96 lines
2.7 KiB
C++
96 lines
2.7 KiB
C++
/**
|
|
* @function moments_demo.cpp
|
|
* @brief Demo code to calculate moments
|
|
* @author OpenCV team
|
|
*/
|
|
|
|
#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 = 100;
|
|
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
|
|
src = imread( argv[1], 1 );
|
|
|
|
/// 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 );
|
|
|
|
createTrackbar( " Canny thresh:", "Source", &thresh, max_thresh, thresh_callback );
|
|
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, thresh, thresh*2, 3 );
|
|
/// Find contours
|
|
findContours( canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
|
|
|
|
/// Get the moments
|
|
vector<Moments> mu(contours.size() );
|
|
for( int i = 0; i < contours.size(); i++ )
|
|
{ mu[i] = moments( contours[i], false ); }
|
|
|
|
/// Get the mass centers:
|
|
vector<Point2f> mc( contours.size() );
|
|
for( int i = 0; i < contours.size(); i++ )
|
|
{ mc[i] = Point2f( mu[i].m10/mu[i].m00 , mu[i].m01/mu[i].m00 ); }
|
|
|
|
/// 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() );
|
|
circle( drawing, mc[i], 4, color, -1, 8, 0 );
|
|
}
|
|
|
|
/// Show in a window
|
|
namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
|
|
imshow( "Contours", drawing );
|
|
|
|
/// Calculate the area with the moments 00 and compare with the result of the OpenCV function
|
|
printf("\t Info: Area and Contour Length \n");
|
|
for( int i = 0; i< contours.size(); i++ )
|
|
{
|
|
printf(" * Contour[%d] - Area (M_00) = %.2f - Area OpenCV: %.2f - Length: %.2f \n", i, mu[i].m00, contourArea(contours[i]), arcLength( contours[i], true ) );
|
|
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() );
|
|
circle( drawing, mc[i], 4, color, -1, 8, 0 );
|
|
}
|
|
}
|
|
|