opencv学习之路（29）、轮廓查找与绘制（八）——轮廓特征属性及应用

一、简介

HSV颜色空间（hue色调，saturation饱和度，value亮度）

二、HSV滑动条

 #include "opencv2/opencv.hpp"
 #include <iostream>
 using namespace cv;
 using namespace std;

 Mat srcImg, hsv_img;
 int h_min =,s_min = ,v_min = ;
 int h_max = ,s_max = ,v_max = ;

 void onChange(int, void* param) {
     Scalar hsv_min(h_min, s_min, v_min);
     Scalar hsv_max(h_max, s_max, v_max);
     Mat dst = Mat::zeros(srcImg.size(), srcImg.type());
     inRange(srcImg, hsv_min, hsv_max, dst);
     imshow("HSV", dst);
 }

 void main()
 {
     srcImg = imread("E://duck2.jpg");
     imshow("src", srcImg);
     cvtColor(srcImg, hsv_img, CV_BGR2HSV); //BGR转到HSV颜色空间
     namedWindow("HSV", CV_WINDOW_AUTOSIZE);
     //创建滚动条
     createTrackbar("h_min", "HSV", &h_min, , onChange, );
     createTrackbar("s_min", "HSV", &s_min, , onChange, );
     createTrackbar("v_min", "HSV", &v_min, , onChange, );
     createTrackbar("h_max", "HSV", &h_max, , onChange, );
     createTrackbar("s_max", "HSV", &s_max, , onChange, );
     createTrackbar("v_max", "HSV", &v_max, , onChange, );
     //回调函数初始化
     onChange(h_min, );
     onChange(s_min, );
     onChange(v_min, );
     onChange(h_max, );
     onChange(s_max, );
     onChange(v_max, );

     waitKey();
 }

三、颜色识别跟踪

putText函数定义为

void putText(Mat& img, const string& text, Point org, int fontFace, double fontScale, Scalar color, intthickness=1, int lineType=8, bool bottomLeftOrigin=false )

参数为

• img – 图像矩阵
• text – string型 文字内容
• org – 文字坐标，以左下角为原点
• fontFace – 字体类型  （包括 FONT_HERSHEY_SIMPLEX, FONT_HERSHEY_PLAIN, FONT_HERSHEY_DUPLEX, FONT_HERSHEY_COMPLEX, FONT_HERSHEY_TRIPLEX, FONT_HERSHEY_COMPLEX_SMALL, FONT_HERSHEY_SCRIPT_SIMPLEX, or FONT_HERSHEY_SCRIPT_COMPLEX,）
• fontScale –字体大小
• color – 字体颜色
• thickness – 字体粗细
• lineType – Line type. See the line for details.
• bottomLeftOrigin – When true, the image data origin is at the bottom-left corner. Otherwise, it is at the top-left corner.

 #include "opencv2/opencv.hpp"
 #include <iostream>
 using namespace cv;
 using namespace std;

 ///green hsv min value
 int h_min = ;
 int s_min = ;
 int v_min = ;
 ///green hsv max value
 int h_max = ;
 int s_max = ;
 int v_max = ;

 void main()
 {
     //识别图片中颜色物体
     Mat srcImg = imread("E://rgb.jpg");
     imshow("src", srcImg);
     Mat dstImg = srcImg.clone();
     Mat hsv_img;  //存储HSV图像
     cvtColor(srcImg,hsv_img,CV_BGR2HSV);

     Scalar hsv_min(h_min,s_min,v_min);
     Scalar hsv_max(h_max, s_max, v_max);
     Mat hsv_green=Mat::zeros(srcImg.size(),CV_8U);
     inRange(hsv_img, hsv_min, hsv_max, hsv_green);
     medianBlur(hsv_green, hsv_green, );//中值滤波
     imshow("hsv_green", hsv_green);

     //找轮廓
     vector<vector<Point>>contours;
     vector<Vec4i>hierarcy;
     //找外层轮廓
     findContours(hsv_green, contours, hierarcy, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_NONE);
     vector<Rect>boundRect(contours.size());
     //遍历每个轮廓
     for (int i = ; i < contours.size(); i++)
     {
         boundRect[i] = boundingRect(Mat(contours[i]));//计算外接矩形
         //top、left、right、bottom    tl左上    br右下
         rectangle(dstImg,boundRect[i].tl(), boundRect[i].br(),Scalar(,,),,);
         //Point org = boundRect[i].tl();
         Point org = boundRect[i].br();
         putText(dstImg,"green",org,CV_FONT_HERSHEY_SIMPLEX,1.2f,CV_RGB(,,),,);
     }
     imshow("result", dstImg);

     waitKey();
 }

视频颜色跟踪

 #include "opencv2/opencv.hpp"
 using namespace cv;

 //设置HSV颜色区间
 int blue_min_h = ;
 int blue_min_s = ;
 int blue_min_v = ;
 int blue_max_h = ;
 int blue_max_s = ;
 int blue_max_v = ;

 int green_min_h = ;
 int green_min_s = ;
 int green_min_v = ;
 int green_max_h = ;
 int green_max_s = ;
 int green_max_v = ;

 int red_min_h = ;
 int red_min_s = ;
 int red_min_v = ;
 int red_max_h = ;
 int red_max_s = ;
 int red_max_v = ;

 void main()
 {
     VideoCapture cap;
     cap.open("E://1.mp4");
     if (!cap.isOpened())//如果视频不能正常打开则返回
         return;
     Mat src,dst,hsv,ROI;

     while ()
     {
         cap >> src;
         if (src.empty())//如果某帧为空则退出循环
             break;
         //imshow("video", src);
         dst = src.clone();
         ROI=src(Rect(,,,));//x,y,w,h    xy坐标，宽度，高度        区分蓝色按钮和右边的蓝色区域
         GaussianBlur(ROI,ROI,Size(,),);
         cvtColor(ROI, hsv, CV_BGR2HSV);
         Scalar blue_min(blue_min_h, blue_min_s, blue_min_v);
         Scalar blue_max(blue_max_h, blue_max_s, blue_max_v);
         Scalar green_min(green_min_h, green_min_s, green_min_v);
         Scalar green_max(green_max_h, green_max_s, green_max_v);
         Scalar red_min(red_min_h, red_min_s, red_min_v);
         Scalar red_max(red_max_h, red_max_s, red_max_v);
         Mat hsv_blue = Mat::zeros(src.size(), CV_8U);
         Mat hsv_green = Mat::zeros(src.size(), CV_8U);
         Mat hsv_red = Mat::zeros(src.size(), CV_8U);
         inRange(hsv, blue_min, blue_max, hsv_blue);//颜色区间范围筛选
         inRange(hsv, green_min, green_max, hsv_green);
         inRange(hsv, red_min, red_max, hsv_red);
         medianBlur(hsv_blue, hsv_blue, );//中值滤波
         medianBlur(hsv_green, hsv_green, );
         medianBlur(hsv_red, hsv_red, );

         //找轮廓
         vector<vector<Point>>contours_blue,contours_green,contours_red;
         vector<Vec4i>hierarchy_blue,hierarchy_green,hierarchy_red;
         //蓝色轮廓
         findContours(hsv_blue, contours_blue, hierarchy_blue, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_NONE);
         vector<Rect>boundRect_blue(contours_blue.size());//定义外接矩形集合
         for (int i = ; i < contours_blue.size(); i++)
         {
             boundRect_blue[i] = boundingRect(Mat(contours_blue[i]));//计算外接矩形
             rectangle(dst, boundRect_blue[i].tl(), boundRect_blue[i].br(), Scalar(, , ), , );
             Point org = boundRect_blue[i].br();
             putText(dst, "blue", org, CV_FONT_HERSHEY_SIMPLEX, 1.2f, CV_RGB(,,), , );
         }
         //绿色轮廓
         findContours(hsv_green, contours_green, hierarchy_green, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_NONE);
         vector<Rect>boundRect_green(contours_green.size());//定义外接矩形集合
         for (int i = ; i < contours_green.size(); i++)
         {
             boundRect_green[i] = boundingRect(Mat(contours_green[i]));//计算外接矩形
             rectangle(dst, boundRect_green[i].tl(), boundRect_green[i].br(), Scalar(, , ), , );
             Point org = boundRect_green[i].br();
             putText(dst, "green", org, CV_FONT_HERSHEY_SIMPLEX, 1.2f, CV_RGB(, , ), , );
         }
         //红色轮廓
         findContours(hsv_red, contours_red, hierarchy_red, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_NONE);
         vector<Rect>boundRect_red(contours_red.size());//定义外接矩形集合
         for (int i = ; i < contours_red.size(); i++)
         {
             boundRect_red[i] = boundingRect(Mat(contours_red[i]));//计算外接矩形
             rectangle(dst, boundRect_red[i].tl(), boundRect_red[i].br(), Scalar(, , ), , );
             Point org = boundRect_red[i].br();
             putText(dst, "red", org, CV_FONT_HERSHEY_SIMPLEX, 1.2f, CV_RGB(,,), , );
         }

         imshow("result", dst);
         waitKey();//每帧延时20毫秒
     }
     cap.release();//释放资源
 }