Although Ubuntu (and all its variants for that matter) come bundled with an image viewer, you don't have to make do with the default application for viewing and managing images and photos. Plenty of other tools can do the job better and more efficiently. The trick is to pick the one that fits your exact needs, and this article covers several image viewing applications that are worth considering.

PhotoQt for Photos

If you're primarily interested in viewing and showing photos, then the aptly named PhotoQt application [1] is exactly what you need. PhotoQt is not the most sophisticated image viewer out there, but its blend of simplicity and flexibility makes it a handy utility, indeed. The application is designed to make the task of showing and flicking through photos as transparent as possible.

PhotoQt features a clean interface free from any distracting toolbars and menus (Figure 1). Instead the main window has three hot zones. The hot zone at the bottom of the window hides a thumbnail bar, while the hot zone in the top right side activates the General Functions menu.

Figure 1: PhotoQt features a clean and unobtrusive interface.

Besides the usual items like Open File , About , and Quit , the menu contains several useful entries. Set as Wallpaper does exactly what it says: It sets the currently viewed photo as the desktop wallpaper. Using the Slideshow command, you can configure the slideshow settings, such as time, transition duration, and music file, and then start the slideshow. To launch the slideshow directly, use Quickstart instead. Finally, the Show Details command displays a widget containing basic EXIF metadata, including shutter speed, ISO, aperture, focal length, and geographical coordinates (if available).

Want to see the exact location of the photo on the map? Click on the coordinates, and PhotoQt opens Google Maps or Bing Maps in the default browser. Instead of using Show Details , you can activate the widget by moving the mouse to the third hot zone at the left border of the window or by using the Ctrl+E keyboard shortcut.

PhotoQt is powered by the GraphicsMagick image processing system, which supports a wide range of image formats from the usual suspects like JPEG, TIFF, and PNG to more obscure formats like JNG, PPM, EPDF. Thus, PhotoQt can handle pretty much any image you throw at it. More importantly, the application is lightning fast when it generates thumbnails and displays photos.

Practically all common actions in PhotoQt (zoom in/out, show next or previous photo, open file, etc.) can be performed using keyboard shortcuts, which provide a faster and more efficient way of working with PhotoQt (Figure 2). The application lets you edit the default key bindings as well as specify custom shortcuts. To do this, choose Settings from the General Functions menu (or press E) then switch to the Shortcuts section.

Figure 2: PhotoQt provides extensive support for keyboard shortcuts, and you can define custom key bindings.

Here, you can view and modify the existing keyboard shortcuts as well as define new ones. While you are at it, you might as well adjust other settings. PhotoQt is infinitely configurable, and you can tweak almost every aspect of the app – from look and behavior to image details and information (Figure 3).

Figure 3: You can tweak a myriad of settings in PhotoQt.

PhotoQt's packages for Ubuntu are available from a PPA. Use these three simple commands:

sudo add-apt-repository ppa:samrog131/ppa
sudo apt-get update
sudo apt-get install photoqt

to install the application.

Geeqie

digiKam and other photo management applications offer a plethora of tools for organizing photos, but at times you need something lighter. For example, when you are on the move, you might want to use a no-frills tool for quickly viewing and sorting photos pulled from the camera. Or, perhaps you don't need all the features of a dedicated photo management application, and you want to replace it with a more lightweight solution altogether. Enter Geeqie [2], a fast and nimble image viewer that has a few clever tricks up its sleeve.

Serious photographers and shutterbugs alike will be pleased to learn that Geeqie supports RAW files out of the box, courtesy of the UFRaw software. This means that you can preview and manage RAW files without resorting to an external tool. Better yet, Geeqie can batch convert RAW files to the JPEG format, which can be done by selecting the RAW files you want and choosing Edit | UFRaw Batch . Because Geeqie doesn't allow you to adjust any settings, it won't replace a proper RAW processing application. However, the RAW processing functionality can come in handy for quick-and-dirty RAW conversion.

When viewing photos, you can enable the Image Overlay feature (Image | Image Overlay ), which displays key information about the photo, such as basic EXIF data and histogram (Figure 4). Using the View | Exif Window command (or the Ctrl+E keyboard shortcut), you can bring up the Metadata window, which lets you view all EXIF data of the current photo.

Figure 4: Geeqie in action.

Geeqie also sports a so-called Pan View (View | Pan View or Ctrl+J), which presents photos as a timeline, a calendar, or a folder hierarchy (Figure 5). Like any image viewer worth its salt, Geeqie sports a slideshow feature and basic sorting capabilities.

Figure 5: Pan view mode can be used to view photos as a timeline.

Geeqie also offers the nifty Marks tool designed to make it easier to sort and filter photos. Using this feature, you can assign up to six marks to each photo using the appropriate commands from the Select menu (Figure 6). Alternatively, you can enable the Marks view (Select | Show Marks ), and use the mouse to tick the appropriate check boxes next to each photo. You can then use the Select | Mark x | Filter mark command to display all photos containing a specific mark or marks.

Figure 6: The Marks tool lets you rate photos.

Similar to Photo, Geeqie provides extensive support for keyboard shortcuts, which gives you a faster and more efficient way to work with photos. Geeqie is available in the official Ubuntu software repositories, so you can install it on your machine through the Software Center.

gThumb

gThumb [3] may look like yet another image viewer, but behind its unassuming appearance hides a rather capable application that can help you to keep tabs on your images and media files with consummate ease (Figure 7).

Figure 7: gThumb in all its beauty.

The application features several creature comforts that make it easier to view and manage images. The bookmarks functionality, for example, can save time when navigating to often-used folders. To add a bookmark, select the desired folder and choose Bookmarks | Add Bookmark (or use the Ctrl+D keyboard shortcut). This creates a bookmark in the Bookmarks menu.

Filters is another handy feature that can be used to show only images matching specific criteria. Say you want to view only photos tagged with tokyo . Choose View | Filter , select Images from the drop-down list, and press the New button to create a filter. In the Edit Filter dialog, give the filter a name, and specify a rule as shown in Figure 8. Press Save to save the filter and close the Filters window. Enable the filterbar by choosing View | Filterbar , then pick the created filter from the filter list in the filterbar.

Figure 8: Specifying a filter in gThumb.

Although the filtering functionality can be useful for showing a subset of images on-the-fly, the Catalog feature lets you create permanent collections. Catalogs in gThumb act as virtual folders (i.e., photos added to a catalog remain in their original folders). Using this feature, you can keep photos from different folders in one catalog.

For example, if you have photos taken in Berlin in different folders on your hard disk, you can group them all into a Berlin catalog. To do this, right-click on the Catalogs entry in the navigation pane, choose Create Catalog , give the new catalog a name, and press Create .

You have two ways to add photos to the catalog. The easiest one is to simply drag and drop selected photos into the catalog. Alternatively, you can right-click on a photo and select Add to Catalog in the context menu. Instead of creating catalogs and adding photos to them by hand, you can use the Organize feature to do the job for you. This nifty tool can automatically organize photos in the current folder into catalogs based on specific criteria.

To organize, for example, all photos containing the travel tag into a Travel catalog, press the Organize button in the upper-right corner of gThumb's window (Figure 9).

Figure 9: Using the Organize tool.

Select the Tags item from the Group file by drop-down list, enable the Include sub-folders option if you want the tool to process sub-folders, and press Execute . Next, enable the travel tag and press Save . This process automatically creates the Tags | travel catalog with all the matching photos in it.

If you use tags to keep tabs on your photos, you'll appreciate gThumb's tag editing feature. To quickly assign one of the existing tags to a specific photo, right-click on it and choose the desired tag from the Tags menu. Choose the Other item to add new tags and assign them to the photo.

gThumb lets you modify additional metadata, too. To do this, press the Comment button on the main toolbar to open the Metadata dialog.

The application also features a handful of basic editing tools (Figure 10). To access them, double-click on a photo to open it, then press the Edit file button in the top-right corner of the editing interface. Although gThumb won't replace a dedicated image editing application, the available tools can come in handy for quickly tweaking basic settings like brightness, saturation, and contrast as well as adjusting white balance and fixing common problems.

Figure 10: gThumb features basic editing tools.

When it comes to sharing photos, the Share button in the main menu lets you upload photos to several popular photo-sharing services, including Flickr, Picasa Web, and Photobucket. Additionally, you can use the Web Album command to generate static HTML-based photo albums.

gThumb is available in the official Ubuntu repositories, so you can install it via the Software Center or by running the sudo apt-get install gthumb command.

Final Word

Each of the image viewers covered here have their own advantages and drawbacks. PhotoQt is a perfect tool for showcasing photos, and as such, it lacks any features for organizing and editing images. Geeqie can handle RAW files, which makes it a great choice for photographers who shoot in RAW. And, gThumb offers several powerful tools for keeping tabs on a large number of photos.

The good news is that you don't have to choose between these three applications. Install them all on your machine and use each of them for the tasks they handle best.