opencv HSV找颜色，找轮廓用最小旋转矩形框出

#include <opencv2/opencv.hpp>
#include<iostream>
#include<string>
using namespace cv;
using namespace std;
//输入图像
Mat img;
//灰度值归一化
Mat bgr;
//HSV图像
Mat hsv;
//色相

string windowName = "src";
//输出图像的显示窗口
string dstName = "dst";
//输出图像
Mat dst;
Mat mask;
//回调函数
int main(int argc, char** argv)
{
    //输入图像
    img = imread("G:\\text.jpg");
    if (!img.data || img.channels() != 3)
        return -1;
    dst = Mat::zeros(img.size(), img.type());
    bgr = img.clone();
    //颜色空间转换
    cvtColor(bgr, hsv, CV_BGR2HSV);
    inRange(hsv, Scalar(35, 43, 46), Scalar(77, 255,255), mask);
    //掩模到原图的转换
    for (int r = 0; r < bgr.rows; r++)
    {
        for (int c = 0; c < bgr.cols; c++)
        {
            if (mask.at<uchar>(r, c) == 255)
            {
                dst.at<Vec3b>(r, c) = bgr.at<Vec3b>(r, c);
            }
        }
    }
    //定义输出图像的显示窗口
    namedWindow(dstName, WINDOW_GUI_EXPANDED);
    
    /*Mat gay;
    
    cvtColor(gay, gay, COLOR_RGB2GRAY);*/

    vector<vector<Point> > contours;
    vector<Vec4i> hierarchy;
    findContours(mask, contours, hierarchy, RETR_CCOMP, CHAIN_APPROX_SIMPLE);
    for (int i = 0; i < contours.size(); i++)
    {

        RotatedRect box = minAreaRect(contours[i]);
        Point2f vertex[4];
        box.points(vertex);
        for (int i = 0; i < 4; i++)
            line(img, vertex[i], vertex[(i + 1) % 4], Scalar(100, 200, 211), 2, LINE_AA);
    }
    imshow(windowName, img);
    imshow(dstName, dst);
    waitKey(0);
    return 0;
}