#include <stdio.h>

#ifdef _CH_
#pragma package <opencv>
#endif

#ifndef _EiC
#include "cv.h"
#include "highgui.h"
#include <math.h>
#endif

int sizeX, sizeY;
int levels = 1;
CvSeq* contours = 0;
IplImage* output = 0;

void on_change(int pos)
{
  // config
  IplImage* img2 = cvCreateImage( cvSize(sizeX, sizeY), 8, 3 );
  CvSeq* _contours = contours;
  int _levels = levels;
  // draw image
  printf("\tcontour level %i \t[ok]\n", pos);
  cvZero(img2);
  cvDrawContours(img2, _contours, CV_RGB(255,0,0), CV_RGB(0,255,0), _levels, 1, CV_AA, cvPoint(0,0) );
  cvShowImage("img_contour", img2);
  output = cvCloneImage(img2);
  cvReleaseImage(&img2);
}


int main(int argc, char** argv)
{
  int i, j;
  CvMemStorage* memStorage = cvCreateMemStorage(0);

  // open image
  IplImage* img = 0;
  char* filename = argc == 2 ? argv[1] : (char*)"contours-sample.bmp";
  if( (img = cvLoadImage(filename,0)) == 0 )
  {
    printf("open image \t\t\t[failed]\n");
    exit(0);
  }
  else
  {
    printf("open image \t\t\t[ok]\n");
  }

  sizeX = img->width;
  sizeY = img->height;

  // show orginal image
  printf("show orginal \t\t\t[ok]\n");
  cvNamedWindow("img_base", 1);
  cvShowImage("img_base", img);
  cvWaitKey(0);

  // find contours
  printf("find contours \t\t\t[ok]\n");
  cvFindContours(img, memStorage, &contours, sizeof(CvContour),
      CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0) );

  // show contours image
  cvNamedWindow("img_contour", 1);
  cvCreateTrackbar("levels", "img_contour", &levels, 15, on_change);
  on_change(levels);
  cvWaitKey(0);
  cvDestroyWindow("img_base");
  cvDestroyWindow("img_contour");

  // save image
  printf("save image \t\t\t[ok]\n");
  cvSaveImage("contours-output.bmp", output);
  cvWaitKey(0);

  // ending program
  printf("exit program \t\t\t[ok]\n");
  cvReleaseMemStorage(&memStorage);
  cvReleaseImage(&img);
  return 0;
}

#ifdef _EiC
main(1,"");
#endif