如何从 BGR 框架 opencv C++ 获取红色通道

Question

    vector <Mat> sepframe;
    split(frame, sepframe );
    imshow(window_red, sepframe[2]);
    imshow(window_green, sepframe[1]);
    imshow(window_blue, sepframe[0]);

So using BGR i am able to extract channels but i imagined That while showing red channel, I will able to see atleast some red pixels. in all 3 channels, all i am seeing is Grayscale Images( since I passed only one channel Mat). Question: How to get my imagined image.

Answer 1

    vector <Mat> sepframe;
    split(frame, sepframe );
    sepframe[1]=Mat::zeros(s, sepframe[0].type());
    sepframe[0]=Mat::zeros(s, sepframe[0].type());
    Mat res;
    merge(sepframe, res);
    redVid.write(res);

here frame reading frames of original video, And i get my desired Result Thank you.!