Extract all \note tags from beamer as a simple text file

Question

There is a nice presenter tool I am using called pdfpc.

Sadly it does not show notes I put in my latex presentation with \note{}.

Is there a way to extract the content of all my \note{} tags to a file that I can convert to a format readable by pdfpc then?

Answer 1

I came up with a quite nice solution I created based on these two questions on file IO:

• File input and output
• How can I open a file in “append” mode?

Here is the code to put before \begin{document}:

% create a new file handle
\newwrite\pdfpcnotesfile

% open file on \begin{document}
\AtBeginDocument{%
    \immediate\openout\pdfpcnotesfile\jobname.pdfpc\relax
    \immediate\write\pdfpcnotesfile{[notes]}
}
% define a # https://tex.stackexchange.com/a/37757/10327
\begingroup
    \catcode`\#=12
    \gdef\hashchar{#}%
\endgroup
% define command \pnote{} that works exactly like \note but
% additionally writes notes to file in pdfpc readable format
\newcommand{\pnote}[1]{%
    % keep normal notes working
    \note{#1}%
    % write notes to file
    \begingroup
        \let\#\hashchar
        \immediate\write\pdfpcnotesfile{\#\#\# \theframenumber}%
        \immediate\write\pdfpcnotesfile{\unexpanded{#1}}%
    \endgroup
}
% close file on \end{document}
\AtEndDocument{%
    \immediate\closeout\pdfpcnotesfile
}

You can then use the \pnote{} command like you used \note{} before. The behavior will be the same but it will additionally write notes to file in pdfpc readable format.

There are a few thing not yet working:

• It does not preserve newlines, so everything in a \pnote will end up in one line of the output file. To replace newlines and pars you may use the following commands:

  • sed -i "s/\\\\\\\\/\n/g" slides.pdfpc
  • sed -i "s/\\\\par/\n\n/g" slides.pdfpc

• Multiple \pnote{} commands per frame are not working right now.