Loupe

Loupe is the official GNOME image viewer, shipped as part of GNOME Core since GNOME 45, replacing the long-serving Eye of GNOME (eog). It is written entirely in Rust using GTK4 and libadwaita, bringing GPU-accelerated rendering and a modern adaptive interface to everyday image browsing. What sets Loupe apart architecturally is its use of the glycin library, which decodes each image format in a separate sandboxed process — meaning a maliciously crafted image file cannot compromise the host application or the user's session.

Features

• Sandboxed image decoding — The glycin library runs each image decoder in an isolated subprocess, preventing malicious image files from escaping into the viewer process.
• GPU-accelerated rendering — GTK4's scene graph renders images on the GPU, enabling smooth zoom and pan even on large files.
• SVG support with tiled rendering — Scalable vector graphics are rendered at native resolution using tiled rendering to handle arbitrarily large SVGs without exhausting memory.
• EXIF-aware rotation — Rotating a JPEG writes the new orientation to the file's EXIF metadata rather than re-encoding pixel data, preserving quality.
• Print layout dialog — A dedicated print dialog lets you set paper size, margins, and image scaling before sending to a printer.
• Touch and trackpad gestures — Pinch-to-zoom and swipe-to-navigate work naturally on touchscreens and precision touchpads.
• High-DPI aware — Images are displayed at the correct physical size on HiDPI screens without blurring.
• Adaptive layout — The UI adapts to narrow windows and mobile form factors, consistent with libadwaita design conventions.
• Wide format support — JPEG, PNG, WebP, AVIF, HEIC, GIF, TIFF, BMP, SVG, and more via the glycin loader ecosystem.
• GNOME Core — Loupe is installed on every standard GNOME desktop; no separate installation is needed on GNOME-based systems.

Installation

On most GNOME-based desktops Loupe is already present. If you need to install or update it:

# Flatpak — Flathub (recommended for latest version)
flatpak install flathub org.gnome.Loupe

# Fedora (included in GNOME spin by default)
sudo dnf install loupe

# Debian 13 (Trixie) / Ubuntu 24.10+
sudo apt install loupe

# Arch Linux
sudo pacman -S loupe

# Nix
nix-env -iA nixpkgs.loupe

Usage

Loupe registers itself as the default image viewer on GNOME, so double-clicking any image in Files (Nautilus) opens it automatically. You can also launch it from the terminal:

# Open a single image
loupe photo.jpg

# Open multiple images — navigate between them with arrow keys
loupe *.png

# Open from a directory — all images in the directory become navigable
loupe ~/Pictures/holiday/IMG_0001.jpg

Keyboard shortcuts

Viewing image properties

Click the ⓘ button in the header bar to open the Properties panel. It shows file size, dimensions, colour profile, camera make and model, exposure settings, and GPS coordinates (with a map link) when EXIF data is present.

glycin: Sandboxed image loading

The glycin library is the security foundation that distinguishes Loupe from most image viewers. Traditional viewers load image data directly in the application process; a heap overflow in a JPEG decoder, for example, could give an attacker control of the viewer process and access to the user's files.

Glycin addresses this by forking a separate, sandboxed loader process for each image. The loader process:

• Runs under a restrictive seccomp-bpf syscall filter
• Has no network access
• Can only read the specific file it was asked to decode
• Communicates results back to Loupe over a private D-Bus socket

If the loader crashes or is exploited, the damage is contained to that short-lived process. This architecture also means adding a new image format only requires writing a new loader — the viewer itself needs no changes.

Loupe vs Eye of GNOME