      return dt;
    }

    // Return a temporary string describing the size of a memory buffer.
    inline const char *strbuffersize(const cimg_ulong size) {
      static CImg<char> res(256);
      cimg::mutex(5);
      if (size<1024LU) cimg_snprintf(res,res._width,"%lu byte%s",(unsigned long)size,size>1?"s":"");
      else if (size<1024*1024LU) { const float nsize = size/1024.f; cimg_snprintf(res,res._width,"%.1f Kio",nsize); }
      else if (size<1024*1024*1024LU) {
        const float nsize = size/(1024*1024.f); cimg_snprintf(res,res._width,"%.1f Mio",nsize);
Unknown