contour.cpp

#include <opencv2/opencv.hpp>
#include <opencv2/opencv_lib.hpp>

int
main (int argc, char *argv[])
{
  int i;
  IplImage *src_img = 0;
  IplImage *src_img_gray = 0;
  IplImage *tmp_img;
  CvMemStorage *storage = cvCreateMemStorage (0);
  CvSeq *contours = 0;
  CvPoint *point, *tmp;
  CvSeq *contour;
  CvTreeNodeIterator it;
  FILE *fp;

  src_img = cvLoadImage ("original.jpg", CV_LOAD_IMAGE_COLOR);
  if (src_img == 0)
    exit(-1);
  
  src_img_gray = cvCreateImage (cvGetSize (src_img), IPL_DEPTH_8U, 1);
  cvCvtColor (src_img, src_img_gray, CV_BGR2GRAY);
  tmp_img = cvCreateImage (cvGetSize (src_img), IPL_DEPTH_8U, 1);

  // (1)画像の二値化と輪郭の検出
  cvThreshold (src_img_gray, tmp_img, 120, 255, CV_THRESH_BINARY);
  cvFindContours (tmp_img, storage, &contours, sizeof (CvContour), CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE);

  /* 輪郭シーケンスから座標を取得 */
  if(NULL == (fp=fopen("output.csv", "w"))){
  	printf("Can not open the outfile.\n");
  	return(-1);
  }
  cvInitTreeNodeIterator (&it, contours, 1);

  // (3)各ノード（輪郭）を走査
  while ((contour = (CvSeq *) cvNextTreeNode (&it)) != NULL) {

  // (4)輪郭を構成する頂点座標を取得
    tmp = CV_GET_SEQ_ELEM (CvPoint, contour, 0);
    for (i = 0; i < contour->total; i++) {
      point = CV_GET_SEQ_ELEM (CvPoint, contour, i);
      cvLine (src_img, *tmp, *point, CV_RGB (0, 0, 255), 2);
      if(i != (contour->total)-1){
	      fprintf(fp, "%d, %d, ", point->x, point->y);
      }else{
	      fprintf(fp, "%d, %d", point->x, point->y);
      }
      tmp = point;
    }
  }  
  fclose(fp);

  cvNamedWindow ("Contours", CV_WINDOW_AUTOSIZE);
  cvShowImage ("Contours", src_img);

  cvWaitKey (0);

  cvDestroyWindow ("Contours");
  cvReleaseImage (&src_img);
  cvReleaseImage (&src_img_gray);
  cvReleaseImage (&tmp_img);
  cvReleaseMemStorage (&storage);

  return 0;
}