opencv 图片识别

# -*- coding: utf-8 -*-
"""
Created on Fri Nov 22 21:35:12 2019

@author: Administrator
"""

import cv2

filepath = "img/3.jpg"
img = cv2.imread(filepath) # 读取图片
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) # 转换灰色

cv2.imshow("image1", gray) # 显示图像

# OpenCV人脸识别分类器
classifier = cv2.CascadeClassifier(
r"D:BaiduNetdiskDownloadOpencvhaarcascade_frontalface_default.xml"
# "C:Python36Libsite-packagesopencv-masterdatahaarcascadeshaarcascade_frontalface_default.xml"

)
color = (0, 255, 0) # 定义绘制颜色
# 调用识别人脸
faceRects = classifier.detectMultiScale(
gray, scaleFactor=1.2, minNeighbors=3, minSize=(32, 32))
if len(faceRects): # 大于0则检测到人脸
for faceRect in faceRects: # 单独框出每一张人脸
x, y, w, h = faceRect
# 框出人脸
cv2.rectangle(img, (x, y), (x + h, y + w), color, 2)
# 左眼
cv2.circle(img, (x + w // 4, y + h // 4 + 30), min(w // 8, h // 8),
color)
#右眼
cv2.circle(img, (x + 3 * w // 4, y + h // 4 + 30), min(w // 8, h // 8),
color)
#嘴巴
cv2.rectangle(img, (x + 3 * w // 8, y + 3 * h // 4),
(x + 5 * w // 8, y + 7 * h // 8), color)

cv2.imshow("image", img) # 显示图像
c = cv2.waitKey(10)

cv2.waitKey(0)
cv2.destroyAllWindows()