Slashdot Mirror


Study Finds Low Use Of Steganography On Internet

schnippy writes: "New Scientist reports on new study from the University of Michigan that argues that steganography (the science of obfuscating communications) is not in wide use, or at least not on the 2 million images they scanned on eBay. Earlier this year, USA Today reported that Bin Laden was using steganography to disguise his communications. Full study is available here. Wonder how long before someone sets up a distributed computing client to help search for Bin Laden's secret communications? :p" Niels Provos' research was mentioned in Slashback not long ago, and this article is based on the same research.

2 of 291 comments (clear)

  1. Re:It's not always so easy to detect! by MadCow42 · · Score: 4, Informative

    I don't agree with you, actually...

    If binary "1"s are encoded as "different than original image, and 0's are "same as original image", you could change the pixel value by +/- 1 to suit the general area of the image.

    If you look closely at any scanned or digitally captured image, there's always a "noise factor", from sensor gain, etc. A value change of 1 would not be detectable due to a noise level of at least 1 pixel value.

    You could also triple your data density by encoding the R, G, and B channels separately. This could potentially be a little more noticable, but not by much. You could also encode them in different orders (rgbrgb... rrrrggggbbbb, whatever order you want) to further encrypt it.

    The only images that do not have noise are digitally created images (i.e. rendered, or drawn in a computer). Just JPEG compressing an image causes noise of more than 1 value.

    I could write a program to encrypt/decrypt like this in less than 5 minutes... the only problem I can see is distributing the "key images", which would be susceptible to being intercepted. You could always distribute them on a hard medium (CD), and trust that noone is a spy in your group. I'd probably distribute a few hundered "refrence images".

    MadCow.

    --
    I used to have a sig, but I set it free and it never came back.
  2. Jihad != terrorism by yerricde · · Score: 4, Informative

    if I was conducting a Jihad, I wouldn't trust the internet either.

    Jihad is not terrorism. In fact, the Qur'an prohibits terrorism against innocent civilians. Islam is a religion of peace, and jihad does not refer to a "holy war" but merely "struggle ... such as an internal struggle to follow Islam, a struggle against oppression, or a struggle for peace" (source:).

    --
    Will I retire or break 10K?