Adding crop marks to existing PDF files

Question

I'm kind of new to all the PDF crop/bleed/trim technicalities... but what I have is business cards in PDF format of about 9 x 5 cm. I just want to add the bleed and crop marks, or if not bleed margins then at least just the crop marks, at specified mm from the edges.

1. Is there anyway I can do this programmatically in linux? Like maybe by using pdftk or ghostscript or imagemagick or some php library? By crop marks I mean the little lines at each corner of the document. Is it possible to maybe just draw lines on the PDF using imagemagick, if there's no direct function available to do this? Please keep in mind I want to add the crop marks to existing cards, so I'm not making cards from scratch. I'm not sure but this might be called "imposition".
2. Can it be done easily via a desktop application?

Answer 1

try with latex

create file foobar-crop.tex

\documentclass{article}
\usepackage{pdfpages}
\usepackage[paperwidth=9cm,paperheight=5cm]{geometry}
\usepackage[cam,a4,center,pdftex]{crop}

\begin{document}

\includepdf[pages=-]{foobar.pdf}

\end{document}

compiling with

$ pdflatex foobar-crop.tex

will get you foobar-crop.pdf.

from: http://www.thbimage.com/pdf/adding_crop_marks_to_pdf_pan_2008_10_08_21_47_33_lutrina_.html