人脸识别(三)
3.1 准备工作
其实和之前用C++实现人脸识别的准备工作差不多,而且还更方便。
- 会自动开启本地摄像头,不必添加别的文件;
- 如果之前下载安装了opencv3,这里直接导入就好。有时
import cv2
可能会提示No module named cv2
,这时选择install package opencv-pyhton
就好; - xml文档还是要导入的,下载到项目文件夹就好;
3.2 代码
代码注释还是比较详细的,不需再多说什么了。有不好的地方欢迎评论提出。
# -*- coding: utf-8 -*-
# @Author 作者 : BogeyDa!!
# @FileName 文件名 : FaceDetect_py.py
# @Software 创建文件的IDE : PyCharm
# @Blog 博客地址 : https://blog.youkuaiyun.com/lrglgy
# @Time 创建时间 : 2019-05-06 11:42
#
# @reference参考 : 代码:https://github.com/spmallick/learnopencv/blob/master/FaceDetectionComparison/face_detection_dlib_hog.py#L48
# 博客:https://www.learnopencv.com/face-detection-opencv-dlib-and-deep-learning-c-python/
# @Log 代码说明:利用Haar特征对面部进行识别,代码成功运行
from __future__ import division
import cv2
import time
import sys
def detectFaceOpenCVHaar(faceCascade, frame, inHeight=300, inWidth=0):
# 修改帧大小为高度300,宽度据情况而变(frameWidth/frameHeight)* inHeight
# 这里只是对帧大小进行调整,但还未真正落实
frameOpenCVHaar = frame.copy()
frameHeight = frameOpenCVHaar.shape[0]
frameWidth = frameOpenCVHaar.shape[1]
if not inWidth:
inWidth = int((frameWidth / frameHeight) * inHeight)
# 获取高度和宽度的缩放比例
scaleHeight = frameHeight / inHeight
scaleWidth = frameWidth / inWidth
# 将帧进行缩放,真正落实帧的改变frameOpenCVHaarSmall,并将帧灰度化frameGray,但原始帧frameOpenCVHaar并未改变
frameOpenCVHaarSmall = cv2.resize(frameOpenCVHaar, (inWidth, inHeight))
frameGray = cv2.cvtColor(frameOpenCVHaarSmall, cv2.COLOR_BGR2GRAY)
# 利用Haar探测器找到人脸并在原始帧上框出来
faces = faceCascade.detectMultiScale(frameGray)
bboxes = []
for (x, y, w, h) in faces:
x1 = x
y1 = y
x2 = x + w
y2 = y + h
cvRect = [int(x1 * scaleWidth), int(y1 * scaleHeight),
int(x2 * scaleWidth), int(y2 * scaleHeight)]
bboxes.append(cvRect)
# 框出人脸,参数依次表示被识别帧、框一角的坐标、框另一角坐标、框的颜色、框宽度、框类型
# 参考:[python opencv cv2.rectangle 參數含義](https://www.twblogs.net/a/5c22417dbd9eee16b3daf922)
cv2.rectangle(frameOpenCVHaar, (cvRect[0], cvRect[1]), (cvRect[2], cvRect[3]), (0, 255, 0),
int(round(frameHeight / 150)), 4)
return frameOpenCVHaar, bboxes
# 从命令行读取参数,即获取要进行面部识别的文件
# 加载Haar特征,Harr特征文件可根据自身需求导入不同文件,文件链接:https://github.com/opencv/opencv/tree/master/data/haarcascades
if __name__ == "__main__":
source = 0
if len(sys.argv) > 1:
source = sys.argv[1]
# haarcascade_frontalface_default.xml is in models directory.
faceCascade = cv2.CascadeClassifier('model/haarcascade_frontalface_default.xml')
# faceCascade = cv2.CascadeClassifier('./haarcascade_frontalface_default.xml')
# 读取进行识别的文件,source表示文件路径,当为0时打开本地摄像头
# hasFrame表示是否读取到图片,frame表示读取到的每一帧图片
cap = cv2.VideoCapture(source)
hasFrame, frame = cap.read()
# 参考:[OpenCV学习笔记(四十七)——VideoWriter生成视频流highgui](https://blog.youkuaiyun.com/yang_xian521/article/details/7440190)
# 使用video_writer类,将图片序列保存为视频文件,参数依次为视频文件名、视频编码格式、帧速率、帧大小
vid_writer = cv2.VideoWriter('output-haar-{}.avi'.format(str(source).split(".")[0]),
cv2.VideoWriter_fourcc('M', 'J', 'P', 'G'), 15, (frame.shape[1], frame.shape[0]), False)
# vid_writer = cv2.VideoWriter('output-haar-test.avi',
# cv2.VideoWriter_fourcc('M', 'J', 'P', 'G'), 15, (frame.shape[1], frame.shape[0]),
# False)
# 读取并保存摄像头中的每一帧至frame
frame_count = 0
tt_opencvHaar = 0
while (1):
hasFrame, frame = cap.read()
if not hasFrame:
break
frame_count += 1
# 获取摄像头拍摄时的帧速率,而VideoWriter中的帧速率15表示存入视频的帧速率
# 利用Haar探测器探测人脸并框出
t = time.time()
outOpencvHaar, bboxes = detectFaceOpenCVHaar(faceCascade, frame)
tt_opencvHaar += time.time() - t
fpsOpencvHaar = frame_count / tt_opencvHaar
label = "OpenCV Haar ; FPS : {:.2f}".format(fpsOpencvHaar)
cv2.putText(outOpencvHaar, label, (10, 50), cv2.FONT_HERSHEY_SIMPLEX, 1.4, (0, 0, 255), 3, cv2.LINE_AA)
cv2.imshow("Face Detection Comparison", outOpencvHaar)
vid_writer.write(outOpencvHaar)
if frame_count == 1:
tt_opencvHaar = 0
key = cv2.waitKey(1) & 0xFF
# click keyboard 'q' to exit
if key == ord("q"):
break
cv2.destroyAllWindows()
vid_writer.release()
项目文件目录如下图:
3.3 使用
- IDE(Pycharm等)
直接点击运行按钮,会打开本地摄像头。 - Terminal(终端)
如下图所示:
3.3 结果
当未指定文件时,本地摄像头会自动打开,摄像头影像中的人脸会被自动识别框出,同时左上角会显示当前帧频率,停止运行程序后,人脸识别视频会被保存至本地,并命名为output-haar-0.avi
。
当指定文件后,会打开指定的本地视频并识别其中的人脸,然后保存视频到本地。