1. XnView
XnView
2. GQview
GQview, an image browser that features single click access to view images and move around the directory tree.
3. QIV - Quick Image Viewer
QIV, is a very small and pretty fast gdk/Imlib image viewer.
4. CompuPic
CompuPic for Linux is a Linux-version of the popular Windows graphic and multimedia manager.
5. KuickShow
KuickShow is an image browser/viewer with a nice filebrowser to select images to be shown, slideshow support and the ability to display the following image formats: jpg, gif, tiff, png, bmp, psd, xpm, xbm, pbm and eim. Images can be displayed either in their own window, as large as the image, or fullscreen (which shrinks images too large to display). KuickShow also has a slideshow mode.
6. GTK See
GTK See is a simple image viewer based on GTK+ 1.2.x and running on X Window System. The appearance and interface are similar to popular image viewer ACDSee, that is where the name "GTK See" come from.
7. xv
The xv program displays images in the GIF, JPEG, TIFF, PBM, PGM, PPM, X11 bitmap, Utah Raster Toolkit RLE, PDS/VICAR, Sun Rasterfile, BMP, PCX, PNG, IRIS RGB, XPM, Targa, XWD, possibly PostScript, and PM formats on workstations and terminals running the X11 Window System.
8. Imgv
Imgv is a unique and feature rich Image Viewer. It is released as free software with full source code. Imgv is portable and can run on Windows, Linux, BSD, OSX, and other operating systems.
9. Gwenview
Gwenview is a fast and easy to use image viewer for KDE. For more information, have a look at the overview.
10. Gliv
GLiv is an OpenGL image viewer, image loading is done via Gdk-pixbuf bundled with GTK+-2.6, rendering with OpenGL and the graphical user interface uses GTK+ with GtkGLExt. GLiv is very fast and smooth at rotating, panning and zooming if you have an OpenGL accelerated graphics board. It supports thumbnails and navigating through them using two images menus and a browser.
11. ShowImg
ShowImg is a feature-rich image viewer which can display numerous formats, including JPEG, PNG, GIF (animated), MNG, PSD, ... It consists of a tree view frame, a directory/preview frame, and a view frame. The (larger) view frame can be exchanged with the (smaller) directory/preview frame. It can preview and display images from multiple directories and search for identical images. ShowImg also features a full-screen mode, zooming, sorting, drag'n'drop with Konqueror, support for images in compressed archives (tar, tar.gz, zip, ...) and kipi plugins.
12. fbi
fbi. This is a image viewer for Linux framebuffer devices. It has PhotoCD, jpeg, ppm, gif, tiff, xwd, bmp, and png support built-in. Unknown formats are piped through convert (ImageMagick), which hopefully can handle it.
13. gThumb
gThumb is an image viewer and browser for the GNOME Desktop. It also includes an importer tool for transferring photos from cameras.
14. Electric Eyes
The ee package contains the Electric Eyes image viewer for the GNOME desktop environment. Electric Eyes is primary an image viewer, but it also allows many types of image manipulations. Electric Eyes can handle almost any type of image.
15. Eye of Gnome
The Eye of GNOME image viewer is the official image viewer for the GNOME Desktop environment. With it, you can view single image files, as well as large image collections.
16. GImageView
GImageView is a yet another image viewer which solves hopless situation under displaying a lot of images. It works on X Window System.
Hugues Image Viewer is an image viewing and image analysis application. It supports any pixel type (from binary to 64 bit, integer or floating point), 3D, multi-spectral, and multi-component documents and images. It includes image viewing functions such as zooming, cropping, and rotating.