Shell – Implementing a String -> PDF Stamp tool

From http://blog.chewearn.com/2008/12/18/rearrange-pdf-pages-with-pdftk/

pdftk A=src.pdf B=blank.pdf cat A1 B1 A2-end output res.pdf

Hope you like this script, just save it as pdfInsertBlankPageAt.sh, add execute permissions, and run.

./pdfInsertBlankPageAt 5 src.pdf res.pdf

#!/bin/bash
if [ $# -ne 3 ]
then
  echo "Usage example: ./pdfInsertBlankPageAt 5 src.pdf res.pdf"
  exit $E_BADARGS
else
  pdftk A=$2 B=blank.pdf cat A1-$(($1-1)) B1 A$1-end output $3
fi 

cat A1 B1 A2-end means that the output file will contain the first page of document A (src.pdf) followed by the first page of document B (blank.pdf) followed by the rest (pages 2 to end) of document B. This operation is called concatenation, Linux cat is very often used to display text, but it is interesting when used with more than one argument.

To create blank.pdf, see How do I create a blank PDF from the command line?

Well, I've come up with a solution using TikZ within a crafted LaTex document. The result is not exactly the same, but I think it is even nicer:

This required having a tex document with placeholders that will be replaced by the arguments to a sh script.

% file: add_legend.tex

\documentclass{standalone}
\usepackage{graphicx}

\usepackage{tikz}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% LaTeX Overlay Generator - Annotated Figures v0.0.1
% Created with (omitted http) ff.cx/latex-overlay-generator/
% If this generator saves you time, consider donating 5,- EUR! :-)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\annotatedFigureBoxCustom{bottom-left}{top-right}{label}{label-position}{box-color}{label-color}{border-color}{text-color}
\newcommand*\annotatedFigureBoxCustom[8]{\draw[#5,thick,rounded corners] (#1) rectangle (#2);\node at (#4) [fill=#6,thick,shape=circle,draw=#7,inner sep=4pt,font=\huge\sffamily,text=#8] {\textbf{#3}};}
%\annotatedFigureBox{bottom-left}{top-right}{label}{label-position}
\newcommand*\annotatedFigureBox[4]{\annotatedFigureBoxCustom{#1}{#2}{#3}{#4}{white}{white}{black}{black}}
\newcommand*\annotatedFigureText[4]{\node[draw=none, anchor=south west, text=#2, inner sep=0, text width=#3\linewidth,font=\sffamily] at (#1){#4};}
\newenvironment {annotatedFigure}[1]{\centering\begin{tikzpicture}
\node[anchor=south west,inner sep=0] (image) at (-0.75,-0.75) { #1};\begin{scope}[x={(image.south east)},y={(image.north west)}]}{\end{scope}\end{tikzpicture}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}  

  \begin{annotatedFigure}           
        {\includegraphics[width=1.0\linewidth]{_image_}}    
        \annotatedFigureBox{0,0}{0.000,0.0}{_letter_}{0,0}%bl
    \end{annotatedFigure}  

\end{document}

And the sh script:

#!/bin/sh
# Call this script with at least 2 parameters, for example
# sh scriptname <image_file> <letter_of_legend> 

cat add_legend.tex | sed "s/_image_/$1/g" | sed "s/_letter_/$2/g" | pdflatex

#rename output to match <letter_of_legend>_<image_file> format
mv texput.pdf $2_$1 

#clean up
rm texput.*

exit 0

Finnaly, by calling:

$> ./legend.sh online_gauss.pdf A

the output drawn in "A_online_gauss.pdf"!