A LaTeX file for extracting slides from handouts

gistfile1.sh

n=9;for i in `seq $n`; do pages=$(identify wyklad$i.pdf | tail -n 1 | perl -ne '/^wyklad.*?\[(\d+)/; $_ = $1+1; print'); sed -e s/wyklad1/wyklad$i/g -e s/23/$pages/ < slides.tex > slides$i.tex; done

slides.tex

\documentclass[a4paper]{article}
\usepackage[landscape,margin=0pt]{geometry}
\usepackage{graphicx,ifthen,calc}

\def\filename{wyklad1}
\def\slidescount{23}

\newcounter{pagecounter}
\newcommand*\insertgraphicsfiles[2]{
  \setcounter{pagecounter}{#1-1}
  \whiledo{\value{pagecounter}<#2}{
    \stepcounter{pagecounter}
    \includegraphics[height=\textheight,viewport=57 569 287 741,clip,%
      page=\the\value{pagecounter}]{\filename}
    \includegraphics[height=\textheight,viewport=57 335.5 287 507.5,clip,%
      page=\the\value{pagecounter}]{\filename}
    \includegraphics[height=\textheight,viewport=57 101.5 287 273.5,clip,%
      page=\the\value{pagecounter}]{\filename}
  }
}

\pagestyle{empty}

\begin{document}
\begin{center}
\insertgraphicsfiles{1}{\slidescount}
\end{center}
\end{document}