Shotwell a nice photo organizer for Gnome and Ubuntu
Shotwell is a new digital photo organizer for the GNOME desktop. Shotwell imports photos from digital cameras and automatically organizes them into events based on the time they were taken. Shotwell includes a non-destructive photo editor, allowing you to crop, rotate, and adjust the color and contrast of any photo instantly. Auto-enhance can improve a photo with a single click. Edited photos may be exported in any size, ready for sharing.
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