http://study.marearts.com/2014/09/opencv-face-detection-using-adaboost.html
#include < iostream>
#include "opencv2\objdetect\objdetect.hpp"
#include "opencv2\highgui\highgui.hpp"
#include "opencv2\imgproc\imgproc.hpp"
#include "opencv2\cudaobjdetect.hpp"
#include "opencv2\cudaimgproc.hpp"
#ifdef _DEBUG
#pragma comment(lib, "opencv_core300d.lib")
#pragma comment(lib, "opencv_highgui300d.lib")
#pragma comment(lib, "opencv_imgcodecs300d.lib")
#pragma comment(lib, "opencv_objdetect300d.lib")
#pragma comment(lib, "opencv_imgproc300d.lib")
#pragma comment(lib, "opencv_cudaobjdetect300d.lib")
#else
#pragma comment(lib, "opencv_core300.lib")
#pragma comment(lib, "opencv_highgui300.lib")
#pragma comment(lib, "opencv_imgcodecs300.lib")
#pragma comment(lib, "opencv_objdetect300.lib")
#pragma comment(lib, "opencv_imgproc300.lib")
#pragma comment(lib, "opencv_cudaobjdetect300.lib")
#endif
using namespace std;
using namespace cv;
void main()
{
//for time measure
float TakeTime;
unsigned long Atime, Btime;
//window
namedWindow("origin");
//load image
Mat img = imread("sh.jpg");
Mat grayImg; //adaboost detection is gray input only.
cvtColor(img, grayImg, CV_BGR2GRAY);
//load xml file
string trainface = ".\\haarcascade_frontalface_alt.xml";
//declaration
Ptr< cuda::CascadeClassifier> cascade_gpu = cuda::CascadeClassifier::create(trainface);
/////////////////////////////////////////////
//gpu case face detection code
cuda::GpuMat faceBuf_gpu;
cuda::GpuMat GpuImg;
vector< Rect> faces;
GpuImg.upload(grayImg);
Atime = getTickCount();
cascade_gpu->detectMultiScale(GpuImg, faceBuf_gpu);
cascade_gpu->convert(faceBuf_gpu, faces);
Btime = getTickCount();
TakeTime = (Btime - Atime) / getTickFrequency();
printf("detected face(gpu version) =%d / %lf sec take.\n", faces.size(), TakeTime);
Mat faces_downloaded;
if (faces.size() >= 1)
{
for (size_t i = 0; i < faces.size(); ++i)
rectangle(img, faces[i], Scalar(255));
}
/////////////////////////////////////////////////
//result display
imshow("origin", img);
waitKey(0);
}
