[c++] OpenCV 직선검출

소스코드

//영상에서 cvHoughLines2 함수로 직선검출

#include "cv.h"
#include "highgui.h"

int main()
{
 IplImage *srcImage;
 if((srcImage = cvLoadImage("square3.jpg",CV_LOAD_IMAGE_GRAYSCALE)) ==NULL)
  return -1;
 IplImage *edgeImage = cvCreateImage(cvGetSize(srcImage),IPL_DEPTH_8U,1);
 IplImage* dstImage = cvCreateImage(cvGetSize(srcImage),IPL_DEPTH_8U,3);
 
 CvMemStorage* storage = cvCreateMemStorage(0);
 CvSeq* seqLines;
 int k;

 cvCanny(srcImage,edgeImage,50,100,3);
 seqLines = cvHoughLines2(edgeImage,storage,CV_HOUGH_STANDARD,1,CV_PI/180,100,0,0);
 //cvHoughLines2(영상,검출된 직선의 메모리 공간 - 행렬형태저장,method,원점으로부터의 거리의 간격, x축과의 각도=라디안간격, 직선을 검출하기 위한 임계값, param1=0.param2=0)
 /*
 method - CV_HOUGH_STANDARD : 직선검출
   - CV_HOUGH_PROBABILISTIC : 양끝점이 있는 선분을 검출
   - CV_HOUGH_MULTI_SCALE : STANDARD와 같음

 */
 //seqLines = cvHoughLines2(edgeImage,storage,CV_HOUGH_MULTI_SCALE,4,CV_PI/180,100,4,2);
 printf("seqLines->total = %d\n",seqLines->total);
 cvCvtColor(srcImage,dstImage,CV_GRAY2BGR);

 for(k=0;k<seqLines->total;k++)
 {
  float* line;
  float rho, theta; //원점에서 (rho,theta)에 의한 직선과 수직으로 만나는 좌표 점(x0,y0)을 x0=rho*c, y0=rho*s로 계산
  float c,s;
  float x0,y0;

  line = (float*)cvGetSeqElem(seqLines,k);

  rho = line[0];
  theta = line[1];

  printf("line[%4d]=(rho,theta)=(%f,%f)\n",k,rho,theta);

  //drawing line
  c = cos(theta);
  s = sin(theta);
  x0 = rho*c;
  y0 = rho*s;

  CvPoint pt1, pt2;
  pt1.x = cvRound(x0 + 1000*(-s));
  pt1.y = cvRound(y0 + 1000*(c));

  pt2.x = cvRound(x0 - 1000*(-s));
  pt2.y = cvRound(y0 - 1000*(c));

  cvLine(dstImage,pt1,pt2,CV_RGB(255,0,0),2,8);
 }
 /*
 //to detect line segments

 seqLines = cvHoughLines2(edgeImage,storage,CV_HOUGH_PROBABILISTIC,1,CV_PI/180,100,10,10);
 printf("seqLines -> total = %d\n",seqLines->total);

 cvCvtColor(srcImage,dstImage,CV_GRAY2BGR);

 for(k=0;k<seqLines->total;k++)
 {
  CvPoint* lineSeg = (CvPoint*)cvGetSeqElem(seqLines,k);
  printf("P1(%4d,%4d) - P2(%4d,%4d)\n",lineSeg[0].x, lineSeg[0].y, lineSeg[1].x, lineSeg[1].y);
  cvLine(dstImage,lineSeg[0], lineSeg[1], CV_RGB(255,0,0), 1, 8);
 }

 */

 cvNamedWindow("dstImage",CV_WINDOW_AUTOSIZE);
 cvShowImage("dstImage",dstImage);
 cvWaitKey(0);
 cvDestroyAllWindows();
 cvReleaseImage(&srcImage);
 cvReleaseImage(&dstImage);
 cvReleaseMemStorage(&storage);
 cvReleaseImage(&edgeImage);
 return 0;
}

 

 

 

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