Add TOC to PDF from XML/JSON/file?

Question

I currently have a PDF file without any ToC (for example, in Mac's Preview.app, I can't see the ToC in the sidebar).

But I have the TOC in XML format, where there is a title and a pagenumber where that section starts.

Is there any way I can add that TOC to my PDF file in a batch way?

Since I have the TOC in XML, I can basically parse it in any possible way, so if there were a command line to add an TOC item to a PDF, I could also do that.

Any ideas?

Answer 1

It is fairly simple to add bookmarks to a PDF using Ghostscript. The syntax is:

gs -dBATCH -dNOPAUSE -sDEVICE=pdfwrite -sOutputFile=out.pdf in.pdf pdfmarks

Where pdfmarks is a text file with contents like:

[/Title (Title Page) /Page 1 /OUT pdfmark
[/Title (Table of Contents) /Page 3 /OUT pdfmark
...

For nested levels, use the /Count attribute. For example:

[/Count 3 /Title (Chapter 1) /Page 1 /OUT pdfmark
[/Count -2 /Title (Section 1.1) /Page 2 /OUT pdfmark
[/Title (Section 1.1.1) /Page 3 /OUT pdfmark
[/Title (Section 1.1.2) /Page 4 /OUT pdfmark
[/Count -1 /Title (Section 1.2) /Page 5 /OUT pdfmark
[/Title (Section 1.2.1) /Page 6 /OUT pdfmark
[/Title (Section 1.3) /Page 7 /OUT pdfmark

The argument to /Count gives the number of immediately subordinate bookmarks. The sign of the argument sets the default display (negative for closed, positive for open).

If the bookmarks are not enough as a Table of Contents, there exist applications that create a Table of Contents from bookmarks. I haven't used any such, but googling turned up for example Mapsoft TOCBuilder which is a commercial Adobe Acrobat plug-in with trial.

Sources :
PDF bookmarks with Ghostscript
How to generate bookmarks via ghostscript/pdfwrite/pdfmark

Answer 2

If you have just one file, here's a way you can do so using pdfTeX. It may be slightly convoluted but I know TeX (and don't know other tools) and it does the trick when I need it.

Here's a sample file which will copy the full contents of your input.pdf and adds a Table of Contents containing links to some page numbers.

% Set page size... this is A4, change to whatever you need
\pdfpagewidth=210mm
\pdfpageheight=297mm

% TeX always adds unwanted 1in left and top margins, this counteracts them.
\advance\hoffset by -1in
\advance\voffset by -1in

% This macro inserts a verbatim copy of one page from the source into the output.
\def\copypage#1{%
  \pdfximage page #1 {input.pdf}%
  \shipout\vbox{\pdfrefximage\pdflastximage}}

% Determine the total number of pages
\pdfximage{input.pdf}
\newcount\total
\total=\pdflastximagepages

% Define an iterator to copy the whole file
\def\copy{%
  \copypage{\the\pageno} % Copy the page given by current page number
  \advance\pageno by 1 % Increase page number by one
  \ifnum\pageno > \total
    \let\copy\relax % After the last page has been copied, stop
  \fi
  \copy} % This repeats the cycle until \copy is redefined to \relax at the very end

\copy % Run the cycle

% Here you add your outline
\pdfoutline goto page 1 {/Fit} count 2 {Chapter}
  \pdfoutline goto page 1 {/Fit} count -3 {Section}
    \pdfoutline goto page 1 {/Fit} {Item}
    \pdfoutline goto page 2 {/Fit} {Item}
    \pdfoutline goto page 3 {/Fit} {Item}
  \pdfoutline goto page 4 {/Fit} count 1 {Section}
    \pdfoutline goto page 4 {/Fit} count -2 {Subection}
      \pdfoutline goto page 1 {/Fit} {Item}
      \pdfoutline goto page 5 {/Fit} {Item}

\end

How to use the \pdfoutline command:

• Always supply a page number, even for section headers which might not be supposed to be used directly
• Replace "Chapter", "Item" etc. by your desired headers
• Supply a count for items which contain subitems (note that there's no "closing" command so TeX needs to know the count in advance)
• EDIT thanks to harrymc: Make the count negative if you want a item with subitems closed by default, leave it positive if you want it open

After preparing this input file, save it as, say, output.tex, and process it using pdftex. Voilà, this produces output.pdf with your shiny new ToC.