Question

我使用下面的代码来检测手并在其中绘制一个凸包。

以下是我的代码流程：

1）角点检测（阈值）。

2）腐蚀+膨胀。

3）轮廓检测。

4）最大轮廓的凸包。

5）凸性。

6）Countour + Hull绘制轮廓。

#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 thresh = 147;
 int max_thresh = 255;
 RNG rng(12345);

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

/** @function main */
int main( int argc, char** argv )
 {

//   src = imread( "D:\\Projects\\Proposals\\Knuckle_Detection\\images\\picture028.jpg", 1 );

  VideoCapture cap(0); 

  while(1)
  {
      cap>>src;
   /// Convert image to gray and blur it
   resize(src,src,Size(640,480),0,0,INTER_LINEAR);
   cvtColor( src, src_gray, CV_BGR2GRAY );
   blur( src_gray, src_gray, Size(3,3) );

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

   thresh_callback( 0, 0 );

   waitKey(5);
  }
   return(0);
 }

 /** @function thresh_callback */
 void thresh_callback(int, void* )
 {
   Mat src_copy = src.clone();
   Mat threshold_output;
   vector<vector<Point> > contours;
   vector<Vec4i> hierarchy;

   /// Detect edges using Threshold
   threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY||CV_THRESH_OTSU );

   imshow("b/f threshold", threshold_output);

   erode(threshold_output,threshold_output,Mat ());
   dilate(threshold_output,threshold_output,Mat ());

   imshow("Threshold",threshold_output);


findContours( threshold_output, contours, hierarchy, CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE, Point(0, 0));

   /// Find the convex hull object for each contour
   vector<vector<Point > >hull( contours.size() );
   vector<vector<Vec4i> >defects( contours.size() );
   vector<vector<int > >hull1( contours.size() );

   for( int i = 0; i < contours.size(); i++ )
        {  
         convexHull( Mat(contours[i]), hull[i], false ); 
         convexHull( Mat(contours[i]), hull1[i], false ); 

        }

      for( int i = 0; i < contours.size(); i++ )
        {  
         //convexHull( Mat(contours[i]), hull[i], false ); 
         if (contours[i].size() >3 )
           {

            convexityDefects(contours[i], hull1[i], defects[i]);
            cout<<"inside"<<endl;
           }
        }

   /// Draw contours + hull results
   Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
   for( int i = 0; i< contours.size(); i++ )
      {

       Scalar color = Scalar( rng.uniform(10, 10), rng.uniform(0,255), rng.uniform(0,10) );
               drawContours( src, contours, i, color, 5, 8, vector<Vec4i>(), 0, Point() );
              drawContours( src, hull, i, color, 5, 8, vector<Vec4i>(), 0, Point() );
       cout<<"in"<<endl;

       cout<<"out"<<endl;
      }

   /// Show in a window
   namedWindow( "Result", CV_WINDOW_AUTOSIZE );
   imshow( "Result", src );
 }

以下是代码的输出。

enter image description here