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XnViewMP is a free software to view, organise, convert graphics and photos files or to create slide show, contact sheet, HTML pages.

FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor. It has a nice array of features that include image viewing, management, comparison, red-eye removal, emailing, resizing, cropping and color adjustments. Its innovative but intuitive full-screen mode provides quick access to EXIF information, thumbnail browser and major functionalities via hidden toolbars that pop up when your mouse touches the four edges of the screen. Other features include a high quality magnifier and a musical slideshow with 150+ transitional effects and more. »

digiKam is an advanced digital photo management application for linux/KDE, which makes importing and organizing digital photos a "snap". The photos are organized in albums which can be sorted chronologically, by folder layout or by custom collections.

Shotwell is an open source photo organizer designed for the GNOME desktop environment.

JPEGView is a small and fast viewer/editor for JPEG, BMP, PNG, GIF and TIFF images. On-the-fly image processing is provided - allowing to adjust typical parameters as sharpness, color balance, contrast and local under-/overexposure.

Geeqie is a lightweight Gtk+ based image viewer for Unix like operating systems. It was forked from GQview. The development is focused on features for photo collection maintenance: raw format, Exif/IPTC/XMP metadata and integration with programs like UFraw, ImageMagick, Gimp, gPhoto or ExifTool.

Gwenview is an image viewer for KDE. It can load and save all image formats supported by KDE, but Gwenview can also browse GIMP files (*.xcf). Gwenview does not try to replace your favorite image editor, so it only features the most simple image manipulations: rotation and mirroring, but can be extended by installing KIPI plugins. When working with JPEG files, Gwenview performs lossless manipulations.

Imagine is an Image & Animation Viewer for Windows with screen capture function.

Zoner Photo Studio is a feature-rich image viewer and image organizer software. It also features many editing functions including 16 bits per color channel. It is one of the first image organizers with support for GPS and 3D technologies and aims to be a universal "all-in-one" solution for the whole process of managing and processing digital photos, including acquiring, editing, archiving, and publishing them.

Eye of GNOME is the official image viewer for the GNOME Desktop environment. With it, you can view single image files, as well as large image collections. The Eye of GNOME supports a variety of image file formats. The GdkPixbuf library determines which file formats Eye of GNOME can load and save. If the appropriate plugins are installed on your system, Image Viewer will be able to open more image formats than those listed below.