# Ubuntu – Is it possible to preview arbitrary formats in Nautilus

file formatnautiluspreviewsthumbnails

I recently found out that Nautilus (Ubuntu 12.04 at least) can show thumbnails of files of non-image formats, for example (data grapher) grace files (.agr) shows a small version of the graph contained in its data. Obviously, there some library or script that is processing the file, making the image, and allowing nautilus to show a small version of it.

This made me think that in principle any file that potentially can be processed into an image can serve as a Nautilus thumbnail.

For example, a .tex file (which can be converted to .pdf) or a gnuplot script can be displayed as a thumbnail when possible.

In the case of .tex file, the correspoding .pdf can be created by the command pdflatex file.tex.

The question is, how can I tell Nautilus to create a thumbnail for an arbitrary format and how do I specify the commands to do so within Nautilus?

Update 2014,

I still didn't manage to preview anything with the answer posted, I created this script in /usr/bin/tex-thumbnailer:

pdflatex $1 convert -density 300${1%.*}.pdf -resize 25% \$2


and a file /usr/share/thumbnailers/tex.thumbnailer:

[Thumbnailer Entry]
TryExec=tex-thumbnailer
Exec=tex-thumbnailer %u %o
MimeType=text/x-tex;


I can't make nautilus to generate/show the preview even for simple TeX files. I don't know what I am doing wrong.

• Here's the documentation on how to add a new thumbnailer.

You need to add two keys on gconf:

• /desktop/gnome/thumbnailers/application@x-foo/enable (boolean)
• /desktop/gnome/thumbnailers/application@x-foo/command (string)

Where application@x-foo is the MimeType for the kind of file you want to generate the thumbnails. Set enable to True and command to the command to create the thumbnail.

gconftool-2 --set /desktop/gnome/thumbnailers/application@x-foo/enable --type bool true
gconftool-2 --set /desktop/gnome/thumbnailers/application@x-foo/command --type string "application-x-foo-thumbnailer %i %o %s"


The folders are created automatically. %i is the input file, %o where to write the output file (png) and %s the size of the thumbnail.

And here's how to add a MimeType for custom files.

I found another way which seems easier, you can create a file in /usr/share/thumbnailers/ for example foo.thumbnailer:

[Thumbnailer Entry]
TryExec=/usr/bin/application-x-foo-thumbnailer
Exec=/usr/bin/application-x-foo-thumbnailer %i %o %s
MimeType=application/x-foo;


You can separate several MimeTypes with ;.