The Tumbler package contains a D-Bus thumbnailing service based on the thumbnail management D-Bus specification. This is useful for generating thumbnail images of files.
Tumbler allows to load a number plugins to support different file formats. Most plugins are loaded by default, if the required libraries are provided.
sed -n 's/MimeType=//p' /usr/share/thumbnailers/gdk-pixbuf-thumbnailer.thumbnailer
oasis.opendocument (presentation, text,chart, image), sun.xml ( calc, writer, draw, impress. math) and some more..thumbnailer desktop files. Also known as customized or desktop thumbnailers. See examples below.Tumbler has since version 0.1.27 a configuration file to control the priority, locations and file sizes the plugin is used for: tumbler.rc.
To override the default configuration, located in one of the xdg directories on your system, you can copy the rc-file to your $XDG_CONFIG_HOME directory.
NB: $XDG_CONFIG_HOME defaults to ~/.config.
mkdir -p "${XDG_CONFIG_HOME:=~/.config}/tumbler"
cp /etc/xdg/tumbler/tumbler.rc "$XDG_CONFIG_HOME/tumbler/"
Each group in the configuration file is responsible for the settings of a particular thumbnailer plugin. The following keys can be used to adjust a plugin:
true and false are accepted.~/ and ~username/ are allowed. Leave empty to allow all locations.~/ and ~username/ are allowed. Leave empty to exclude nothing. Please note that paths in Excludes precede those in Locations.
As of Tumbler 4.17.0 (first stable release 4.18.0), these settings extend to external thumbnailers of the desktop-thumbnailer plugin, by adding the group “X-Tumbler Settings” to the .thumbnailer files. Further instructions and an example are given at the end of the tumbler.rc file.
By default the cover thumbnailer is disabled. The reason is that it sends information (movie title extracted from the filename) to online services to retrieve a poster. This information is normally harmless, but it is private, so therefore it's not enabled by default.
In order to use the cover thumbnailer you need to copy the tumbler.rc file to your home directory as described above and set the Disabled key to false. It is also advisable to set the Locations path to the directory where you store your movies.
[CoverThumbnailer] Disabled=false Priority=3 Locations=~/movies MaxFileSize=0 #APIKey=your-api-key-from-themoviedb.org
The movie thumbnailer supports two different movie APIs. By default, the The Open Movie Database API is used. You can also choose to use The Movie DB, but this site requires an API key which you have to request or uh… search.
The advantage of the latter is that their database has better support for internationalized movie names.
After creating the rc file, it is best to log off and on again to restart Thunar and Tumbler, because both applications cache the mime-type combinations.
As of version 0.2.0, the desktop thumbnailer functionality has been added back into tumbler. This functionality supports custom .thumbnailer files placed in the XDG_DATA_DIRS/thumbnailers directories and the XDG_DATA_HOME/thumbnailers directory (which defaults to ~/.local/share/thumbnailers). The former is the place for system wide thumbnailers (normally in /usr/share/thumbnailers), while the latter is the preferred place for the user's customized thumbnailers (see below).
Since 4.17.0 (first stable release 4.18.0), in case of several .thumbnailer files with the same name in the thumbnailer directories, the one placed in the highest priority directory override all the others.
For example, to create a custom thumbnailer for .dds files, do the following:
.thumbnailer file:[Thumbnailer Entry] Version=1.0 Encoding=UTF-8 Type=X-Thumbnailer Name=dds Thumbnailer MimeType=image/x-dds; Exec=convert -thumbnail %s %i %o
<?xml version="1.0" encoding="UTF-8"?>
<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
<mime-type type="image/x-dds">
<comment>dds file</comment>
<icon name="image"/>
<glob-deleteall/>
<glob pattern="*.dds"/>
</mime-type>
</mime-info>
…and run
update-mime-database ~/.local/share/mime
Another example are albums cover thumbnails for folders in a music collection. A custom thumbnailer can be added to e.g. add a file folder.jpg or cover.jpg into a folder and display its thumbnail instead of the default folder icon:
[Thumbnailer Entry] Version=1.0 Encoding=UTF-8 Type=X-Thumbnailer Name=Folder Thumbnailer MimeType=inode/directory; Exec=sh -c '~/bin/folder-thumbnailer "$@"' _ %s %i %o %u
In order to support different names for the picture-file and to remove the thumbnail if not needed any more (display the default folder icon), a separate script is required:
#!/bin/bash
covers=("$2"/{.,}{folder,cover}.{jpg,png})
for f in "${covers[@]}"; do
[ -f "$f" ] && {
cover=$f
break
}
done
if [ -z "$cover" ] || ! convert -thumbnail "$1" "$cover" "$3"; then
gdbus call --session --dest=org.freedesktop.thumbnails.Cache1 --object-path /org/freedesktop/thumbnails/Cache1 \
--method org.freedesktop.thumbnails.Cache1.Delete "['$4']" >/dev/null
fi
Don't forget to give execution permission to the file:
chmod u+x ~/bin/folder-thumbnailer
and to restart Thunar and Tumbler so that the new folder mime type is taken into account.
Note: ImageMagick is a required dependency for this script.
A thumbnailer for text-based documents can be created using the convert function from the ImageMagick package with the following thumbnailer file:
[Thumbnailer Entry] Version=1.0 Encoding=UTF-8 Type=X-Thumbnailer Name=Text Thumbnailer MimeType=text/plain;text/html;text/css; Exec=sh -c '~/bin/textthumb "$@"' _ %s %i %o
And supporting script:
#!/bin/bash
iFile=$(<"$2")
tempFile=$(mktemp) && {
echo "${iFile:0:1600}" > "$tempFile"
convert -size 210x290 -background white -pointsize 5 -border 10x10 -bordercolor "#CCC" caption:@"$tempFile" "$3"
rm "$tempFile"
}
You can add additional mime types to the MimeType line of the thumbnailer file to support additional text-based document types.
A thumbnailer for comic book archives (cbr, cbz, cbt, cb7) can be created using the comicthumb utility (search for it your distro's repositories). If not already present as /usr/share/thumbnailers/comicthumb.thumbnailer, create the following thumbnailer file:
[Thumbnailer Entry] TryExec=comicthumb Exec=comicthumb %u %o %s MimeType=application/x-cb7;application/x-cbr;application/x-cbt;application/x-cbz;application/x-ext-cb7; application/x-ext-cbr;application/x-ext-cbt;application/x-ext-cbz;application/vnd.comicbook-rar
Note: Make sure there is an image/webp mimetype defined in your system.
[Thumbnailer Entry] Version=1.0 Encoding=UTF-8 Type=X-Thumbnailer Name=webp Thumbnailer MimeType=image/webp; Exec=sh -c '~/bin/webpthumbs "$@"' _ %s %i %o
And supporting script:
#!/bin/bash if tempfile=$(mktemp) && /usr/bin/webpmux -get frame 1 "$2" -o "$tempfile"; then /usr/bin/convert -thumbnail "$1" "$tempfile" "$3" else /usr/bin/convert -thumbnail "$1" "$2" "$3" fi [ -f "$tempfile" ] && rm "$tempfile"
[Thumbnailer Entry] Version=1.0 Encoding=UTF-8 Type=X-Thumbnailer Name=STL Thumbnailer MimeType=model/stl; Exec=sh -c '~/bin/stl-thumbnailer "$@"' _ %i %o %s
And supporting script:
#!/bin/bash
if (($# < 3)); then
echo "$0: input_file_name output_file_name size"
exit 1
fi
INPUT_FILE=$1
OUTPUT_FILE=$2
SIZE=$3
if TEMP=$(mktemp --directory --tmpdir tumbler-stl-XXXXXX); then
cp "$INPUT_FILE" "$TEMP/source.stl"
echo 'import("source.stl", convexity=10);' > "$TEMP/thumbnail.scad"
openscad --imgsize "500,500" -o "$TEMP/thumbnail.png" "$TEMP/thumbnail.scad" 2>/dev/null
convert -thumbnail "$SIZE" "$TEMP/thumbnail.png" "$OUTPUT_FILE" &>/dev/null
rm -rf $TEMP
fi