- write_keyword_value(s, "BITPIX", bitpix, &lines_written); // no of bits per pixel
- write_keyword_value(s, "NAXIS", naxis, &lines_written); // no of dimensions of image
- write_keyword_value(s, "NAXIS1", encctx->width, &lines_written); // first dimension i.e. width
- write_keyword_value(s, "NAXIS2", encctx->height, &lines_written); // second dimension i.e. height
+ write_keyword_value(s, "%d", "BITPIX", &bitpix, &lines_written); // no of bits per pixel
+ write_keyword_value(s, "%d", "NAXIS", &naxis, &lines_written); // no of dimensions of image
+ write_keyword_value(s, "%d", "NAXIS1", &encctx->width, &lines_written); // first dimension i.e. width
+ write_keyword_value(s, "%d", "NAXIS2", &encctx->height, &lines_written); // second dimension i.e. height