http://blog.csdn.net/xiaowei_cqu/article/details/7829481
#include "stdafx.h"
#include // va_list, va_start, va_arg, va_end 
#include
#include
#include
#include
#include
#include
#include
using namespace std;
using namespace cv;


// Global variables
bool is_drawing=false;
vector biaozhu_boxs;
Rect drawing_box;
Mat img_original,img_drawing;
//! assigns callback for mouse events




static void help()
{
cout << "This program designed for labeling video \n"
<<"Coded by L. Wei on 9/4/2013\n"<
cout<<"Use the mouse to draw rectangle on the image for labeling.\n"<

cout << "Hot keys: \n"
"\tESC - quit the program\n"
"\tn - next frame of the video\n"
"\tz - undo the last label\n"
"\tc - clear all the labels\n"
< }


static void onMouse( int event, int x, int y, int, void* )
{
switch(event)
{
case CV_EVENT_LBUTTONDOWN: 
//the left up point of the rect
is_drawing=true;
drawing_box.x=x;
drawing_box.y=y;
break;
case CV_EVENT_MOUSEMOVE:
//adjust the rect (use color blue for moving)
if(is_drawing){
drawing_box.width=x-drawing_box.x;
drawing_box.height=y-drawing_box.y;
img_original.copyTo(img_drawing);
for(vector::iterator it=biaozhu_boxs.begin();
it!=biaozhu_boxs.end();++it){
rectangle(img_drawing,(*it),Scalar(0,255,0));
}
rectangle(img_drawing,drawing_box,Scalar(255,0,0));
}
break;
case CV_EVENT_LBUTTONUP:
//finish drawing the rect (use color green for finish)
if(is_drawing){
drawing_box.width=x-drawing_box.x;
drawing_box.height=y-drawing_box.y;
img_original.copyTo(img_drawing);
for(vector::iterator it=biaozhu_boxs.begin();
it!=biaozhu_boxs.end();++it){
rectangle(img_drawing,(*it),Scalar(0,255,0));
}
rectangle(img_drawing,drawing_box,Scalar(0,255,0));
biaozhu_boxs.push_back(drawing_box);
}
is_drawing=false;
break;
}
imshow("Video",img_drawing);
return;
}




int main(){
namedWindow("Video");
ofstream outfile("a.txt");
help();
VideoCapture capture("test.avi");
capture>>img_original;
img_original.copyTo(img_drawing);
for(vector::iterator it=biaozhu_boxs.begin();
it!=biaozhu_boxs.end();++it){
rectangle(img_drawing,(*it),Scalar(0,255,0));
}
imshow("Video",img_original);
cvSetMouseCallback( "Video", onMouse, 0 );


int frame_counter=0;


while(1){
int c=waitKey(0);
if( (c & 255) == 27 )
{
cout << "Exiting ...\n";
break;
}
switch((char)c)
{
case 'n':
//read the next frame
++frame_counter;
capture>>img_original;
if(img_original.empty()){
cout<<"\nVideo Finished!"< return 0;
}


img_original.copyTo(img_drawing);
//save all of the labeling rects
for(vector::iterator it=biaozhu_boxs.begin();
it!=biaozhu_boxs.end();++it){
rectangle(img_drawing,(*it),Scalar(0,255,0));
outfile< <<(*it).y<<" "<<(*it).width<<" "
<<(*it).height< }
break;
case 'z':
//undo the latest labeling
if(!biaozhu_boxs.empty()){
vector::iterator it_end=biaozhu_boxs.end();
--it_end;
biaozhu_boxs.erase(it_end);
}
img_original.copyTo(img_drawing);
for(vector::iterator it=biaozhu_boxs.begin();
it!=biaozhu_boxs.end();++it){
rectangle(img_drawing,(*it),Scalar(0,255,0));
}
break;
case 'c':
//clear all the rects on the image
biaozhu_boxs.clear();
img_original.copyTo(img_drawing);
}


imshow("Video",img_drawing);
}


return 0;
}