public boolean hasChanges(Mat current) {
int PIXEL_DIFF_THRESHOLD = 5;
int IMAGE_DIFF_THRESHOLD = 5;
Mat bg = new Mat();
Mat cg = new Mat();
Mat diff = new Mat();
Mat tdiff = new Mat();
Imgproc.cvtColor(base, bg, Imgproc.COLOR_BGR2GRAY);
Imgproc.cvtColor(current, cg, Imgproc.COLOR_BGR2GRAY);
Core.absdiff(bg, cg, diff);
Imgproc.threshold(diff, tdiff, PIXEL_DIFF_THRESHOLD, 0.0, Imgproc.THRESH_TOZERO);
if (Core.countNonZero(tdiff) <= IMAGE_DIFF_THRESHOLD) {
return false;
}
Imgproc.threshold(diff, diff, PIXEL_DIFF_THRESHOLD, 255, Imgproc.THRESH_BINARY);
Imgproc.dilate(diff, diff, new Mat());
Mat se = Imgproc.getStructuringElement(Imgproc.MORPH_ELLIPSE, new Size(5, 5));
Imgproc.morphologyEx(diff, diff, Imgproc.MORPH_CLOSE, se);
List<MatOfPoint> points = new ArrayList<MatOfPoint>();
Mat contours = new Mat();
Imgproc.findContours(diff, points, contours, Imgproc.RETR_LIST, Imgproc.CHAIN_APPROX_SIMPLE);
int n = 0;
for (Mat pm : points) {
log(lvl, "(%d) %s", n++, pm);
printMatI(pm);
}
log(lvl, "contours: %s", contours);
printMatI(contours);
return true;
}
public Mat onCameraFrame(CvCameraViewFrame inputFrame) {
mRgba = inputFrame.rgba();
// convert to Gray scale
Imgproc.cvtColor(mRgba, img_gray, Imgproc.COLOR_BGR2GRAY);
// make it binary with threshold=100
Imgproc.threshold(img_gray, erd, 100, 255, Imgproc.THRESH_OTSU);
// remove pixel noise by "erode" with structuring element of 9X9
Mat erode = Imgproc.getStructuringElement(Imgproc.MORPH_ERODE, new Size(9, 9));
Imgproc.erode(erd, tgt, erode);
// apply "dilation" to enlarge object
Mat dilate = Imgproc.getStructuringElement(Imgproc.MORPH_DILATE, new Size(9, 9));
Imgproc.dilate(tgt, erd, dilate);
// take a window
Size s = erd.size();
int W = (int) s.width;
int H = (int) s.height;
Rect r = new Rect(0, H / 2 - 100, W, 200);
Mat mask = new Mat(s, CvType.CV_8UC1, new Scalar(0, 0, 0));
rectangle(mask, r.tl(), r.br(), new Scalar(255, 255, 255), -1);
erd.copyTo(window, mask);
// find the contours
Imgproc.findContours(window, contours, dest, 0, 2);
// find largest contour
int maxContour = -1;
double area = 0;
for (int i = 0; i < contours.size(); i++) {
double contArea = Imgproc.contourArea(contours.get(i));
if (contArea > area) {
area = contArea;
maxContour = i;
}
}
// form bounding rectangle for largest contour
Rect rect = null;
if (maxContour > -1) rect = Imgproc.boundingRect(contours.get(maxContour));
// position to center
while (!train) {
if (rect != null) {
Imgproc.rectangle(mRgba, rect.tl(), rect.br(), new Scalar(255, 255, 255), 5);
if ((rect.x + rect.width / 2) > W / 2 - 20 && (rect.x + rect.width / 2) < W / 2 + 20) {
runOnUiThread(
new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(), "OK", Toast.LENGTH_SHORT).show();
}
});
train = true;
}
}
if (contours != null) contours.clear();
return mRgba;
}
if (train) {
if (rect != null) {
Imgproc.rectangle(mRgba, rect.tl(), rect.br(), new Scalar(255, 255, 255), 5);
// direction of movement
int thr = 100;
if ((rect.x + rect.width / 2) < (W / 2 - thr)) {
// move to the RIGHT
uHandler.obtainMessage(MainActivity.LEFT).sendToTarget();
} else {
if ((rect.x + rect.width / 2) > (W / 2 + thr)) {
uHandler.obtainMessage(MainActivity.RIGHT).sendToTarget();
} else {
uHandler.obtainMessage(MainActivity.FORWARD).sendToTarget();
}
}
} else {
// stop moving
uHandler.obtainMessage(MainActivity.STOP).sendToTarget();
}
}
if (contours != null) contours.clear();
return mRgba;
}
