converted Kalman sample to C++

This commit is contained in:
Vadim Pisarevsky 2010-12-03 17:46:36 +00:00
parent 103bbaf09c
commit fe72a6eeb3
2 changed files with 101 additions and 111 deletions

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#include "opencv2/video/tracking.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <stdio.h>
void help()
{
printf( "\nExamle of c calls to OpenCV's Kalman filter.\n"
" Tracking of rotating point.\n"
" Rotation speed is constant.\n"
" Both state and measurements vectors are 1D (a point angle),\n"
" Measurement is the real point angle + gaussian noise.\n"
" The real and the estimated points are connected with yellow line segment,\n"
" the real and the measured points are connected with red line segment.\n"
" (if Kalman filter works correctly,\n"
" the yellow segment should be shorter than the red one).\n"
"\n"
" Pressing any key (except ESC) will reset the tracking with a different speed.\n"
" Pressing ESC will stop the program.\n"
);
}
int main(int argc, char** argv)
{
const float A[] = { 1, 1, 0, 1 };
help();
IplImage* img = cvCreateImage( cvSize(500,500), 8, 3 );
CvKalman* kalman = cvCreateKalman( 2, 1, 0 );
CvMat* state = cvCreateMat( 2, 1, CV_32FC1 ); /* (phi, delta_phi) */
CvMat* process_noise = cvCreateMat( 2, 1, CV_32FC1 );
CvMat* measurement = cvCreateMat( 1, 1, CV_32FC1 );
CvRNG rng = cvRNG(-1);
char code = -1;
cvZero( measurement );
cvNamedWindow( "Kalman", 1 );
for(;;)
{
cvRandArr( &rng, state, CV_RAND_NORMAL, cvRealScalar(0), cvRealScalar(0.1) );
memcpy( kalman->transition_matrix->data.fl, A, sizeof(A));
cvSetIdentity( kalman->measurement_matrix, cvRealScalar(1) );
cvSetIdentity( kalman->process_noise_cov, cvRealScalar(1e-5) );
cvSetIdentity( kalman->measurement_noise_cov, cvRealScalar(1e-1) );
cvSetIdentity( kalman->error_cov_post, cvRealScalar(1));
cvRandArr( &rng, kalman->state_post, CV_RAND_NORMAL, cvRealScalar(0), cvRealScalar(0.1) );
for(;;)
{
#define calc_point(angle) \
cvPoint( cvRound(img->width/2 + img->width/3*cos(angle)), \
cvRound(img->height/2 - img->width/3*sin(angle)))
float state_angle = state->data.fl[0];
CvPoint state_pt = calc_point(state_angle);
const CvMat* prediction = cvKalmanPredict( kalman, 0 );
float predict_angle = prediction->data.fl[0];
CvPoint predict_pt = calc_point(predict_angle);
float measurement_angle;
CvPoint measurement_pt;
cvRandArr( &rng, measurement, CV_RAND_NORMAL, cvRealScalar(0),
cvRealScalar(sqrt(kalman->measurement_noise_cov->data.fl[0])) );
/* generate measurement */
cvMatMulAdd( kalman->measurement_matrix, state, measurement, measurement );
measurement_angle = measurement->data.fl[0];
measurement_pt = calc_point(measurement_angle);
/* plot points */
#define draw_cross( center, color, d ) \
cvLine( img, cvPoint( center.x - d, center.y - d ), \
cvPoint( center.x + d, center.y + d ), color, 1, CV_AA, 0); \
cvLine( img, cvPoint( center.x + d, center.y - d ), \
cvPoint( center.x - d, center.y + d ), color, 1, CV_AA, 0 )
cvZero( img );
draw_cross( state_pt, CV_RGB(255,255,255), 3 );
draw_cross( measurement_pt, CV_RGB(255,0,0), 3 );
draw_cross( predict_pt, CV_RGB(0,255,0), 3 );
cvLine( img, state_pt, measurement_pt, CV_RGB(255,0,0), 3, CV_AA, 0 );
cvLine( img, state_pt, predict_pt, CV_RGB(255,255,0), 3, CV_AA, 0 );
cvKalmanCorrect( kalman, measurement );
cvRandArr( &rng, process_noise, CV_RAND_NORMAL, cvRealScalar(0),
cvRealScalar(sqrt(kalman->process_noise_cov->data.fl[0])));
cvMatMulAdd( kalman->transition_matrix, state, process_noise, state );
cvShowImage( "Kalman", img );
code = (char) cvWaitKey( 100 );
if( code > 0 )
break;
}
if( code == 27 || code == 'q' || code == 'Q' )
break;
}
cvDestroyWindow("Kalman");
return 0;
}
#ifdef _EiC
main(1, "kalman.c");
#endif

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samples/cpp/kalman.cpp Normal file
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#include "opencv2/video/tracking.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <stdio.h>
using namespace cv;
static inline Point calcPoint(Point2f center, double R, double angle)
{
return center + Point2f((float)cos(angle), (float)-sin(angle))*(float)R;
}
void help()
{
printf( "\nExamle of c calls to OpenCV's Kalman filter.\n"
" Tracking of rotating point.\n"
" Rotation speed is constant.\n"
" Both state and measurements vectors are 1D (a point angle),\n"
" Measurement is the real point angle + gaussian noise.\n"
" The real and the estimated points are connected with yellow line segment,\n"
" the real and the measured points are connected with red line segment.\n"
" (if Kalman filter works correctly,\n"
" the yellow segment should be shorter than the red one).\n"
"\n"
" Pressing any key (except ESC) will reset the tracking with a different speed.\n"
" Pressing ESC will stop the program.\n"
);
}
int main(int, char**)
{
help();
Mat img(500, 500, CV_8UC3);
KalmanFilter KF(2, 1, 0);
Mat state(2, 1, CV_32F); /* (phi, delta_phi) */
Mat processNoise(2, 1, CV_32F);
Mat measurement = Mat::zeros(1, 1, CV_32F);
char code = (char)-1;
for(;;)
{
randn( state, Scalar::all(0), Scalar::all(0.1) );
KF.transitionMatrix = *(Mat_<float>(2, 2) << 1, 1, 0, 1);
setIdentity(KF.measurementMatrix);
setIdentity(KF.processNoiseCov, Scalar::all(1e-5));
setIdentity(KF.measurementNoiseCov, Scalar::all(1e-1));
setIdentity(KF.errorCovPost, Scalar::all(1));
randn(KF.statePost, Scalar::all(0), Scalar::all(0.1));
for(;;)
{
Point2f center(img.cols*0.5f, img.rows*0.5f);
float R = img.cols/3.f;
double stateAngle = state.at<float>(0);
Point statePt = calcPoint(center, R, stateAngle);
Mat prediction = KF.predict();
double predictAngle = prediction.at<float>(0);
Point predictPt = calcPoint(center, R, predictAngle);
randn( measurement, Scalar::all(0), Scalar::all(KF.measurementNoiseCov.at<float>(0)));
// generate measurement
measurement += KF.measurementMatrix*state;
double measAngle = measurement.at<float>(0);
Point measPt = calcPoint(center, R, measAngle);
// plot points
#define drawCross( center, color, d ) \
line( img, Point( center.x - d, center.y - d ), \
Point( center.x + d, center.y + d ), color, 1, CV_AA, 0); \
line( img, Point( center.x + d, center.y - d ), \
Point( center.x - d, center.y + d ), color, 1, CV_AA, 0 )
img = Scalar::all(0);
drawCross( statePt, Scalar(255,255,255), 3 );
drawCross( measPt, Scalar(0,0,255), 3 );
drawCross( predictPt, Scalar(0,255,0), 3 );
line( img, statePt, measPt, Scalar(0,0,255), 3, CV_AA, 0 );
line( img, statePt, predictPt, Scalar(0,255,255), 3, CV_AA, 0 );
KF.correct(measurement);
randn( processNoise, Scalar(0), Scalar::all(sqrt(KF.processNoiseCov.at<float>(0, 0))));
state = KF.transitionMatrix*state + processNoise;
imshow( "Kalman", img );
code = (char)waitKey(100);
if( code > 0 )
break;
}
if( code == 27 || code == 'q' || code == 'Q' )
break;
}
return 0;
}