Hi,
I would like to merge four pdf files as a 2x2 grid. Is there any software available that can help with such a problem?
Thank you very much,
Diamantis

Google for "merging pdf files" and possibly add "linux" and you shall find what you are looking for.

u can try---

pdf2ps file1.pdf file1.ps
pdf2ps file2.pdf file2.ps
cat file1.ps file2.ps > file12.ps
ps2pdf file12.ps file12.pdf

OR
using convert , directly from the ImageMagick toolkit. You probably already have this one installed on your favourite Linux distribution; if not, almost every known Linux distribution has a package for it. Even if you don't need to edit PDF files you should have it, it is a wonderful swiss army knife for command line image processing. The syntax for merging PDF files is simple:

convert file1.pdf file2.pdf file3.pdf out.pdf

[See the man page of convert ]

It's easy to turn 4 pdf pages into a 4x1, but 2x2 is a different matter. swagata paul's convert solution led me to look at the manpage of ImageMagick, which has a montage option and deals with pdfs. Check it out.

edit - montage is actually a program in the ImageMagick suite.

Thank you for your suggestions, but the problem is that with imagemagick I loose resolution, that is why I am looking for software that works directly on pdf or ps files.
Thanks

I dunno but this might help:
http://www.accesspdf.com/pdftk/