
2. 加载训练好的人脸识别模型:
```
faceCascade = cv2.CascadeClassifier("haarcascade_frontalface_default.xml")
```
3. 打开视频或者摄像头:
```
cap = cv2.VideoCapture(0)
```
4. 遍历每一帧视频或者每个摄像头捕获的图像:
```
while True:
ret, frame = cap.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
faces = faceCascade.detectMultiScale(gray, scaleFactor=1.1, minNeighbors=5, minSize=(30, 30), flags=cv2.CASCADE_SCALE_IMAGE)
```
5. 对于每个检测到的人脸,画出矩形框:
```
for (x, y, w, h) in faces:
cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
```
6. 显示视频或者摄像头捕获的图像:
```
cv2.imshow('Video', frame)
```
7. 等待退出:
```
if cv2.waitKey(1) & 0xFF == ord('q'):
break
```
8. 释放资源:
```
cap.release()
cv2.destroyAllWindows()
```
完整代码:
```
import cv2
import numpy as np
faceCascade = cv2.CascadeClassifier("haarcascade_frontalface_default.xml")
cap = cv2.VideoCapture(0)
while True:
ret, frame = cap.read()
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
faces = faceCascade.detectMultiScale(gray, scaleFactor=1.1, minNeighbors=5, minSize=(30, 30), flags=cv2.CASCADE_SCALE_IMAGE)
for (x, y, w, h) in faces:
cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 255, 0), 2)
cv2.imshow('Video', frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
cv2.destroyAllWindows()
```