code: private static Bitmap checkSource(Bitmap original, int radius) {
          if (radius < 0 || radius > 256) {
              throw new RuntimeException("Blur bitmap radius must >= 1 and <=256.");
          }
  
          // First we should check the original
          if (original == null) {
              throw new NullPointerException("Blur bitmap original isn't null.");
          }
          if (original.isRecycled()) {
              throw new RuntimeException("Blur bitmap can't blur a recycled bitmap.");
          }
  
          Bitmap.Config config = original.getConfig();
          if (config != Bitmap.Config.ARGB_8888 && config != Bitmap.Config.RGB_565) {
              throw new RuntimeException("Blur bitmap only supported Bitmap.Config.ARGB_8888 and Bitmap.Config.RGB_565.");
          }
  
          return (original);
      }
docs: Building the bitmap
  
  @param original Bitmap
  @return Bitmap