LinuxQuestions.org - [SOLVED] Which tool for merging PDF-files?

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Quote:

Originally Posted by eXpander_ (Post 4912244)

This gives very poor quality results due to its internal conversion algorithms. To increase the quality of the output, it is better to read the input PDF files with a higher density (in dots per inch (DPI)) and then resize the output density back to common DPI, 96 for example. I usually use a input density of 600 (after many trial and errors), and then resize with 93.75% (if you dont resize you will get a huge output file).

An example:

Code:

convert -density 600 fileinput_1.pdf fileinput2_.pdf -resize 93.75% output.pdf

Have you actually tried and confirmed that you need the -density?

I am well aware of this switch when converting a .pdf to .jpg. Standard density is 50 dpi or so, not even 96 IIRC. However, when I tested this command I posted yesterday I left out the -density on purpose, and the merged file happened to be the same resolution as the originals.

This is my version in case it is relevant:

Code:

Version: ImageMagick 6.6.0-4 2010-11-16 Q16 http://www.imagemagick.org

Copyright: Copyright (C) 1999-2010 ImageMagick Studio LLC

Features: OpenMP

Besides, a density of 600 even for a single PDF usually brings your computer down on its knees.

jlinkels

Quote:

Originally Posted by jlinkels (Post 4912337)

Have you actually tried and confirmed that you need the -density?

By "Trial and Error" I really mean that I have "actually tried and confirmed" this on my own. I tried without density, but that gave me really poor results.

Quote:

Originally Posted by jlinkels (Post 4912337)

I am well aware of this switch when converting a .pdf to .jpg. Standard density is 50 dpi or so, not even 96 IIRC. However, when I tested this command I posted yesterday I left out the -density on purpose, and the merged file happened to be the same resolution as the originals.

This is about merging pdf-files, not converting them to other formats.

Quote:

Originally Posted by jlinkels (Post 4912337)

This is my version in case it is relevant:

Code:

Version: ImageMagick 6.6.0-4 2010-11-16 Q16 http://www.imagemagick.org

Copyright: Copyright (C) 1999-2010 ImageMagick Studio LLC

Features: OpenMP

I use 6.7.7_10.

Quote:

Originally Posted by jlinkels (Post 4912337)

Besides, a density of 600 even for a single PDF usually brings your computer down on its knees.

jlinkels

That's another question. I use pretty modern computers (minimum dual-cores), and it goes pretty fast (in seconds).