opencv学习-Cascade Classifier-人脸人眼识别

CascadeClassifier类中的函数如下：

1 empty判断分类器是否加载成功；

2 load加载训练好的xml文件；

3 read读取xml文件；

4 detectMultiScale多尺度检测目标，返回一系列矩形；C++: void CascadeClassifier::detectMultiScale(const
Mat& image, vector<Rect>& objects,
double scaleFactor=1.1, intminNeighbors=3,
int flags=0, Size minSize=Size(),
Size maxSize=Size())

5 setImage设定检测图片；

[b]6 runAt制定从哪点开始检测；

[/b]

例子如下：

#include <stdio.h>
#include <iostream>
#include "opencv2/core/core.hpp"
#include "opencv2/objdetect/objdetect.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>
using namespace std;
using namespace cv;
void detectAndDisplay( Mat frame );
/** Global variables */
String face_cascade_name = "haarcascade_frontalface_alt.xml";
String eyes_cascade_name = "haarcascade_eye_tree_eyeglasses.xml";
CascadeClassifier face_cascade;
CascadeClassifier eyes_cascade;
string window_name = "Capture - Face detection";
RNG rng(12345);
/** @function main */
int main( int argc, char** argv )
{
VideoCapture cam("3.avi");
if (!face_cascade.load(face_cascade_name))
{
printf("--(!)Error loading\n");
return -1;
}
if (!eyes_cascade.load(eyes_cascade_name))
{
printf("--(!)Error loading\n");
return -1;
}
Mat frame;
while (true)
{
if (cam.isOpened())
{
//frame=cvQueryFrame(cam);
cam>>frame;
if( !frame.empty() )
{ detectAndDisplay( frame ); }
else
{ printf(" --(!) No captured frame -- Break!"); break; }

int c = waitKey(10);
if( (char)c == 'c' ) { break; }

}
}
}
void detectAndDisplay( Mat frame )
{
vector<Rect>faces;
Mat frame_gray;
cvtColor(frame,frame_gray,CV_BGR2GRAY);
equalizeHist(frame_gray,frame_gray);
face_cascade.detectMultiScale(frame_gray,faces,1.1,2,0, Size(30, 30) );
for (int i=0;i<faces.size();i++)
{
Point center(faces[i].x+faces[i].width*0.5,faces[i].y+faces[i].height*0.5);
ellipse(frame,center,Size( faces[i].width*0.5, faces[i].height*0.5), 0, 0, 360, Scalar( 255, 0, 255 ), 4, 8, 0);
Mat faceROI = frame_gray( faces[i] );
std::vector<Rect> eyes;
//-- In each face, detect eyes
eyes_cascade.detectMultiScale( faceROI, eyes, 1.1, 2, 0 , Size(30, 30) );
for( int j = 0; j < eyes.size(); j++ )
{
Point center( faces[i].x + eyes[j].x + eyes[j].width*0.5, faces[i].y + eyes[j].y + eyes[j].height*0.5 );
int radius = cvRound( (eyes[j].width + eyes[j].height)*0.25 );
circle( frame, center, radius, Scalar( 255, 0, 0 ), 4, 8, 0 );
}
}
imshow(window_name, frame);

}