opencv图像处理之鼠标事件（矩形roi绘图）

为满足图像处理要求，博主写此简易代码有如下作用：

1、根据感兴趣区域做深度学习标签；

2、提取感兴趣区域进行目标跟踪；

3、对感兴趣区域进行进一步操作。

具体代码如下：

//Author: samylee
//Contact email: ahuljx@126.com
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <stdio.h>

using namespace cv;

Mat org, dst, img, tmp;

void on_mouse(int event, int x, int y, int flags, void *ustc)
{
static Point pre_pt = (-1, -1);
static Point cur_pt = (-1, -1);
if (event == CV_EVENT_LBUTTONDOWN)
{
org.copyTo(img);
pre_pt = Point(x, y);
}
else if (event == CV_EVENT_MOUSEMOVE && (flags & CV_EVENT_FLAG_LBUTTON))//摁下左键，flags为1
{
img.copyTo(tmp);
cur_pt = Point(x, y);
rectangle(tmp, pre_pt, cur_pt, Scalar(0, 255, 0, 0), 1, 8, 0);
imshow("img", tmp);
}
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);
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("desktop.jpg");
org.copyTo(img);
namedWindow("img");
setMouseCallback("img", on_mouse, 0);
imshow("img", img);
waitKey(0);
}

效果图如下：

处理前：



处理后：



任何问题请加唯一QQ2258205918（名称samylee）！