The portable document format (PDF) has arguably become the most common format used for distribution of documents. In practice, a PDF file is just a compiled PostScript file. For a more complete introduction, please see Recognized file formats. To provide high quality graphics, the PDF is a vectorized format, therefore pixels (elements of a “rasterized” format) aren’t defined in their context. As a result, similar to EPS files (eps.h), Gnuastro only writes datasets to a PDF file, not vice-versa.
name has an PDF suffix. This can be used to make
sure that a given input file is PDF. See
gal_pdf_suffix_is_pdf for a
list of recognized suffixes.
suffix is a recognized PDF suffix. The recognized
in dataset into an EPS file called
in has to be an unsigned 8-bit character type
GAL_TYPE_UINT8, see Numeric data types). The desired width of
the image in human/non-pixel units (to help the displayer) can be set with
widthincm argument. If
borderwidth is non-zero, it is
interpreted as the width (in points) of a solid black border around the
image. A border can helpful when importing the PDF file into a document.
This function is just a wrapper for the
gal_eps_write function in
EPS files (eps.h). After making the EPS file, Ghostscript (with a version of
9.10 or above, see Optional dependencies) will be used to compile the
EPS file to a PDF file. Therefore if GhostScript doesn’t exist, doesn’t have
the proper version, or fails for any other reason, the EPS file will
remain. It can be used to find the cause, or use another converter or
By default, when the dataset only has two values, this function will use the PostScript optimization that allows setting the pixel values per bit, not byte (Recognized file formats). This can greatly help reduce the file size. However, when dontoptimize!=0, this optimization is disabled: even though there are only two values (is binary), the difference between them does not correspond to the full contrast of black and white.