iSteg is a steganography encryption/decryption tool. Basically it means that you can hide a ZIP file or a .txt file in a jpeg picture and protect it with a password. iSteg is a frontend for outguess 0.2.
Just tried it out (ver. 1.6.2) and it works as advertised (on OS 10.6.8). Was able to read the decrypted output text file. One thing I did was make sure that I deleted the source text file input bar before changing to decoding as that looked like it could otherwise potentially be a problem.
Also like the fact that documentation comes with the application and is accessible directly via the GUI. Two thumbs up for this, Developer.
One slight improvement would be for the application to accept jpeg files with the ".jpeg" extension (as is only accepts files with the ".jpg" extension) -- a very small issue, to be sure.
FTR, it appears that the MU description has a typo: the developer's site says it is a front end for Outguess 2.0 (not 0.2).
I went through the process to imbed a short message into a jpg photo and produced an output jpg file which I was able to open and all looked great. When I decoded it I produced a '.txt' file but was not able to open it I received the message " The document “output.txt” could not be opened. The file isn’t in the correct format. The file might be corrupted, truncated, or in an unexpected format. "
Any idea what I am doing wrong?
This is a nice, straightforward application that correctly encoded and decoded a short (2736 bytes) Objective C source file I had lying around into a rather large (2.7 MB) .jpg.
However, the .jpg side is a bit problematic. It apparently dropped the Profile that was embedded in the original jpg, changed the dpi from 180 to 72, dropped a number of other JFIF bits and bobs that I don't care about very much, and increased the file size (to 2.9 MB), while also introducing a small colour shift visible to the eye. Except for the colour shift, the output jpg appeared visually identical to the input jpg.
It would be nice if it could re-attach the original Profile to the new .jpg, and maintain the dpi and any other "important" tags. I don't know whether this would cure the colour shift.
I'd guess the file size is harder to maintain; I don't know much about the jpeg spec and common practice, and am not sure whether the original compression specs are recoverable from the input jpg. If they can be recovered, it would be nice if they were re-applied. I imagine the file size increase is at least partly due to the difference in compression specs.
Given an understanding of the limitations, this appears to be a pretty useful application.
iSteg is a frontend for outguess 0.2. The ZIP file is not appended to the JPEG picture but it is encrypted using the "free" bits of the jpeg file. The result is a picture file looking like the original one but containing a hidden file. This is steganography. To append file you can use the "cat" shell command, you don't need iSteg or outguess.
To see what happens to your ZIP encrypted file please see:
http://www.outguess.org/
Thanks
version 1.6.1 is now available and it is now possible to encrypt a ZIP file into a picture. When decrypting the extension ".zip" must be added if the original file was a ZIP file.
That's very good news. But it seems that iSteg can only hide a zip archive within a JPEG that's large enough in file size, i.e. a 1 MB zip archive will not go into a JPEG that's only 400 kB, which is logical though. But there's the possibility to simply append an archive to a JPEG, steganography on its most basic level. It's easy to do it in the Terminal with the cat command, but there are other ways too, I believe, including password protecting the output file.
if you append a file to a jpeg picture then you can't open the jpeg in a picture viewer! try it. The result of iSteg is a JPEG picture. You can use it for web sites, emails, everything. It's a picture. But it contains hidden data which are NOT pictures.
This is "security through obscurity".
I already tried it, and it does work with the cat command. Here's a link to a JPEG (106 kB), with an appended zip-Archive (422 kB), totaling 524 kB:
http://www.mediafire.com/?21n7p5xoson1dni
The JPEG opens in Apple's Preview, Safari, Photoshop, GraphicConverter, QuickTime Player etc., and it can be directly expanded using software like keka.
Simply open keka an drag the JPEG (containing the appended invisible zip) onto keka's Dock icon. It will unzip directly on my computer. I think it's also possible to decompress it in Terminal, e.g. unzip output.jpg
Is too bad that the developer dropped the project, it was a really nice app and it worked great in the past.
Now with snow leopard it gives me some problems :S
Simple basic interface, should work a treat, but it stalled with my first attempt, possibly because the text file I wanted to encrypt was too long. I'm not sure.
A Readme describing the options and limitations of the app with explanations of any cryptic alerts would be a big help.
I'll keep trying, this could be a useful program.
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iSteg is a steganography encryption/decryption tool. Basically it means that you can hide a ZIP file or a .txt file in a jpeg picture and protect it with a password. iSteg is a frontend for outguess 0.2.
+38
bbw7 reviewed on 06 May 2012
Also like the fact that documentation comes with the application and is accessible directly via the GUI. Two thumbs up for this, Developer.
One slight improvement would be for the application to accept jpeg files with the ".jpeg" extension (as is only accepts files with the ".jpg" extension) -- a very small issue, to be sure.
FTR, it appears that the MU description has a typo: the developer's site says it is a front end for Outguess 2.0 (not 0.2).
scharchris reviewed on 12 Apr 2011
Any idea what I am doing wrong?
+18
However, the .jpg side is a bit problematic. It apparently dropped the Profile that was embedded in the original jpg, changed the dpi from 180 to 72, dropped a number of other JFIF bits and bobs that I don't care about very much, and increased the file size (to 2.9 MB), while also introducing a small colour shift visible to the eye. Except for the colour shift, the output jpg appeared visually identical to the input jpg.
It would be nice if it could re-attach the original Profile to the new .jpg, and maintain the dpi and any other "important" tags. I don't know whether this would cure the colour shift.
I'd guess the file size is harder to maintain; I don't know much about the jpeg spec and common practice, and am not sure whether the original compression specs are recoverable from the input jpg. If they can be recovered, it would be nice if they were re-applied. I imagine the file size increase is at least partly due to the difference in compression specs.
Given an understanding of the limitations, this appears to be a pretty useful application.
+44
Michael Haeusler reviewed on 06 Nov 2010
+1
To see what happens to your ZIP encrypted file please see:
http://www.outguess.org/
Thanks
+44
+2
+44
This is "security through obscurity".
+44
http://www.mediafire.com/?21n7p5xoson1dni
The JPEG opens in Apple's Preview, Safari, Photoshop, GraphicConverter, QuickTime Player etc., and it can be directly expanded using software like keka.
How do you do it?
+44
+1
+47
Now with snow leopard it gives me some problems :S
+2
A Readme describing the options and limitations of the app with explanations of any cryptic alerts would be a big help.
I'll keep trying, this could be a useful program.