JavaCV : Tracking objects using the Camshift algorithm - opencv

Question

I want to track objects using the Camshift algorithm. I tried to correct the bugs that I found in the JavaCV translation of the original OpenCV Camshift file.
Here is my code:
package objectTracking;
import com.googlecode.javacv.CanvasFrame;
import com.googlecode.javacv.FrameGrabber;
import com.googlecode.javacv.OpenCVFrameGrabber;
import static com.googlecode.javacv.cpp.opencv_core.*;
import com.googlecode.javacv.cpp.opencv_core.CvBox2D;
import com.googlecode.javacv.cpp.opencv_core.CvPoint;
import com.googlecode.javacv.cpp.opencv_core.CvRect;
import com.googlecode.javacv.cpp.opencv_core.CvScalar;
import com.googlecode.javacv.cpp.opencv_core.IplImage;
import com.googlecode.javacv.cpp.opencv_core.IplImageArray;
import static com.googlecode.javacv.cpp.opencv_imgproc.*;
import com.googlecode.javacv.cpp.opencv_imgproc.CvConnectedComp;
import com.googlecode.javacv.cpp.opencv_imgproc.CvHistogram;
import static com.googlecode.javacv.cpp.opencv_video.*;
import com.sun.jna.ptr.FloatByReference;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class CamShifter implements MouseListener{
final static int MOUSE_PRESSED = 1;
final static int MOUSE_RELEASED = 2;
IplImage image, frame, hsv, hue, mask, backproject, histimg;
IplImageArray hueArray;
CvHistogram hist;
CanvasFrame histogram = new CanvasFrame("Histogram"), camshiftDemo = new CanvasFrame("CamshiftDemo");
boolean backproject_mode = false;
boolean select_object = false;
int track_object = 0;
boolean show_hist = true;
boolean paused = false;
CvPoint origin = new CvPoint();
CvRect selection = new CvRect();
OpenCVFrameGrabber grabber = new OpenCVFrameGrabber(0);
CvRect track_window = new CvRect();
CvBox2D track_box = new CvBox2D();
CvConnectedComp track_comp = new CvConnectedComp();
int hsize = 16;
float hranges[] = {0,180};
int[] hdims = {hsize};
float hranges_arr[][] = {hranges};
int vmin = 10, vmax = 256, smin = 30;
public static void main(String args[]) throws Exception {
CamShifter csh = new CamShifter();
csh.work(csh);
System.out.println("CamShiftDetector trial");
}
public CamShifter() throws FrameGrabber.Exception {
grabber.start();
camshiftDemo.getCanvas().addMouseListener(this);
}
public void onMouse(int event, int x, int y) {
if (select_object) {
//get selection
int selX, selY, selW, selH;
selX = Math.min(x, origin.x());
selY = Math.min(y, origin.y());
selW = selX + Math.abs(x - origin.x());
selH = selY + Math.abs(y - origin.y());
selection = cvRect(selX, selY, selW, selH);
System.out.println("Selection : \n("+selX+", "+selY+")\n("+selW+", "+selH+")");
//ensure that selection is enclosed within the image
selX = Math.max(selection.x(), 0);
selY = Math.max(selection.y(), 0);
selW = Math.min(selection.width(), image.width());
selH = Math.min(selection.height(), image.height());
selection = cvRect(selX, selY, selW - selX, selH - selY);
System.out.println("ensure that selection is enclosed within the image");
System.out.println("Selection : \n("+selX+", "+selY+")\n("+selW+", "+selH+")");
}
switch (event) {
case MOUSE_PRESSED:
origin = cvPoint(x, y);
selection = cvRect(x, y, 0, 0);
select_object = true;
break;
case MOUSE_RELEASED:
select_object = false;
if (selection.width() > 0 && selection.height() > 0) {
track_object = -1;
}
break;
}
}
CvScalar hsv2rgb(float hue) {
int[] rgb = new int[3];
int p, sector;
int[][] sector_data = {{0, 2, 1}, {1, 2, 0}, {1, 0, 2}, {2, 0, 1}, {2, 1, 0}, {0, 1, 2}};
hue *= 0.033333333333333333333333333333333f;
sector = (int) Math.floor(hue);
p = Math.round(255 * (hue - sector));
p = p ^ 1;
int temp = 0;
if ((sector & 1) == 1) {
temp = 255;
} else {
temp = 0;
}
p ^= temp;
rgb[sector_data[sector][0]] = 255;
rgb[sector_data[sector][1]] = 0;
rgb[sector_data[sector][2]] = p;
return cvScalar(rgb[2], rgb[1], rgb[0], 0);
}
String coffee;
public void work(CamShifter csh) throws Exception {
IplImage capture = grabber.grab();
System.out.println("paused = "+paused);
if (capture == null) {
System.out.println("Could not initialize capturing...\n");
return;
}
while (true) {
int bin_w;
if (!paused) {
frame = grabber.grab();
if (frame == null) {
return;
}
}
if (image == null) {
image = cvCreateImage(frame.cvSize(), 8, 3);
hsv = cvCreateImage(frame.cvSize(), 8, 3);
hue = cvCreateImage(frame.cvSize(), 8, 1);
mask = cvCreateImage(frame.cvSize(), 8, 1);
backproject = cvCreateImage(frame.cvSize(), 8, 1);
histimg = cvCreateImage(cvSize(320, 200), 8, 3);
cvZero(histimg);
hist = cvCreateHist( 1, hdims, CV_HIST_ARRAY, hranges_arr, 1 );
}
cvCopy(frame, image);
if (!paused)
{
cvCvtColor(image, hsv, CV_BGR2HSV);
if (track_object != 0) {
int _vmin = vmin, _vmax = vmax;
cvInRangeS(hsv, cvScalar(0, smin, Math.min(_vmin, _vmax), 0), cvScalar(180, 256, Math.max(_vmin, _vmax), 0), mask);
cvSplit(hsv, hue, null, null, null);
hueArray = new IplImageArray(hue);
if (track_object < 0) {
float max_val = 0.f;
cvSetImageROI(hue, selection);
cvSetImageROI(mask, selection);
cvCalcHist(hueArray, hist, 0, null);
if (max_val != 0) { // TODO: entier non null == true en C, à vérifier
max_val = (float) 255. / max_val;
} else {
max_val = 0;
}
FloatByReference fl_ref = new FloatByReference(max_val);
cvConvertScale(hist.bins(), hist.bins(), Float.parseFloat(fl_ref.toString()), 0);
cvResetImageROI(hue);
cvResetImageROI(mask);
track_window = selection;
track_object = 1;
cvZero(histimg);
bin_w = histimg.width() / hsize;
for (int i = 0; i < hsize; i++) {
int val = Math.round((int) (cvGetReal1D(hist.bins(), i) * histimg.height() / 255.));
CvScalar color = hsv2rgb(i * 180.f / hsize);
cvRectangle(histimg, cvPoint(i * bin_w, histimg.height()), cvPoint((i + 1) * bin_w, histimg.height() - val), color, -1, 8, 0);
}
}
cvCalcBackProject(hueArray, backproject, hist);
cvAnd(backproject, mask, backproject, null);
cvCamShift(backproject, track_window, cvTermCriteria(CV_TERMCRIT_EPS | CV_TERMCRIT_ITER, 10, 1), track_comp, track_box);
track_window = track_comp.rect();
// if (track_window.width()*track_window.height()<=1)
// {
// int cols = backproject.width(), rows = backproject.height(), r = (Math.min(cols, rows)+5)/6;
// track_window = cvRect(
// Math.max(track_window.x()-r,0),
// Math.max(track_window.y()-r,0),
// Math.min(track_window.x()+r,cols),
// Math.min(track_window.y()+r,rows));
// }
if (backproject_mode) {
cvCvtColor(backproject, image, CV_GRAY2BGR);
}
if (image.origin() == 0) {
track_box = track_box.angle(-track_box.angle());
cvEllipseBox(image, track_box, cvScalar(0, 0, 255, 0), 3, CV_AA, 0);
}
}
} else if (track_object < 0) {
paused = false;
}
if (select_object && selection.width() > 0 && selection.height() > 0) {
cvSetImageROI(image, selection);
cvXorS(image, cvScalarAll(255), image, null);
cvResetImageROI(image);
}
camshiftDemo.showImage(image);
histogram.showImage(histimg);
}
}
#Override
public void mouseClicked(MouseEvent e) {
// System.out.println("Mouse Clicked !");
}
#Override
public void mousePressed(MouseEvent e) {
this.onMouse(MOUSE_PRESSED, e.getX(), e.getY());
System.out.println("Mouse Pressed !");
System.out.println("\t e.getX(): "+e.getX());
System.out.println("\t e.getY(): "+e.getY());
}
#Override
public void mouseReleased(MouseEvent e) {
this.onMouse(MOUSE_RELEASED, e.getX(), e.getY());
System.out.println("Mouse Released !");
System.out.println("\t e.getX(): "+e.getX());
System.out.println("\t e.getY(): "+e.getY());
}
#Override
public void mouseEntered(MouseEvent e) {
// System.out.println("Mouse Entered !");
}
#Override
public void mouseExited(MouseEvent e) {
// System.out.println("Mouse Exited !");
}
}
Everytime I run the application, and after I select my object to track, the JVM crashes when getting to the line containing cvCalcHist.
Can anyone please tell me what's wrong with my code. I've been on it since days and I can't figure out the problem with it :(
Thank you very much.