polar_transforms.cpp

An example using the cv::linearPolar and cv::logPolar operations

#include "opencv2/imgproc/imgproc_c.h"
#include "opencv2/videoio/videoio_c.h"
#include "opencv2/highgui/highgui_c.h"

#include <ctype.h>
#include <stdio.h>

static void help( void )
{
 printf("\nThis program illustrates Linear-Polar and Log-Polar image transforms\n"
 "Usage :\n"
 "./polar_transforms [[camera number -- Default 0],[AVI path_filename]]\n\n"
 );
}
int main( int argc, char** argv )
{
 CvCapture* capture = 0;
 IplImage* log_polar_img = 0;
 IplImage* lin_polar_img = 0;
 IplImage* recovered_img = 0;

 help();

 if( argc == 1 || (argc == 2 && strlen(argv[1]) == 1 && isdigit(argv[1][0])))
 capture = cvCaptureFromCAM( argc == 2 ? argv[1][0] - '0' : 0 );
 else if( argc == 2 )
 capture = cvCaptureFromAVI( argv[1] );
 if( !capture )
 {
 fprintf(stderr,"Could not initialize capturing...\n");
 fprintf(stderr,"Usage: %s <CAMERA_NUMBER> , or \n %s <VIDEO_FILE>\n",argv[0],argv[0]);
 help();
 return -1;
 }

 cvNamedWindow( "Linear-Polar", 0 );
 cvNamedWindow( "Log-Polar", 0 );
 cvNamedWindow( "Recovered image", 0 );

 cvMoveWindow( "Linear-Polar", 20,20 );
 cvMoveWindow( "Log-Polar", 700,20 );
 cvMoveWindow( "Recovered image", 20,700 );

 for(;;)
 {
 IplImage* frame = 0;

 frame = cvQueryFrame( capture );
 if( !frame )
 break;

 if( !log_polar_img )
 {
 log_polar_img = cvCreateImage( cvSize(frame->width,frame->height), IPL_DEPTH_8U, frame->nChannels );
 lin_polar_img = cvCreateImage( cvSize(frame->width,frame->height), IPL_DEPTH_8U, frame->nChannels );
 recovered_img = cvCreateImage( cvSize(frame->width,frame->height), IPL_DEPTH_8U, frame->nChannels );
 }

 cvLogPolar(frame,log_polar_img,cvPoint2D32f(frame->width >> 1,frame->height >> 1),70, CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS);
 cvLinearPolar(frame,lin_polar_img,cvPoint2D32f(frame->width >> 1,frame->height >> 1),70, CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS);

#if 0
 cvLogPolar(log_polar_img,recovered_img,cvPoint2D32f(frame->width >> 1,frame->height >> 1),70, CV_WARP_INVERSE_MAP+CV_INTER_LINEAR);
#else
 cvLinearPolar(lin_polar_img,recovered_img,cvPoint2D32f(frame->width >> 1,frame->height >> 1),70, CV_WARP_INVERSE_MAP+CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS);
#endif

 cvShowImage("Log-Polar", log_polar_img );
 cvShowImage("Linear-Polar", lin_polar_img );
 cvShowImage("Recovered image", recovered_img );

 if( cvWaitKey(10) >= 0 )
 break;
 }

 cvReleaseCapture( &capture );
 cvDestroyWindow("Linear-Polar");
 cvDestroyWindow("Log-Polar");
 cvDestroyWindow("Recovered image");

 return 0;
}

#ifdef _EiC
main(1,"laplace.c");
#endif