main.cpp

#include <opencv2/imgcodecs.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <iostream>

using namespace cv;
using namespace std;

int hmin = 105, smin = 45, vmin = 45;
int hmax = 125, smax = 255, vmax = 255;

int main()
{
    Mat a,img,mask;
    while(true){
        a=imread("/home/chenwanyi/图片/6.jpeg");
        resize(a,a,Size(500,500));
        cvtColor(a,img,COLOR_BGR2HSV);
        //筛选蓝色，使其变白
        Scalar lower(hmin, smin, vmin);
        Scalar upper(hmax, smax, vmax);
        inRange(img, lower, upper, mask);
        //获得轮廓
        vector<vector<Point>> contours; //轮廓数据
        vector<Vec4i> hierarchy;
        findContours(mask,contours,hierarchy,CV_RETR_LIST,CV_CHAIN_APPROX_NONE,Point());
        drawContours(a,contours,-1,Scalar(0,255,0),5);
        //获取行列
        int img_width = a.cols;
        int img_height = a.rows;
        //拟合方法采用最小二乘法
        Vec4f fitline;
        fitLine(contours[0],fitline,CV_DIST_L2,0,0.01,0.01);
        //求出直线上的两个点
        double k_line = fitline[1]/fitline[0];
        Point p1(0,k_line*(0 - fitline[2]) + fitline[3]);
        Point p2(img_width - 1,k_line*(img_width - 1 - fitline[2]) + fitline[3]);
        //显示拟合出的直线方程
        char text_equation[1024];
        sprintf(text_equation,"y-%.2f=%.2f(x-%.2f)",fitline[3],k_line,fitline[2]);
        putText(a,text_equation,Point(30,50),CV_FONT_HERSHEY_COMPLEX,0.5,Scalar(0,0,255),1,8);
        //显示拟合出的直线
        line(a,p1,p2,Scalar(0,0,255),2);
        //轮条滚动选择范围
        namedWindow("Trackbars", (640, 200));
        createTrackbar("Hue Min", "Trackbars", &hmin, 179);
        createTrackbar("Hue Max", "Trackbars", &hmax, 179);
        createTrackbar("Sat Min", "Trackbars", &smin, 255);
        createTrackbar("Sat Max", "Trackbars", &smax, 255);
        createTrackbar("Val Min", "Trackbars", &vmin, 255);
        createTrackbar("Val Max", "Trackbars", &vmax, 255);
        //显示图像
        imshow("1",a);
        waitKey(1);
        //根据斜率返回方向
        cout<<k_line<<endl;
        if(k_line<1&&k_line>0){return 1;}
        else if(k_line>-1||k_line<0){return 2;}
        else if(k_line>2||k_line<-2){return 3;}
        // 1=左/ 2 = 右 / 3=直行
    }
}