Ubuntu – How to enable thumbnails for flac files in Nautilus

There is a way of getting this done explained in the Floorplanner Tech Blog. To compile dump-gnash on a fresh Maverick you'll need

sudo apt-get install gcc libboost-dev libboost-thread-dev libagg-dev libsdl1.2-dev libcairo-dev libgstreamer0.10-dev libatk1.0-dev libglib2.0-dev libpango1.0-dev libgtk2.0-dev libgtkglext1-dev libgl1-mesa-dev libgif-dev libjpeg-dev libgstreamer-plugins-base0.10-dev libspeex-dev libcurl-dev

And then you just follow the steps. This will take a long time.
NOTE: For Step 7 use the following script instead:

if [[ $3 ]]; then
    raw="$(mktemp)"
    dump-gnash $2 -P "FlashVars=url=file://$1" -D "$raw" --max-advances 1 -j 500 -k 500
    tail -c 1MB "$raw" | convert -size 500x500 -depth 8 rgba:- -separate -swap 0,2 -combine -trim png:"$3"
    trap "rm $raw" EXIT
else
    echo "Insufficient arguments (expected 3 arguments)"
    exit 1
fi

Once you have the final script running you just hook it into gconf-editor

gconftool-2 -s "/desktop/gnome/thumbnailers/application@swf" -t string "/usr/bin/swfthumbnailer.sh %s %i %o"
gconftool-2 -s "/desktop/gnome/thumbnailers/application@swf/enable" -t boolean 'true'
gconftool-2 -s "/desktop/gnome/thumbnailers/application@x-swf" -t string "/usr/bin/swfthumbnailer.sh %s %i %o"
gconftool-2 -s "/desktop/gnome/thumbnailers/application@x-swf/enable" -t boolean 'true'
gconftool-2 -s "/desktop/gnome/thumbnailers/application@x-shockwave-flash/command" -t string "/usr/bin/swfthumbnailer.sh %s %i %o"
gconftool-2 -s "/desktop/gnome/thumbnailers/application@x-shockwave-flash/enable" -t boolean 'true'

Then restart (or restart gnome-settings-daemon), and you've got swf thumbs!

P.S.: This is a huge hack. A better way to do this would be vastly appreciated.

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.

To add one with gconftool-2:

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 ;.