步骤如下:
1.图片灰化;
2.中值滤波 去噪
3.求图片的光影(自动光学检测)
4.除法去光影
5.阈值操作
6.实现了三种目标检测方法
主要分两种连通区域和findContours
过程遇到了错误主要是图片忘了灰化处理,随机颜色的问题。下面代码都已经进行了解决
这是findContours的效果
下面是连通区域的结果
#include <opencv2\core\utility.hpp> #include <opencv2\imgproc.hpp> #include <opencv2\highgui.hpp> #include<opencv2\opencv.hpp> #include <opencv2\core\core.hpp> #include <opencv2\core\matx.hpp> #include<string> #include <iostream> #include <limits> using namespace std; using namespace cv; Mat img = imread("C:\\Users\\hasee\\Desktop\\luosi.jpg",0); Mat removeLight(Mat imge, Mat pattern, int method); Mat calculateLightPattern(Mat img); static Scalar randomColor(RNG& rng); void ConnectedComponents(Mat img); void ConnectedComponetsStats(Mat img); void FindContoursBasic(Mat img); void main() { Mat img_noise; medianBlur(img,img_noise,3); Mat pattern = calculateLightPattern(img_noise); Mat re_light = removeLight(img_noise, pattern, 1); Mat img_thr; threshold(re_light,img_thr,30,255,THRESH_BINARY); //ConnectedComponents(img_thr); ConnectedComponetsStats(img_thr); //FindContoursBasic(img_thr); waitKey(0); } Mat removeLight(Mat imge, Mat pattern, int method) { Mat aux; if (method == 1) { Mat img32, pattern32; imge.convertTo(img32, CV_32F); pattern.convertTo(pattern32, CV_32F); aux = 1 - (img32 / pattern32); aux = aux * 255; aux.convertTo(aux, CV_8U); } else { aux = pattern - imge; } return aux; } Mat calculateLightPattern(Mat img) { Mat pattern; blur(img, pattern, Size(img.cols / 3, img.cols / 3)); return pattern; } static Scalar randomColor(RNG& rng) { int icolor = (unsigned)rng; return Scalar(icolor & 255, (icolor 8) & 255, (icolor 16) & 255); } void ConnectedComponents(Mat img) { Mat lables; int num_objects = connectedComponents(img, lables); if (num_objects < 2) { cout << "未检测到目标" << endl; return; } else { cout << "检测到的目标数量: " << num_objects - 1 << endl; } Mat output = Mat::zeros(img.rows,img.cols,CV_8UC3); RNG rng(0xFFFFFFFF); for (int i = 1; i < num_objects;i++) { Mat mask = lables == i; output.setTo(randomColor(rng),mask); } imshow("Result",output); } void ConnectedComponetsStats(Mat img) { Mat labels, stats, centroids; int num_objects = connectedComponentsWithStats(img,labels,stats,centroids); if (num_objects<2) { cout << "未检测到目标" << endl; return; } else { cout << "检测到的目标数量: " << num_objects - 1 << endl; } Mat output = Mat::zeros(img.rows, img.cols, CV_8UC3); RNG rng(0xFFFFFFFF); for (int i = 1; i < num_objects; i++) { Mat mask = labels == i; output.setTo(randomColor(rng), mask); stringstream ss; ss << "area: " << stats.at<int>(i,CC_STAT_AREA); putText(output,ss.str(), centroids.at<Point2d>(i),FONT_HERSHEY_SIMPLEX,0.4,Scalar(255,255,255)); } imshow("Result", output); } void FindContoursBasic(Mat img) { vector<vector<Point contours; findContours(img, contours, RETR_EXTERNAL, CHAIN_APPROX_SIMPLE); Mat output = Mat::zeros(img.rows, img.cols, CV_8UC3); if (contours.size()==0) { cout << "未检测到对象" << endl; return; }else{ cout << "检测到对象数量: " << contours.size() << endl; } RNG rng(0xFFFFFFFF); for (int i = 0; i < contours.size(); i++) drawContours(output,contours,i,randomColor(rng)); imshow("Result", output); }
补充知识:SURF特征点检测与匹配之误匹配点删除
SURF特征点检测与匹配之误匹配点删除
SURF(SpeededUp Robust Feature)是加速版的具有鲁棒性的算法,是SIFT算法的加速版。
但是SURF特征匹配之后有大量的误匹配点,需要对这些误匹配点进行删除。
这里不从理论上讲解SURF原理等,直接说用法。
特征匹配的步骤分为三步:
1、找出特征点
2、描述特征点
3、特征点匹配
具体基本代码见最后。具体的可以看毛星云的书籍,但是个人认为其编程风格不严谨,自己有做改动。
但是匹配出来的结果如下:
有很多的误匹配点,如何对误匹配点进行删除呢。
双向匹配加距离约束。
实验结果如下:效果还是非常好的。
#include "stdafx.h" #include <opencv2\opencv.hpp> #include <opencv2\nonfree\nonfree.hpp> #include <opencv2\legacy\legacy.hpp> #include <iostream> int _tmain(int argc, _TCHAR* argv[]) { //读取图片 cv::Mat srcImg1 = cv::imread("1.jpg", 1); cv::Mat srcImg2 = cv::imread("2.jpg", 1); if (srcImg1.empty() || srcImg2.empty()) { std::cout << "Read Image ERROR!" << std::endl; return 0; } //SURF算子特征点检测 int minHessian = 700; cv::SurfFeatureDetector detector(minHessian);//定义特征点类对象 std::vector<cv::KeyPoint> keyPoint1, keyPoint2;//存放动态数组,也就是特征点 detector.detect(srcImg1, keyPoint1); detector.detect(srcImg2, keyPoint2); //特征向量 cv::SurfDescriptorExtractor extrator;//定义描述类对象 cv::Mat descriptor1, descriptor2;//描述对象 extrator.compute(srcImg1, keyPoint1, descriptor1); extrator.compute(srcImg2, keyPoint2, descriptor2); //BruteForce暴力匹配 cv::BruteForceMatcher <cv::L2<floatmatcher;//匹配器 std::vector <cv::DMatch> matches; matcher12.match(descriptor1, descriptor2, matches); //绘制关键点 cv::Mat imgMatch; cv::drawMatches(srcImg1, keyPoint1, srcImg2, keyPoint2, matches, imgMatch); cv::namedWindow("匹配图", CV_WINDOW_AUTOSIZE); cv::imshow("匹配图", imgMatch); cv::imwrite("匹配图.jpg", imgMatch); cv::waitKey(10); return 0; }
以上这篇浅谈opencv自动光学检测、目标分割和检测(连通区域和findContours)就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。