opencv——对象提取与测量

 #include <opencv2/opencv.hpp>
 #include <iostream>
 #include <math.h>

 using namespace cv;
 using namespace std;

 int main(int argc, char** argv) {
     Mat src = imread("test.jpg");
     if (src.empty()) {
         printf("could not load image...\n");
         return -;
     }
     namedWindow("input image", CV_WINDOW_AUTOSIZE);
     imshow("input image", src);

     //高斯降噪
     Mat blurImage;
     GaussianBlur(src, blurImage, Size(, ), , );
     imshow("blur", blurImage);

     Mat gray_src, binary;
     cvtColor(blurImage, gray_src, COLOR_BGR2GRAY);
     threshold(gray_src, binary, , , THRESH_BINARY | THRESH_TRIANGLE);//颜色单一的图像使用THRESH_TRIANGLE
     imshow("binary", binary);

     // 形态学闭操作，去掉空洞
     Mat morphImage;
     Mat kernel = getStructuringElement(MORPH_RECT, Size(, ), Point(-, -));
     morphologyEx(binary, morphImage, MORPH_CLOSE, kernel, Point(-, -), );
     imshow("morphology", morphImage);

     // 获取最大轮廓
     vector<vector<Point>> contours;
     vector<Vec4i> hireachy;
     findContours(morphImage, contours, hireachy, CV_RETR_EXTERNAL, CHAIN_APPROX_SIMPLE, Point());
     Mat connImage = Mat::zeros(src.size(), CV_8UC3);
     for (size_t t = ; t < contours.size(); t++) {
         Rect rect = boundingRect(contours[t]);
         if (rect.width < src.cols / ) continue;//轮廓筛选
         if (rect.width > (src.cols - )) continue;//轮廓筛选
         double area = contourArea(contours[t]);
         double len = arcLength(contours[t], true);
         drawContours(connImage, contours, static_cast<int>(t), Scalar(, , ), , , hireachy);
         printf("area  of star could : %f\n", area);
         printf("length  of star could : %f\n", len);
     }
     imshow("result", connImage);

     waitKey();
     return ;
 }