飞龙绣球3.0--split()通道分离

相对于之前使用inrange()函数的的两篇文章，这篇使用了通道相减的方式，来确定目标的颜色，也算是一个比较简单的方法吧，

免去了一直修改颜色参数的问题，后期的准确度就是靠对图像的优化和处理所决定的
放代码

Mat picture, Dealed_pict,Bright_pict;
vectorchannels;
int BrightValue = 80;
vector > contours;
vector hierarchy;


int main()
{
    namedWindow("识别颜色", WINDOW_NORMAL);
    VideoCapture capture(0);
    while (1)
    {
        capture >> picture;
        split(picture, channels);
        Dealed_pict = channels.at(2) - channels.at(0);
        threshold(Dealed_pict, Dealed_pict, 120, 255, THRESH_BINARY);
        Mat element = getStructuringElement(MORPH_ELLIPSE,Size(4,4));
        dilate(Dealed_pict, Dealed_pict, element);
        vector > contours;
        vector hierarchy;
        findContours(Dealed_pict, contours, hierarchy, RETR_CCOMP, CHAIN_APPROX_SIMPLE);
        RotatedRect box;
        double area = 0;
        for (int i = 0; i < contours.size(); i++)
        {
            if (contourArea(contours[i]) > area)
            {
                area = contourArea(contours[i]);
                box = minAreaRect(contours[i]);
            }
        }
        Point2f vertex[4];
        box.points(vertex);
        for (int i = 0; i < 4; i++)
        {
            line(picture, vertex[i], vertex[(i + 1) % 4], Scalar(100, 200, 300), 2, LINE_AA);
        }
        imshow("识别颜色", Dealed_pict);
        imshow("原图",picture);
        waitKey(1);
    }
    return 0;
}