Make all pixels with transparency black, and remove their alpha channel on Android Bitmap

AlphaToBlack

// For input image where information is only stored in alpha channel over black RGB.
// Make all pixels with transparency black, and remove alpha channel.

    private Bitmap AlphaToBlack(Bitmap image) {
        Bitmap rgbImage = image.copy(Bitmap.Config.ARGB_8888, true);
        
        for (int y = 0; y < rgbImage.getHeight(); y++) {
        	for (int x = 0; x < rgbImage.getWidth(); x++) {
        		int aPixel = rgbImage.getPixel(x, y);
        		if (rgbImage.getPixel(x, y) < 0xFF000000)
        			rgbImage.setPixel(x, y,  0xFF000000);
        	}
        }
        return rgbImage;
    }