code: public long getImageSize() {
      long x = 0, y = 0;
      if (tags.containsTagId(TiffTags.getTagId("ImageLength")))
        x = tags.get("ImageLength").getFirstNumericValue();
      if (tags.containsTagId(TiffTags.getTagId("ImageWidth")))
        y = tags.get("ImageWidth").getFirstNumericValue();
      return x * y;
    }
docs: Gets the image size (x*y).
  
  @return the image size