full body detection with c+

edit

Hi, I am new with OpenCV. I wrote a code for human full body detection, but it works not very well. Sometimes when I stay infront of camera, it does not recognise me. Maybe I done some mistakes in my code. I hope You understand me.

#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;

/** Function Headers */ 

void detectAndDisplay( Mat frame );

/** Global variables */ 
String body_cascade_name = "haarcascade_fullbody.xml";
CascadeClassifier body_cascade; 
string window_name = "Capture - Face detection"; 
RNG rng(12345);

/** @function main */
int main( int argc, const char** argv ) 
{ 
CvCapture* capture;
Mat frame;

//-- 1. Load the cascades 

if( !body_cascade.load( body_cascade_name ) )
{ 
    printf("--(!)Error loading\n"); return -1; 
};

//-- 2. Read the video stream 
capture = cvCaptureFromCAM( -1 ); 
cvSetCaptureProperty( capture, CV_CAP_PROP_FRAME_WIDTH, 180 );
cvSetCaptureProperty( capture, CV_CAP_PROP_FRAME_HEIGHT, 180 );

if( capture ) 
{ 
    while( true ) 
    { 
        frame = cvQueryFrame( capture );

        //-- 3. Apply the classifier to the frame 
        if( !frame.empty() ) 
        { 
            detectAndDisplay( frame ); 
        } else { 
            printf(" --(!) No captured frame -- Break!"); 
            break; 
        }
        int c = waitKey(100); 
        if( (char)c == 'c' ) 
        { 
            break; 
        } 
    } 
} 
return 0; 
}

/** @function detectAndDisplay */ 
void detectAndDisplay( Mat frame ) 
{ 
    vector<Rect> bodys;
    Mat frame_gray;

    cvtColor( frame, frame_gray, CV_BGR2GRAY ); 
    equalizeHist( frame_gray, frame_gray );
    //-- detect body */
    body_cascade.detectMultiScale(frame_gray, bodys, 1.1, 2, 18|9, Size(3,7));
    for( int j = 0; j < bodys.size(); j++ ) 
        { 
            Point center( bodys[j].x + bodys[j].width*0.5, bodys[j].y+ + bodys[j].height*0.5 ); 
            ellipse( frame, center, Size( bodys[j].width*0.5, bodys[j].height*0.5), 0, 0, 360, Scalar( 255, 0, 255 ), 4, 8, 0 );
        } 
    imshow( window_name, frame ); 
}