opencv c ++查找轮廓的内切圆

本文介绍了opencv c ++查找轮廓的内切圆的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想找到轮廓的最大内切圆.

我用cv::findContours检测到轮廓，并以vector<Point>的形式存在.

I have detected the contour with cv::findContours and it is there as a vector<Point>.

我知道如何检测最小封闭圆(cv::minEnclosingCircle)，但不知道如何获取最大封闭圆.该怎么做?

I know how to detect the minimum enclosing circle (cv::minEnclosingCircle), but not how to get the maximum inclosing circle. How to do this?

问题2:如何使刻划和外接圆以质心为中心?

Question2: How do i get the inscribing and circumscribing circles centered on the center of mass?

为澄清起见，我尝试描述这些圆圈的含义:

For clarification, i try to describe, what i mean with these circels:

最小包围圈:从外部触摸物体，中心位置无所谓，最小面积.

外接圆:从外部触摸对象，中心位置位于对象的质心上，最小面积.

最大闭合圆:从内部触摸物体，中心位置无所谓，最大面积.

内切圆:从内部触摸对象，对象的质心的中心位置，最大面积.

min enclosing circle: touching object from outside, center position doesn't matter, minimum area.

circumscribing circle: touching object from outside, center position on the center of mass of the object, minimum area.

max inclosing circle: touching object from inside, center position doesn't matter, maximum area.

inscribing circle: touching object from inside, center position on the center of mass of the object, maximum area.

推荐答案

您可以:

1)从轮廓创建蒙版

2)计算蒙版上的distanceTransform

3)最大值是半径，位置是中心

3) The highest value is the radius, its position is the center

代码:

#include <opencv2\opencv.hpp> int main() { // Load image cv::Mat1b img = cv::imread("path_to_img", cv::IMREAD_GRAYSCALE); // Correct image cv::Mat1b bin = img < 127; // Find contour std::vector<std::vector<cv::Point>> contours; cv::findContours(bin, contours, cv::RETR_EXTERNAL, cv::CHAIN_APPROX_SIMPLE); // Draw on mask cv::Mat1b mask(bin.rows, bin.cols, uchar(0)); cv::drawContours(mask, contours, 0, cv::Scalar(255), cv::FILLED); // Distance Trasnsform cv::Mat1f dt; cv::distanceTransform(mask, dt, cv::DIST_L2, 5, cv::DIST_LABEL_PIXEL); // Find max value double max_val; cv::Point max_loc; cv::minMaxLoc(dt, nullptr, &max_val, nullptr, &max_loc); // Output image cv::Mat3b out; cv::cvtColor(img, out, cv::COLOR_GRAY2BGR); cv::circle(out, max_loc, max_val, cv::Scalar(0, 255, 0)); return 0; }