Cycle through all the pixels and obtain the number of black and white pixels in an image

Question

could you help me, you can tell me what I'm wrong with, my code has 2 for's that run through a whole 157x127 pixel image, from which I get black and white through RGB; in turn I have 2 counters of those two colors.

As I understand it, if the 157x127 measurement gives 19,939 pixels, of which there is black and white; but adding the counters gives me less (14218 for white and 5643 for black). Where am I wrong or is my logic wrong?

Add the image:

enter image description here

The application does not close itself

Code below:

BitmapDrawable drawable = (BitmapDrawable) imgviewREXMorphologEX.getDrawable();
Bitmap bitmap = drawable.getBitmap();

int Width = bitmap.getWidth();
int Height = bitmap.getHeight();

int contadorB = 0;
int contadorN = 0;

for (int x = 0; x <= Width - 1; x++) {
    int xi = x;
    for (int y = 0; y <= Height - 1; y++) {
        int yi = y;

        int coordenada = bitmap.getPixel(xi, yi);// pixel
        double r = Color.red(coordenada);
        double g = Color.green(coordenada);
        double b = Color.blue(coordenada);

        if (r == 255 && g == 255 && b == 255) {
            contadorB++;
        } else if (r == 0 && g == 0 && b == 0) {
            contadorN++;
        }
        txtviewcolor3.setText(contadorB + " - " + contadorN + " - " + (contadorB + contadorN) + " - " + (Width * Height));

    }
}

Answer 1

Add an else clause to your if statements, and see if there are actually some other colours in the image?

Answer 2

Your image is not just black or white!

See here an amplified section (800%, bottom right):

There are some pixels that are gray (brighter and darker ones). Depending on purpose, some limits can help (e.g. r < MIN && g < MIN && b < 10) or using the Formula to determine brightness of RGB color compared to some limit(s)