The following is the code that I run to find the face region
private Mat mRgbMat;
private Mat mHsvMat;
private Mat mMaskMat;
private int channelCount = 3;
private Mat mDilatedMat;
private List<MatOfPoint> contours = new ArrayList<MatOfPoint>();
private Mat hierarchy;
private int iLineThickness = 5;
private org.opencv.core.Scalar colorGreen = new Scalar(0, 255, 0);
private static double mMinContourArea = 0.3;
private List<MatOfPoint> mMaxContours = new ArrayList<MatOfPoint>();
private void detectRegion() {
//get the image from gallery and change it into bitmap
Bitmap bmpTemp = originalImg.copy(Bitmap.Config.ARGB_8888, true);
Utils.bitmapToMat(bmpTemp, mRgbMat);
Imgproc.cvtColor(mRgbMat, mHsvMat, Imgproc.COLOR_RGB2HSV, channelCount);
Scalar lowerThreshold = new Scalar(0, 0.23 * 255, 50); // Blue color – lower hsv values
Scalar upperThreshold = new Scalar(50, 0.68 * 255, 255); // Blue color – higher hsv values
Core.inRange(mHsvMat, lowerThreshold, upperThreshold, mMaskMat);
Imgproc.dilate(mMaskMat, mDilatedMat, new Mat());
Imgproc.findContours(mMaskMat, contours, hierarchy, Imgproc.RETR_EXTERNAL, Imgproc.CHAIN_APPROX_SIMPLE);
// Find max contour area
double maxArea = 0;
Iterator<MatOfPoint> each = contours.iterator();
while (each.hasNext()) {
MatOfPoint wrapper = each.next();
double area = Imgproc.contourArea(wrapper);
if (area > maxArea)
maxArea = area;
}
// Filter contours by area and resize to fit the original image size
mMaxContours.clear();
each = contours.iterator();
while (each.hasNext()) {
MatOfPoint contour = each.next();
if (Imgproc.contourArea(contour) > mMinContourArea*maxArea) {
mMaxContours.add(contour);
}
}
Imgproc.drawContours(mRgbMat, mMaxContours,0, colorGreen, iLineThickness);
Log.d(TAG + " contours" , contours.size() + "" );
Log.d(TAG + " contours" , mMaxContours.size() + "" );
Log.d(TAG + " contours row col" , mMaxContours.get(0).toList().toString());
Log.d(TAG + " contours " , mMaxContours.get(0).toString());
counter++;
// convert to bitmap:
Bitmap bm = Bitmap.createBitmap(mRgbMat.cols(), mRgbMat.rows(), Bitmap.Config.ARGB_8888);
Utils.matToBitmap(mRgbMat, bm);
// find the imageview and draw it!
imageView.setImageBitmap(bm);
}
Result of the above code:
please add https:// because I cannot post link. Thank you s11.postimg.org/myaf9fb4z/photo_2017_02_16_14_43_34.jpg
Although I can get a good result using the above function, I may not get the result that I want if there are some extra elements that contains a close value of the color like the following image.
please add https:// because I cannot post link. Thank you s27.postimg.org/gy04nnwzn/photo_2017_02_16_14_49_57.jpg
How do I change my code to fit this situation? Also I need to change the HSV value in this region. How can I get the HSV value in that region? Please give me some helps. Thank you very much.
