Ubuntu installs a number of applications for graphic manipulation and viewing.
The GIMP is a bitmap-based graphics editor styled along the lines of Adobe Photoshop™. The GIMP provides powerful tools such as layering, image scaling, filters and more, for creating and editing professional looking graphic images. Experiment, be creative, don't be afraid to make mistakes, virtually every action can be undone. You can also scan images directly into The GIMP using XSane Image Scanning Program. To get help on virtually anything in The GIMP including the menus, just press the F1 key.
gThumb is an image viewer and browser written for the GNOME environment. It can handle many different formats, including JPEG, PNG, and GIF. As well, it can display GIF animations. gThumb not only lets you view image files, but also has many other features which allow you to add comments to images, organize images in catalogs, print images, view slide shows, set your desktop background, and more.
The Image Viewer application enables you to view single image files, as well as large image collections.
Image Viewer has a variety of features to help you view your images. You can zoom in and out, or view the image full screen. You can also rotate and flip the image. The collection view allows the viewing and editing of large image collections. In this view, image operations can be applied to all selected images at once.
The PostScript viewer provides you with a simple interface to display PostScript files. PostScript is a language for encoding printed documents and can be interpreted by PostScript enabled printers. PostScript files are created using PostScript compliant printer drivers. They are cross platform and can be opened and displayed using software capable of interpreting the PostScript language.