Batch conversion of images using ImageMagic

Today I needed to convert multiple .pdf files into .tiff images with specific DPI and LZW compression. I found it’s very simple using ImageMagic.
[bash]
# install
sudo apt-get install imagemagick

# convert .pdf to lzw compressed .tiff changing dpi to 300
mkdir tiffs
for f in *.pdf; do
echo `date` $f;
convert -density 300 -compress lzw $f tiffs/$f.tiff;
done
date
[/bash]

For more options, have a look at ImageMagic site.

Save PDF with CMYK color encoding

Most printing services require CMYK color encoding, which is not natively supported by Inkscape. Because of that, you will need some third-party solution.

Firstly, I have tried Inkscpae extension, ExportPDFCMYK, but unfortunately it turned out not working in my setting (Ubuntu 14.04).

But then, I have came across ghostscript-based solution, that works great! Simply export your project into PDF in Inkscape and then execute:
[bash]
f=poster.pdf
gs -dSAFER -dBATCH -dNOPAUSE -dNOCACHE -sDEVICE=pdfwrite
-sColorConversionStrategy=CMYK -dProcessColorModel=/DeviceCMYK
-sOutputFile=${f%????}_cmyk.pdf $f
[/bash]

Inspired by zeroset.