[Savannah-hackers] savannah.gnu.org: submission of Spleen

[eric . rannaud]

A package was submitted to savannah.gnu.org.
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RANNAUD Eric <address@hidden> described the package as follows:
License: gpl
Other License: 
Package: Spleen
System name: spleen
This package does NOT want to apply for inclusion in the GNU project

My project, called SPLEEN, is, in a nutshell, a software which is able to put 
information into pictures.
More exactly, it modifies pixels\' RGB channels, in such a way that, sending 
the file to another one, he will be able to pick up the content.
The more interesting features are discretion and secrecy. Indeed, in order to 
extract the information, you need the original picture. SPLEEN compares the 
modified picture to the original one to find information.
The picture files produced are completely standard files, it is completely 
impossible (or at least far from easy) to guess that this particular picture is 
SPLEEN-made.
In fact, SPLEEN modifies the picture, but it is not visible to the naked eye. 
To a maximum, it modifies one of the RGB channel by less than 2.0 % and 
considering the three channels: less than 7.5E-4 %. And if you want to use a 
program to detect it, there is no reason for a picture to be a bit more (e.g.) 
darker. If you have not the original picture, and if this one is complex (like 
a photograph), I cannot see how you would be able to identify it.
So, it\'s just a standard picture file travelling over the internet. Moreover, 
without the original picture, in the same way you were not able to guess that 
the picture has been modified, you cannot extract content. I see no way of 
infering the original picture using the modified one.
In a word, the original picture plays the same role than a crypto-key in a 
symmetric algorithm.
Since SPLEEN may not be considered as a cryptographic software, it may not be 
exposed to the law in the USA restricting exportation. Anyway, I leave in 
France, where these rules don\'t apply.
For a higher security level, you can use both GnuPG and SPLEEN.
For now, I have already made the most part of the program. But, it has been 
initially made with OCaml, which is a good language but not broadly diffused. 
So, in order to make SPLEEN more easy to compile and use, I am rewritting it in 
C and Gtk+ concerning the GUI. I have not already released sources, because it 
is hard to compile on another machine than mine. The C version will doubtless 
resolve that.
It is possible to include binary files, since all is coded with Base64 before 
being included (support of exotic alphabets may be added quite easily).
Considering use of both Base64 and zlib, you may be able to include about the 
same amount of data that the size of the picture file (depending on the ability 
to compress the data).
The GUI allows user to add or remove items just as with an email-reader-agent 
when you attach files. It is also possible to edit text-items like 
email-messages.
I will probably add a GUI-less version, which could be usefull for some purpose.

If you need any other information, be sure you can contact me.