Shotwell is a digital photo organizer designed for the GNOME desktop environment. It allows you to import photos from disk or camera, organize them in various ways, view them in full-window or fullscreen mode, and export them to share with others.
Features
1.Three ways to import photos:
* Drag-and-drop: Simply drag photos from your file manager and drop them onto the Shotwell window. You may drag files or directories. The photos will be imported into your library. By default, photos are copied to your library directory (the Pictures directory in your home directory). If you hold down Ctrl+Shift while dragging photos in, Shotwell will import the photos without copying them.
* Camera: Connect your digital camera to your computer. Shotwell will detect it and list it in the sidebar. When you select the camera, Shotwell will load previews of each photo. You may choose specific photos to import or to import them all.
* File menu: Choose File ▸ Import From Folder… and select a directory from the chooser dialog box.
2.Shotwell automatically groups photos taken at the same time. You can also use tags to organize your photo collection.
3.You can rotate, crop, reduce red-eye, and adjust the exposure, saturation, tint, and temperature of each photo.
4.Shotwell is able to share photos over the Internet services Facebook, Flickr, and Picasa Web Albums, all of which require an account, which is free.

Install Shotwell
Shotwell runs on Linux and (with limited features) on Windows.For Ubuntu Karmic Koala (9.10) and Lucid Lynx (10.04),open terminal from Applications->Accessories->terminal and type this three commands:

sudo add-apt-repository ppa:yorba/ppa
sudo apt-get update
sudo apt-get install shotwell

For older version and other systems,see:http://www.yorba.org/shotwell/install/

Once installed, Shotwell is available in your Applications menu under Graphics or Photography. Shotwell may also be executed automatically when a camera is plugged in to your computer.

Homepage:http://www.yorba.org/shotwell/

User guide:http://ubuntuguide.net/wp-admin/post-new.php
Pictures(from Shotwell sourcepage)
photos_collection

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