The following tutorial explains how to generate a contact sheet from a pdf (or from several images).

 sudo apt-get install imagemagick


The imagemagick library is a very handy tool for graphics editing (go to site). Particularly, it is useful for repeated tasks.

In this example, the pdf file contains 12 pages (see screenshot below).

With convert, the pdf is splitted into individual images.

 convert mosaic.pdf file.png
convert --help
convert mosaic.pdf -crop 842x480+0+70 file.png


Properties of the images can be seen with identify.

 identify file-0.png


And finally, the contact sheet is generated using montage.

 montage -verbose -geometry 400x400+0+0 -background '#ffffff' -fill 'gray' file*.png contact.png


If the files are not necessary, these might be removed.

 rm file*


I hope this has been useful.