    static CImg<T> get_load_png(std::FILE *const file, unsigned int *const bits_per_value=0) {
      return CImg<T>().load_png(file,bits_per_value);
    }
    static CImg<T> get_load_png(std::FILE *const file, unsigned int *const bits_per_value=0) {
      return CImg<T>().load_png(file,bits_per_value);
    }