如何在这样的视频上选择感兴趣的区域

Posted 2021-04-16

我正在进行队列旁路检测项目，我需要选择一个感兴趣的区域或边界。如果一个人越过边界，我们应该得到警报。请帮我在实时视频中选择一个感兴趣的区域，类似于图像中的区域。

please see this image

答案

在做了一些研究后，我发现了你需要的github

#include "opencv2/opencv.hpp" 
#include <iostream>

using namespace cv;
using namespace std;

/*~~~~~~~~~~~~~~~~~~*/
char ky;
bool got_roi = false;
Point points_array[4];
Mat src, ROI_Img,backup,ROI_MASK;
Rect2d ROI_Select;
int width_roi = 0, height_roi = 0,min_x,min_y,max_x,max_y;
Rect ROI_RECT ;
vector< vector<Point> >  co_ordinates;
/*~~~~~~~~~~~~~~~~~~*/


/*~~~~~~~~~~~~~~~~~~*/
//Callback for mousclick event, the x-y coordinate of mouse button-down 
//are stored array of points [points_array].

void mouse_click(int event, int x, int y, int flags, void *param)
{

static int count=0;
    switch (event)
    {
    case CV_EVENT_LBUTTONDOWN:
        {
        switch (count)  // number of set Point 
            {
                case 0:
                    cout << "Select top-right    point" << endl;
                break;
            case 1:
                cout << "Select bottom-right point" << endl;
                break;
            case 2:
                cout << "Select bottom-left  point" << endl << endl;
                break;
            default:
                break;
        }

        if (!got_roi) // you are not select ROI yet!
        {
            points_array[count] = Point(x,y);
            circle(src, points_array[count], 2, Scalar(0, 255, 0), 2);  //show points on image
            imshow("My_Win", src);
            count++;
            if (count == 4) // if select 4 point finished
            {
                cout << "ROI x & y points :" << endl;
                cout << points_array[0] << endl;
                cout << points_array[1] << endl;
                cout << points_array[2] << endl;
                cout << points_array[3] << endl;
                cout << endl << "ROI Saved You can continue with double press any keys except 'c' " << endl <<"once press 'c' or 'C' to clear points and retry select ROI " << endl << endl;
                ky = waitKey(0) & 0xFF;

                if (ky == 99 || ky == 67)  // c or C to clear
                {
                    backup.copyTo(src);
                    points_array[0] = Point(0, 0);
                    points_array[1] = Point(0, 0);
                    points_array[2] = Point(0, 0);
                    points_array[3] = Point(0, 0);
                    imshow("My_Win", src);
                    count = 0;
                    cout << endl << endl << endl << "@---------------------  Clear Points!  ------------------@ " << endl << endl << endl  ;
                }
                else // user accept points & dosn't want to clear them
                {
                    min_x = std::min(points_array[0].x, points_array[3].x); //find rectangle for minimum ROI surround it!
                    max_x = std::max(points_array[1].x, points_array[2].x);
                    min_y = std::min(points_array[0].y, points_array[1].y);
                    max_y = std::max(points_array[3].y, points_array[2].y);
                    height_roi = max_y - min_y;
                    width_roi = max_x - min_x;
                    ROI_RECT = Rect(min_x, min_y, width_roi, height_roi);
                    got_roi = true;
                    co_ordinates.push_back(vector<Point>());
                    co_ordinates[0].push_back(points_array[0]);
                    co_ordinates[0].push_back(points_array[1]);
                    co_ordinates[0].push_back(points_array[2]);
                    co_ordinates[0].push_back(points_array[3]);

                    }
                }
            }
            else { // if got_roi se true => select roi before
                cout << endl << "You Select ROI Before " << endl << "if you want     to clear point press 'c' or double press other keys to continue" << endl <<     endl;
            }
            break;
        }
    }

}
/*~~~~~~~~~~~~~~~~~~*/

int main()
{
    // replace all "My_Win" with your window name
    /*~~~~~~~~~~~~~~~~~~*/
    namedWindow("My_Win", 1);
    /*~~~~~~~~~~~~~~~~~~*/

    VideoCapture input_video("Video_path");

    // Set source imafe as [src]
    /*~~~~~~~~~~~~~~~~~~*/
    input_video >> src;
    imshow("My_Win", src);
    src.copyTo(backup);
    setMouseCallback("My_Win", mouse_click, 0);
    waitKey(0);
    Mat mask(src.rows, src.cols, CV_8UC1, cv::Scalar(0));
    drawContours(mask, co_ordinates, 0, Scalar(255), CV_FILLED, 8);
    /*~~~~~~~~~~~~~~~~~~*/

    while (1)
    {
        input_video >> src;

        /*~~~~~~~~~~~~~~~~~~*/  
        //Need to copy Select ROI as MASK
        src.copyTo(ROI_MASK, mask);
        //Creat a rectangle around the Mask to reduce size of mask
        ROI_Img = ROI_MASK(ROI_RECT);
        /*~~~~~~~~~~~~~~~~~~*/

        //Show Image
        imshow("My_Win", ROI_Img);

        // Do remaining processing here on capture roi for every frame
        if(char (waitKey(1)& 0xFF) == 27) break;


    }
}