houghline.c

利用OPenCV写的一个hough变换检测直线的程序

/* This is a standalone program. Pass an image name as a first parameter of the program.   Switch between standard and probabilistic Hough transform by changing "#if 1" to "#if 0" and back */
#include <cv.h>
#include <highgui.h>
#include <math.h> 
int main(int argc, char** argv)
{    const char* filename = argc >= 2 ? argv[1] : "pic1.png";    
     IplImage* src = cvLoadImage( filename, 0 );    
     IplImage* dst;    
     IplImage* color_dst;    
     CvMemStorage* storage = cvCreateMemStorage(0);    
     CvSeq* lines = 0;    
     int i;     

     if( !src )        
          return -1;     
     dst = cvCreateImage( cvGetSize(src), 8, 1 );    
     color_dst = cvCreateImage( cvGetSize(src), 8, 3 );     

     cvCanny( src, dst, 50, 200, 3 );    
     cvCvtColor( dst, color_dst, CV_GRAY2BGR );
#if 0    
     lines = cvHoughLines2( dst, storage, CV_HOUGH_STANDARD, 1, CV_PI/180, 100, 0, 0 );     

     for( i = 0; i < MIN(lines->total,100); i++ )    
    {        
       float* line = (float*)cvGetSeqElem(lines,i);        
       float rho = line[0];        
       float theta = line[1];        
       CvPoint pt1, pt2;        
      double a = cos(theta), b = sin(theta);        
      double x0 = a*rho, y0 = b*rho;        
      pt1.x = cvRound(x0 + 1000*(-b));        
      pt1.y = cvRound(y0 + 1000*(a));        
      pt2.x = cvRound(x0 - 1000*(-b));        
      pt2.y = cvRound(y0 - 1000*(a));        
      cvLine( color_dst, pt1, pt2, CV_RGB(255,0,0), 3, CV_AA, 0 );    
}
    
     lines = cvHoughLines2( dst, storage, CV_HOUGH_PROBABILISTIC, 1, CV_PI/180, 50, 50, 10 );    
    for( i = 0; i < lines->total; i++ )   
    {       
      CvPoint* line = (CvPoint*)cvGetSeqElem(lines,i);        
      cvLine( color_dst, line[0], line[1], CV_RGB(255,0,0), 3, CV_AA, 0 );   
    }    
    cvNamedWindow( "Source", 1 );    
    cvShowImage( "Source", src );     
    cvNamedWindow( "Hough", 1 );    
    cvShowImage( "Hough", color_dst );     
    cvWaitKey(0);     
    return 0;
}