detect HSV color for skin color and extract the color in that region

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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 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() + "" );

    // 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.