编写并显示图像OpenCV

Question

I am recording a video footage and preforming various image processing methods on each frame to obtain desired result.

Now once I get the result I am looking for i want to capture and store a particular frame on my hdd.

To do this I am using imwrite function to write the frame as a jpg. then I use imshow to display this frame in a namesWindow.

The problem is that when all the conditions are meet to store the image my program instead of storing the image, gives me a run time error.......

Here is the code:

for(vector<double>::iterator iter_dis = Left_Point_distance.begin(); iter_dis != Left_Point_distance.end();++iter_dis)
    {


        if(*iter_dis > 20 && center.y >= 120 && center.x >=510 && Box[0].width > Box[0].height)
        {

            char* window_Punches = "Punches";
            namedWindow(window_Punches ,1);

            Mat Hook;

            imwrite("C:\\Hook.jpg", Hook);
            imshow(window_Punches, Hook);


        }


        if(*iter_dis >20 && center.y <=60)
        {

        }

    }

Going through opencv tutorials This is how this how its done but in my case is not working......

Further more all the process takes place in a infinite while loop, and videoframes are stored in Mat frame; which is then displayed in a window using imshow function.

Can anybody spot what am doing wrong here....?

Answer 1

您定义了Mat Hook，但是在尝试使用imwrite（）编写时为空

Answer 2

What do you expect from this code:

  Mat Hook;

  imwrite("C:\\Hook.jpg", Hook);
  imshow(window_Punches, Hook);

You create an empty matrix and use it.