OpenCV 未检测到图片中的圆圈

Question

我有问题。我有代码：

#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>

using namespace cv;
using namespace std;

/** @function main */
int main(int argc, char** argv)
{
  Mat src, src_gray;

  /// Read the image
  src = imread( argv[1], 1 );

  if( !src.data )
    { return -1; }

  /// Convert it to gray
  cvtColor( src, src_gray, CV_BGR2GRAY );

  /// Reduce the noise so we avoid false circle detection
  GaussianBlur( src_gray, src_gray, Size(9, 9), 2, 2 );

  vector<Vec3f> circles;

  /// Apply the Hough Transform to find the circles
  HoughCircles( src_gray, circles, CV_HOUGH_GRADIENT, 1, src_gray.rows/8, 200, 100, 0, 0 );

  /// Draw the circles detected
  for( size_t i = 0; i < circles.size(); i++ )
  {
      Point center(cvRound(circles[i][0]), cvRound(circles[i][1]));
      int radius = cvRound(circles[i][2]);
      // circle center
      circle( src, center, 3, Scalar(0,255,0), -1, 8, 0 );
      // circle outline
      circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 );
   }

  /// Show your results
  namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE );
  imshow( "Hough Circle Transform Demo", src );

  waitKey(0);
  return 0;
}

这是 OpenCV 网站上的示例 (http://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/hough_circle/hough_circle.html)

我有以下图片：

Image

对于上面的图像，代码 OpenCV 没有检测到圆 - circles.size() 等于 0。

我该怎么办？修改代码什么？

Answer 1

您使用的是默认阈值（200 和 100）与圆（太阳火焰）有明显偏差的图像。不是编程错误，只是 data/settings 问题。

OpenCV 未检测到图片中的圆圈

OpenCV not detect a circle in the picture

c++

image

opencv

geometry

detection