Welcome to XDA

Search to go directly to your device's forum

Register an account

Unlock full posting privileges

Ask a question

No registration required
Post Reply

[APP] StegDroid Alpha v 0.75

OP fredley

10th January 2011, 05:52 PM   |  #1  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
Hi guys/gals

I'm working on this app for my final year dissertation. It performs Echo Steganography on wave files. My app uses this to encode short text messages in an audio file, then share it. I've just got the Steg side of things working, so I wanted to get some early feedback on whether it works for other people (and if it's awfully slow - it uses a lot of Fourier Transforms etc...).

This is very early days, so the app isn't anything like ready for primetime yet, but the basics are in place. I'd really appreciate it if you could download it and:

* Have a go at embedding some text in a recording and seeing if it correctly extracts it again.
* Run the tests available in the menu
* Email me one of your recordings (tfmw2 [at] cam [dot] ac [dot] uk) to see if I can extract the data on my phone.
* Supports encryption with a shared key
* Transcodes audio files to ogg format for sharing

Updates (0.75)

* Added Multicasting of messages to contact groups

* Fixed bug with sharing files in paranoid mode
* Better memory management, should work more reliably with longer messages
* Reduced error rate (less garbled messages)
* Reduced file size by 33%
* Other bug fixes

Any problems let me know!



Cheers
Attached Files
File Type: apk StegDroid0.75.apk - [Click for QR Code] (534.2 KB, 162 views)
Last edited by fredley; 28th March 2011 at 04:33 PM.
The Following 2 Users Say Thank You to fredley For This Useful Post: [ View ]
11th January 2011, 03:23 AM   |  #2  
tridge's Avatar
Senior Member
Flag Michigan
Thanks Meter: 10
 
121 posts
Join Date:Joined: Jan 2009
Donate to Me
More
I'm not sure what this does =\
11th January 2011, 12:40 PM   |  #3  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
The app records a file from the microphone and embeds a secret message into it. You can send that file to someone, and if they've got the same app they can extract the secret message from the audio file. Anyone listening to the audio file wouldn't be able to tell that it's got a message hidden in it, as the difference is hard to distinguish with the human ear.
The Following User Says Thank You to fredley For This Useful Post: [ View ]
11th January 2011, 04:21 PM   |  #4  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
I've uploaded a new version, it's a bit more stable and a bit easier to use!
The Following User Says Thank You to fredley For This Useful Post: [ View ]
00Ghz
11th January 2011, 05:27 PM   |  #5  
Guest
Thanks Meter: 0
 
n/a posts
Interesting, maybe we can team up this will be an interesting feature for my project
11th January 2011, 07:36 PM   |  #6  
Meltus's Avatar
Senior Member
Flag Manchester
Thanks Meter: 1,015
 
1,911 posts
Join Date:Joined: Jan 2009
Donate to Me
More
Works pretty well, cool idea too!
I was able to make it fail though by using a long jumble of letters (I screenshotted before and after to compare) but it still only got about 5 wrong (little diamond with a ? In the middle).
Nice work!

Sent from my Nexus One using XDA App
The Following User Says Thank You to Meltus For This Useful Post: [ View ]
11th January 2011, 07:43 PM   |  #7  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
Thanks Meltus

Could you let me know the length of the string. Were the wrong characters at the end or distributed throughout? What kind of audio input were you testing with (voice message, background noise, music etc.)?
The Following User Says Thank You to fredley For This Useful Post: [ View ]
11th January 2011, 11:29 PM   |  #8  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
Update

Now supports basic crypto. Run tests from the menu before you start to check the crypto test passes (if it doesn't, let me know!).
12th January 2011, 03:03 AM   |  #9  
Meltus's Avatar
Senior Member
Flag Manchester
Thanks Meter: 1,015
 
1,911 posts
Join Date:Joined: Jan 2009
Donate to Me
More
Quote:
Originally Posted by fredley

Thanks Meltus

Could you let me know the length of the string. Were the wrong characters at the end or distributed throughout? What kind of audio input were you testing with (voice message, background noise, music etc.)?

Length of the string was about 30 characters, the wrong characters were distributed and were just regular letters.
As for the audio it was just me tapping on the mic for about 20 secs.

I've been doing more tests too and it only seems to occur when you have a few repeating characters. I typed out the keyboard lines and it got it correct, until i started repeating every other character a few times, then it started to get a few wrong.
12th January 2011, 12:35 PM   |  #10  
fredley's Avatar
OP Retired Recognized Developer
Flag Cambridge
Thanks Meter: 5
 
48 posts
Join Date:Joined: Apr 2009
Quote:
Originally Posted by Meltus

Length of the string was about 30 characters, the wrong characters were distributed and were just regular letters.
As for the audio it was just me tapping on the mic for about 20 secs.

I've been doing more tests too and it only seems to occur when you have a few repeating characters. I typed out the keyboard lines and it got it correct, until i started repeating every other character a few times, then it started to get a few wrong.

That's strange! The embedding works bit-by-bit, rather than byte-by-byte, so it's very strange that repeated chars should cause an issue. I'll look into it though. Did you try the same test with continuous sound, such as music? I'll see if I can replicate it here. What hardware/android version are you using?

Post Reply Subscribe to Thread
Previous Thread Next Thread
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes