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LaTeX

PDF Metadata

PDF/A-1b compliance

PDF/A is an ISO-standardized version of the Portable Document Format (PDF) specialized for use in the archiving. PDF/A differs from PDF by prohibiting features unsuitable for long-term archiving, such as font linking (as opposed to font embedding) and encryption. The level B "basic" conformance requires only that standards necessary for the reliable reproduction of a document's visual appearance be followed.1

PDF/A compliance can be checked with Acrobat Reader or veraPDF.

According to this answer on Stack Overflow, a PDF/A-compliant PDF could be generated using LuaLaTeX using the following code:

\usepackage[pdfa]{hyperref}
\usepackage{hyperxmp}

\hypersetup{pdfapart=1, pdfaconformance=B} % PDF/A-1b

% Add an `OutputIntent` to PDF metadata to correctly specify colours
\immediate\pdfobj stream attr{/N 3} file{sRGB.icc}
\pdfcatalog{%
  /OutputIntents [
    <<
      /Type /OutputIntent
      /S /GTS_PDFA1
      /DestOutputProfile \the\pdflastobj\space 0 R
      /OutputConditionIdentifier (sRGB)
      /Info (sRGB)
    >>
  ]
}

However, adding this code snippet to my PhD manuscript did not enable it to pass the validation test with veraPDF. On the other hand, the University Lyon1 archive service, only accepts PDF/A-1b documents and accepted the version generated with Firefox's "Print as PDF", even though it also failed the test.

Graphics

Include PDF

PDFs can be included in a LaTeX documents using the \includepdf command from the pdfpages packages:

\usepackage{pdfpages}
\includepdf[pages={1,3-5,7},scale=0.8]{path/to/doc.pdf}

To include a PDF in a document page that has a section title such as \sectionor \chapter, one should utilize the pagecommand option. This option declares a LaTeX command that is executed on each page of the included PDF:

\ìncludepdf[scale=0.8,pagecommand={\section{Example}\hfill}]{path/to/doc.pdf}

Given that the command is executed on each page, if one wishes to include a multipage PDF, two imports are necessary: one with the section including only the first page of the PDF, and a second one without the option to include the rest of the PDF:

\includepdf
  [pages=1,scale=0.8,pagecommand={\section{Example}\hfill}]
  {path/to/doc.pdf}
\includepdf
  [pages=2-,scale=0.8,pagecommand={}]{path/to/doc.pdf}

The empty pagecommand={} is employed here to ensure that the LaTeX header and footer (such as the page number), are present on the pages where the PDF is included.

Code highlighting with Minted

The minted package provides syntax highlighting for code listing (and inline code) using the Pygments library. It requires running system command, i.e. shell escape, which can be enabled in .latexmkrc

$pdf_mode = 4; # LuaLaTeX
$pdflatex = "pdflatex -shell-escape %O %S";
$lualatex = "lualatex --shell-escape %O %S";
$out_dir = "build";
$quiet = 1;

or directly from the command line as in lualatex --shell-escape main.tex. Also, if using an alternative path for the build files (as in the above Latexmk configuration), Minted caching should be disabled and the path must be specified:

\usepackage[cache=false,outputdir=./build]{minted}

Minted in Beamer

minted listings and Beamer overlays may not interact well

Verbatim-like content conflicts with how processes overlays. Consider alternatives such as using multiples frames or uncovering entier code blocks.

In Beamer, frames containing minted environments must be marked as fragile due to verbatim-like content:

\documentclass{beamer}
\usepackage{minted}
\begin{document}
  \begin{frame}[fragile]{Minted example}
    \begin{minted}[fontsize=\scriptsize, linenos]{cuda}
    __global__ void cudaHello(){
      printf("Hello World from GPU!\n");
    }

    int main() {
      cudaHello<<<1,1>>>();
      return 0;
    }
    \end{minted}
  \end{frame}
\end{document}

  1. Wikipedia contributors,"PDF/A," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/w/index.php?title=PDF/A&oldid=1172480804 (accessed October 9, 2023). ↩