c++ - findContours在opencv中找不到轮廓

Question

我一直在尝试从相机加载图像，但遇到错误。我认为 findContours 函数有问题。这是代码:

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

using namespace cv;
using namespace std;

Mat src; Mat src_gray;
int max_thresh = 255;
RNG rng(12345);

/// Function header
void thresh_callback(int, void* );

/** @function main */
int main( int argc, char** argv )
{
  /// Load source image and convert it to gray
  VideoCapture cap(1);
  cap>>src;

  /// Convert image to gray and blur it
  cvtColor( src, src_gray, CV_BGR2GRAY );
  blur( src_gray, src_gray, Size(3,3) );

  /// Create Window
  char* source_window = "Source";
  namedWindow( source_window, CV_WINDOW_AUTOSIZE );
  imshow( source_window, src );

  thresh_callback( 0, 0 );

  waitKey(0);
  return(0);
}

/** @function thresh_callback */
void thresh_callback(int, void* )
{
  Mat canny_output;
  vector<vector<Point> > contours;
  vector<Vec4i> hierarchy;

  /// Detect edges using canny
  Canny( src_gray, canny_output, 100, 100*2, 3 );
  /// Find contours
  findContours( canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );

  /// Draw contours
  Mat drawing = Mat::zeros( canny_output.size(), CV_8UC3 );
  for( int i = 0; i< contours.size(); i++ )
     {
       Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
       drawContours( drawing, contours, i, color, 2, 8, hierarchy, 0, Point() );
     }

  /// Show in a window
  namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
  imshow( "Contours", drawing );
}

这里是错误:

• Critical error detected c0000374 ConsoleApplication8.exe has triggered a breakpoint.

如有任何帮助，我将不胜感激。

Answer 1

我在使用该功能时遇到了同样的问题(或至少是类似的问题)。我无法修复它，所以我改用旧的 C 风格的 cvFindContours 函数。我在其中包含了一个示例函数，我使用 cvFindContours 函数来清理 blob 图像。这可能不是最快的解决方案，但至少可行。

void filtBproject(Mat& Bproject){

    Scalar          color       = CV_RGB(255,255,255); // text color
    IplImage*       BprojectIpl =  &IplImage(Bproject);
    CvMemStorage*   storage     = cvCreateMemStorage(0);
    CvSeq*          contours    = 0;
    int             numCont     = 0;
    int             contAthresh = 45;

    numCont= cvFindContours( BprojectIpl, storage, &contours, sizeof(CvContour),
                    CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0) );

    cvSet(BprojectIpl, cvScalar(0,0,0));
    for( ; contours != 0; contours = contours->h_next )
        {

            if ( (cvContourArea(contours, CV_WHOLE_SEQ) > contAthresh) ){
                cvDrawContours( BprojectIpl, contours, color, color, -1, CV_FILLED, 8 );
            }
        }
}