OpenCV利用鼠标进行矩形ROI选取

#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <stdio.h>
#include <iostream>

#pragma comment(lib, "opencv_core245d.lib")
#pragma comment(lib, "opencv_highgui245d.lib")

cv::Mat matInit;
cv::Mat matSrc;
cv::Mat matDst;

cv::Rect	rectSelect;
cv::Point	ptOrigin	= cv::Point(-1, -1);
cv::Point   ptCurrent	= cv::Point(-1, -1);

std::string windowName = "orig";

void onMouse(int event, int x, int y, int flags, void *param)
{
if (matSrc.data == NULL)
return;

if (x > matSrc.cols || y > matSrc.rows)
return;

int		fontFace	= CV_FONT_HERSHEY_COMPLEX_SMALL;
double	fontScale	= 1;
int     thickness	= 1;
int     lineType	= CV_AA;

char	strTemp[16];

if (event == CV_EVENT_LBUTTONDOWN)	{

matInit.copyTo(matSrc);
matInit.copyTo(matDst);

sprintf(strTemp, "(%d,%d)",x,y);
ptOrigin = cv::Point(x, y);
rectSelect = cv::Rect(x, y, 0, 0);

cv::putText(matSrc, strTemp, ptOrigin, fontFace, fontScale,
cv::Scalar(0, 0, 0));
cv::circle(matSrc, ptOrigin, 3, cv::Scalar(0xFF, 0, 0),
CV_FILLED, lineType);

cv::imshow(windowName, matSrc);
matSrc.copyTo(matDst);

}else if (event == CV_EVENT_MOUSEMOVE &&
(flags & CV_EVENT_FLAG_LBUTTON))	{

matDst.copyTo(matSrc);

sprintf(strTemp, "(%d,%d)",x,y);
ptCurrent = cv::Point(x, y);

rectSelect.x = MIN(ptOrigin.x, ptCurrent.x);
rectSelect.y = MIN(ptOrigin.y, ptCurrent.y);
rectSelect.height = abs(ptOrigin.y - ptCurrent.y);
rectSelect.width  = abs(ptOrigin.x - ptCurrent.x);
rectSelect &= cv::Rect(0, 0, matSrc.cols, matSrc.rows);

cv::putText(matSrc, strTemp, ptCurrent, fontFace, fontScale,
cv::Scalar(0, 0, 0));
cv::rectangle(matSrc, ptOrigin, ptCurrent, cv::Scalar(0, 0xFF, 0),
thickness, lineType);
cv::imshow(windowName, matSrc);

}else if (event == CV_EVENT_LBUTTONUP)	{

sprintf(strTemp, "(%d,%d)",x,y);
ptCurrent = cv::Point(x, y);

rectSelect.x = MIN(ptOrigin.x, ptCurrent.x);
rectSelect.y = MIN(ptOrigin.y, ptCurrent.y);
rectSelect.height = abs(ptOrigin.y - ptCurrent.y);
rectSelect.width  = abs(ptOrigin.x - ptCurrent.x);
rectSelect &= cv::Rect(0, 0, matSrc.cols, matSrc.rows);

cv::putText(matSrc, strTemp, ptCurrent, fontFace, fontScale,
cv::Scalar(0, 0, 0));
cv::circle(matSrc, ptCurrent, 3, cv::Scalar(0xFF, 0, 0),
CV_FILLED, lineType);
cv::rectangle(matSrc, ptOrigin, ptCurrent, cv::Scalar(0, 0xFF, 0),
thickness, lineType);
cv::imshow(windowName, matSrc);

}

}

int main(int argc, char *argv[])
{
matInit = cv::imread("lena.jpg");
if (matInit.data == NULL)
{
std::cout << "Opening file failed!" << std::endl;
return -1;
}

matSrc = matInit.clone();
matDst = matInit.clone();

cv::namedWindow(windowName);
cv::setMouseCallback(windowName, onMouse, NULL);
cv::imshow(windowName, matSrc);

cv::waitKey(0);

return 0;
}