$ gtk-image-selector -h

usage: gtk-image-selector [-h] [-n] [-m DEFAULT_IMAGE] [-f FILE]
                          [-d DIRECTORY] [-p POSITION] [-r PREVIEW_SIZE] [-s]
                          [-i ICON] [-w WINDOW_TITLE] [-o OK_LABEL]
                          [-c CANCEL_LABEL] [-t FILTER_LABEL] [-l SIZE_LABEL]
                          [--dump-config]

A Gtk Image Chooser with Preview

optional arguments:
  -h, --help            show this help message and exit
  -n, --no-config       do not attempt to read any config file; just use the
                        command line parameters
  -m DEFAULT_IMAGE, --default-image DEFAULT_IMAGE
                        the image to display when no preview is available
                        (proposed size: 512x521)
  -f FILE, --file FILE  default file to select
  -d DIRECTORY, --directory DIRECTORY
                        default directory to show
  -p POSITION, --position POSITION
                        set window position, either as X,Y of "center"
  -r PREVIEW_SIZE, --preview-size PREVIEW_SIZE
                        set preview image size (100-1000)
  -s, --show-scale      show scale widget (hidden by default)
  -i ICON, --icon ICON  set window icon
  -w WINDOW_TITLE, --window_title WINDOW_TITLE
                        set window title
  -o OK_LABEL, --ok-label OK_LABEL
                        set OK button label
  -c CANCEL_LABEL, --cancel-label CANCEL_LABEL
                        set Cancel button label
  -t FILTER_LABEL, --filter-label FILTER_LABEL
                        set filter field label
  -l SIZE_LABEL, --size-label SIZE_LABEL
                        set size field label
  --dump-config         print a sample config file (can be saved to /etc/gtk-
                        image-selector.conf or ~/.config/gtk-image-
                        selector/config)

./gtk-image-selector -m no-preview.png

$ gtk-image-selector --dump-config

# the default folder to browse
folder =

# the default size of the image preview
preview_size = 256

# the image to show when no image file is selected
# or when the selected image is broken
# please make sure this image actually exists
default_image = /usr/share/icons/Adwaita/512x512/mimetypes/image-x-generic.png

# the icon to use as a window icon
icon = /usr/share/icons/Adwaita/16x16/mimetypes/image-x-generic.png

# set this to True to display the image scaling widget
show_scale = False

# window title and labels
window_title = Select an Image
ok_label = _Select
cancel_label = _Cancel
filter_label = Images
size_label = Size: