GSOC idea: Shotwell RAW developer integration

[Camilo Polymeris <cpolymeris gmail com>]

Hello Shotwell users and developers,

I have been using Shotwell for a while now. This, plus rawstudio and
the GIMP compose my main photo workflow. The interaction between
Shotwell and rawstudio is problematic, though, because the photo
databases are separate. Shotwell gets confused when you delete
pictures from within rawstudio, duplicate jpegs show up if you export
from rawstudio, RAWs and jpegs are unlinked, etc.
A few months ago I suggested a way to better integrate RAW development
software like UFraw, rawstudio, raw therapee, and many others into
Shotwell. In the mailing list thread[1] I described a solution very
similar to what I gather is planned from reading Feature Request #3061
("improve interaction with external RAW editors")[2].
This consists of --before calling the external developer software--
watching for changes to a "*_developed.jpeg" file, and passing this
filename in the commandline, or similar. UFraw has had the capability
to export to a set file for a while, using the --output command line
option, and my patch to add that feature to rawstudio (called "client
mode")[3] was accepted a while ago.
Now, the Shotwell side is still missing. I played around with
implementing it during last (austral) summer, not completing it,
because I could not afford to spend too much time on it. Still, it
helped get an idea of the dimensions of the problem. I understand, in
the meanwhile, improvements of RAW handling have been made, which
--due to that segfault that prevents me from running the latest
version-- I haven't tested yet .
My idea would be to develop this missing piece during this year's
Google Summer of Code[4], maybe under the umbrella of Gnome. I have
successfully taken part in this program during the past 2 years. I
think the scope of this project is about right for the 12 weeks of
GSoC.
I would first focus on rawstudio and UFraw integration, and if time
permits, add others later. If necessary, like I did with rawstudio,
patches can be submitted to those projects, too.
Any comments or suggestions are very welcome.

Looking forward to contributing back to the project,

Camilo

[1] http://lists.yorba.org/pipermail/shotwell/2012-June/004067.html
[2] http://redmine.yorba.org/issues/3061
[3] http://bugzilla.rawstudio.org/show_bug.cgi?id=556
[4] http://www.google-melange.com/gsoc/homepage/google/gsoc2013