convert serveral image files to a single djvu file

Assuming you are on Linux. Install the djvulibre packages (in Debian/Ubuntu djvulibre-bin), cd to the path where you have your images and run the following:

for x in *.jpg; do c44 -dpi 300 $x; done
djvm -c ../result.djvu *.djvu
ddjvu -format=pdf myfile.djvu myfile.pdf

Source: http://www.vitki.net/book/page/converting-jpeg-scans-or-djvu-files-pdf Another useful source: http://commons.wikimedia.org/wiki/Help:Creating_a_DjVu_file

On Windows you can either use cygwin and follow these steps or use any of the several available GUI tools. The latter option won't give you the same speed though, as it can't be scripted.

For color pages:

pages=pg1.djvu
c44 -dpi 300 pg1.jpg pg1.djvu

For black/white:

for (( i = 2; i <= $N; i++ )); do
  echo $i
  convert pg$i.jpg pg$i.pbm
  cjb2 pg$i.pbm pg$i.djvu
  pages="$pages pg$i.djvu"
done

Join all pages:

djvm -c book.djvu  $pages