// CPP program to detects face in a video
// Include required header files from OpenCV directory
#include "/usr/local/include/opencv2/objdetect.hpp"
#include "/usr/local/include/opencv2/highgui.hpp"
#include "/usr/local/include/opencv2/imgproc.hpp"
#include <iostream>
using namespace std;
using namespace cv;
// Function for Face Detection
void detectAndDraw( Mat& img, CascadeClassifier& cascade,
CascadeClassifier& nestedCascade, double scale );
string cascadeName, nestedCascadeName;
int main( int argc, const char** argv )
{
// VideoCapture class for playing video for which faces to be detected
VideoCapture capture;
Mat frame, image;
// PreDefined trained XML classifiers with facial features
CascadeClassifier cascade, nestedCascade;
double scale=1;
// Load classifiers from "opencv/data/haarcascades" directory
nestedCascade.load( "../../haarcascade_eye_tree_eyeglasses.xml" ) ;
// Change path before execution
cascade.load( "../../haarcascade_frontalcatface.xml" ) ;
// Start Video..1) 0 for WebCam 2) "Path to Video" for a Local Video
capture.open(0);
if( capture.isOpened() )
{
// Capture frames from video and detect faces
cout << "Face Detection Started...." << endl;
while(1)
{
capture >> frame;
if( frame.empty() )
break;
Mat frame1 = frame.clone();
detectAndDraw( frame1, cascade, nestedCascade, scale );
char c = (char)waitKey(10);
// Press q to exit from window
if( c == 27 || c == 'q' || c == 'Q' )
break;
}
}
else
cout<<"Could not Open Camera";
return 0;
}
void detectAndDraw( Mat& img, CascadeClassifier& cascade,
CascadeClassifier& nestedCascade,
double scale)
{
vector<Rect> faces, faces2;
Mat gray, smallImg;
cvtColor( img, gray, COLOR_BGR2GRAY ); // Convert to Gray Scale
double fx = 1 / scale;
// Resize the Grayscale Image
resize( gray, smallImg, Size(), fx, fx, INTER_LINEAR );
equalizeHist( smallImg, smallImg );
// Detect faces of different sizes using cascade classifier
cascade.detectMultiScale( smallImg, faces, 1.1,
2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
// Draw circles around the faces
for ( size_t i = 0; i < faces.size(); i++ )
{
Rect r = faces[i];
Mat smallImgROI;
vector<Rect> nestedObjects;
Point center;
Scalar color = Scalar(255, 0, 0); // Color for Drawing tool
int radius;
double aspect_ratio = (double)r.width/r.height;
if( 0.75 < aspect_ratio && aspect_ratio < 1.3 )
{
center.x = cvRound((r.x + r.width*0.5)*scale);
center.y = cvRound((r.y + r.height*0.5)*scale);
radius = cvRound((r.width + r.height)*0.25*scale);
circle( img, center, radius, color, 3, 8, 0 );
}
else
rectangle( img, cvPoint(cvRound(r.x*scale), cvRound(r.y*scale)),
cvPoint(cvRound((r.x + r.width-1)*scale),
cvRound((r.y + r.height-1)*scale)), color, 3, 8, 0);
if( nestedCascade.empty() )
continue;
smallImgROI = smallImg( r );
// Detection of eyes int the input image
nestedCascade.detectMultiScale( smallImgROI, nestedObjects, 1.1, 2,
0|CASCADE_SCALE_IMAGE, Size(30, 30) );
// Draw circles around eyes
for ( size_t j = 0; j < nestedObjects.size(); j++ )
{
Rect nr = nestedObjects[j];
center.x = cvRound((r.x + nr.x + nr.width*0.5)*scale);
center.y = cvRound((r.y + nr.y + nr.height*0.5)*scale);
radius = cvRound((nr.width + nr.height)*0.25*scale);
circle( img, center, radius, color, 3, 8, 0 );
}
}
// Show Processed Image with detected faces
imshow( "Face Detection", img );
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