opencv图像及视频感兴趣区域设置

之前学过的简单绘图方法，例如矩形，椭圆等，今天试着在视频图像中用矩形标注感兴趣区域（ROI）

<----图像篇---->

#include "opencv2/core/core.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <iostream>
using namespace std;
using namespace cv;

bool draw;
Mat src;//原始图像
Mat roi;//ROI图像
Point cursor;//初始坐标
Rect rect;//标记ROI的矩形框

void onMouse(int event, int x, int y, int flags, void *param)
{
    Mat img = src.clone();
    switch (event)
    {
    //按下鼠标左键,点击鼠标图像时，清除之前ROI图像的显示窗口
    case CV_EVENT_LBUTTONDOWN:
        cvDestroyWindow("ROI");
        //存放起始坐标
        cursor = Point(x, y);
        //初始化起始矩形框
        rect = Rect(x, y, 0, 0);
        draw = true;
        break;
    //松开鼠标左键
    case CV_EVENT_LBUTTONUP:
        if (rect.height > 0 && rect.width > 0)
        {
            roi = img(Rect(rect.x, rect.y, rect.width, rect.height));
            rectangle(img, rect, Scalar(255, 255, 255),2);
            namedWindow("SignROI");
            imshow("SignROI", img);  

            //将画过矩形框的图像用原图像还原
            src.copyTo(img);
            imshow("SrcImage", img);  

            //显示ROI图像
            namedWindow("ROI");
            imshow("ROI", roi);
            waitKey(0);
        }
        draw = false;
        break;
    //移动光标
    case CV_EVENT_MOUSEMOVE:
        if (draw)
        {
            //用MIN得到左上点作为矩形框的起始坐标，如果不加这个，画矩形时只能向一个方向进行
            rect.x = MIN(x, cursor.x);
            rect.y = MIN(y, cursor.y);
            rect.width = abs(cursor.x - x);
            rect.height = abs(cursor.y - y);
            //防止矩形区域超出图像的范围
            rect &= Rect(0, 0, src.cols, src.rows);
        }
        break;
    }
}  

int main()
{
    src=imread("E://IM_VIDEO//kobe.jpg");
    if(src.data==0)
    {
        cout<<"the src image is not built!"<<endl;
        return -1;
    }
    namedWindow("SrcImage");
    imshow("SrcImage",src);
    setMouseCallback("SrcImage", onMouse, NULL);
    waitKey();
    return 0;
}

运行结果如下：

<---视频篇--->

#include<opencv2\core\core.hpp>
#include<opencv2\highgui\highgui.hpp>
#include<opencv2\imgproc\imgproc.hpp>
#include<iostream>
#include<vector>
using namespace cv;
using namespace std;  

bool drawing_box = false;
bool gotBox =  false;
Rect box;
Point downPoint;  

void mouseRectHandler(int event, int x, int y, int flags, void *param)
{
    switch (event)
    {
    case CV_EVENT_MOUSEMOVE:
        if (drawing_box)
        {
            //鼠标的移动到downPoint的右下角
            if( x >=downPoint.x && y >= downPoint.y)
            {
                box.x = downPoint.x;
                box.y = downPoint.y;
                box.width = x - downPoint.x;
                box.height =  y -  downPoint.y;
            }
            //鼠标的移动到downPoint的右上角
            if( x >= downPoint.x && y <= downPoint.y)
            {
                box.x =  downPoint.x;
                box.y = y;
                box.width = x - downPoint.x;
                box.height = downPoint.y - y;
            }
            //鼠标的移动到downPoint的左上角
            if( x <= downPoint.x && y <= downPoint.y)
            {
                box.x = x;
                box.y = y;
                box.width = downPoint.x - x;
                box.height = downPoint.y - y;
            }
            //鼠标的移动到downPoint的左下角
            if( x <= downPoint.x && y >= downPoint.y)
            {
                box.x = x;
                box.y = downPoint.y;
                box.width = downPoint.x -x;
                box.height = y - downPoint.y;
            }
        }
        break;  

    case CV_EVENT_LBUTTONDOWN:
        drawing_box = true;
        //起点
        downPoint = Point(x,y);
        break;  

    case CV_EVENT_LBUTTONUP:
       //松开鼠标，结束画矩形
        drawing_box = false;
        gotBox = true;
        break;
    default:
        break;
    }
}  

int main(int argc,char*argv[])
 {
     VideoCapture video("E://IM_VIDEO//xxx.mp4");
     if( !video.isOpened())
         return 0;
     Mat frame;
     namedWindow("face",1);
     setMouseCallback("face",mouseRectHandler,NULL);    

     //画感兴趣区域
    for(;;)
     {
        video>>frame;
        if(!frame.data)
            break;
         rectangle(frame,box,Scalar(255,255,255),2);//参见绘图介绍
         imshow("face",frame);
        if(waitKey(50) == ‘c‘)
            break;
     }    

     return 0;
 }    

运行结果如下：

参考：

http://blog.csdn.net/zhangping1987/article/details/51880098

http://blog.csdn.net/qq_23968185/article/details/51335291