Geeqie
There are many image viewers for Linux. However, the Geeqie Image Viewer, which is based on GTK3, not only brings images to the screen quickly but also has a few special features that could make it the top choice for pragmatic users upon closer inspection.
Geeqie was likely the first Linux image viewer that could handle RAW images without a special converter, simply by reading and displaying the embedded JPEG preview image found in every RAW file.
Additionally, this lightweight program includes a simple image management system that, unlike Shotwell or the heavyweight Darktable, does not perform image imports but keeps the images in the existing folder structure. It allows for the creation of collections and provides an image search function that can also find similar images.
How to user Geeqie
By default, Geeqie displays a file manager on the left and the actual image viewer on the right. The width of both columns can be adjusted with the mouse. Additionally, both areas can be shown separately in two windows. Through the view menu, the image viewer can be configured in various ways to display up to four images side by side for comparison.
Geeqie also allows for editing the Exif data of an image. To do this, you can display another column on the right by going to View > Information Sidebar or by pressing CTRL+K, which offers even more functionality: displaying histograms, tagging images, rating them, and editing additional fields. Another sidebar (CTRL+S) is for sorting images into folders or collections.
An English-language user manual is available online in HTML or PDF formats.
Documentation
The user Manual may be found online in two formats, HTML or PDF.
Installation
Geeqie can be easily installed from the Ubuntu package source Universe, which contains community-maintained programs:
sudo apt install geeqie
Alternativen
Gnome mit Loupe, KDE mit Gwenview oder Xfce mit Ristretto bringen ihre eigenen Bildbetrachter mit, die optisch gut in den Desktop eingepasst sind. Feh ist ein immergrüner Bildbetrachter für Konsolen-Fans mit einigen unerwarteten Spezialitäten.
Gnome with Loupe, KDE with Gwenview, Xfce with Ristretto – many Linux desktops come with their own image viewer that is well-integrated into the desktop environment. Something completely different is Feh, a perennial image viewer for console fans with some surprising features.