Darktable is a virtual lighttable and darkroom for photographers.
It manages your digital negatives in a database and lets you view them
through a zoomable lighttable.  It also enables you to develop raw images
and enhance them.  This project tries to fill the gap between the many
excellent existing free raw converters and image management tools (such
as ufraw or f-spot).

The Darktable project strongly recommends that you should build and run
darktable on x86_64 if possible.  The i686 build will not give you a
satisfactory user experience.  As an absolute minimum, your processor
must support SSE2 instructions (i.e. Pentium 4 or higher, or Athlon 64
or higher).

The following are optional dependencies:

GraphicsMagick - for importing a wide range of non-RAW image formats
libwebp        - for exporting images in WebP format
flickcurl      - for exporting images to Flickr
json-glib      - for exporting images to Facebook
colord         - for colour profile management
colord-gtk     - for colour profile management
osm-gps-map    - for map georeferencing

If you have nVidia or AMD/ATI graphics with more than 1Gb of memory,
either nvidia-driver or amd-app-sdk is an optional runtime dependency.
Darktable will then detect and use the OpenCL capability of your graphics
hardware for faster processing.  See the Darktable User Manual, Chapter
7 Section 2, for more details (in particular, be sure to read it if you
have AMD/ATI graphics).