- 选取图像中的ROI区域:
#include<opencv2\opencv.hpp>
#include <stdio.h>
using namespace cv;
Mat org, dst, img, tmp;
void on_mouse(int event, int x, int y, int flags, void *)
{
static Point pre_pt = (-1, -1);
static Point cur_pt = (-1, -1);
if (event == CV_EVENT_LBUTTONDOWN)
{
pre_pt = Point(x, y);
}
else if (event == CV_EVENT_MOUSEMOVE && flags)//摁下左键,flags为1
{
org.copyTo(tmp);
cur_pt = Point(x, y);
rectangle(tmp, pre_pt, cur_pt, Scalar(0, 255, 0, 0), 1, 8, 0);
imshow("img", tmp);//画的时候显示框
}
else if (event == CV_EVENT_LBUTTONUP)
{
org.copyTo(img);
//cur_pt = Point(x, y);
rectangle(img, pre_pt, cur_pt, Scalar(0, 255, 0, 0), 1, 8, 0);
imshow("img", img);//画完后显示框
//img.copyTo(tmp);
int width = abs(pre_pt.x - cur_pt.x);
int height = abs(pre_pt.y - cur_pt.y);
if (width == 0 || height == 0)
{
return;
}
dst = org(Rect(min(cur_pt.x, pre_pt.x), min(cur_pt.y, pre_pt.y), width, height));
namedWindow("dst");
imshow("dst", dst);
}
}
void main()
{
org = imread("123.jpg");
org.copyTo(img);
namedWindow("img");
setMouseCallback("img", on_mouse, 0);
imshow("img", img);
waitKey(0);
}