Hi,
One interesting thing to do with stegangraphy is the ability to determine the contents of the hidden message by doing a hash of the original picture
compared to the processed picture. If the hash is different and the two pictures are of the same size, you've got proof that the image has been altered. It is advised to only steganographically process an image a single time and to have that original image originate from the person using the
stego software so that you can delete the original such that a comparison of the original to the modified cannot be preformed.

--- Mystic BBS v1.12 A39 2018/04/21 (Linux/64)
* Origin: Sp00knet Master Hub [PHATstar] (700:100/0)

Re: Cracking Steganography
By: warmfuzzy to All on Fri Jun 08 2018 13:38:14

Hi,
One interesting thing to do with stegangraphy is the ability to determine the contents of the hidden message by doing a hash of the original picture compared to the processed picture. If the hash is different and the two pictures are of the same size, you've got proof that the image has been altered. It is advised to only steganographically process an image a single time and to have that original image originate from the person using the stego software so that you can delete the original such that a comparison of the original to the modified cannot be preformed.

Another best practice is also to include the strenography adapted picture within a group of other
pictures that have not been altered in any way. Then use some out of band communication method to inform
the intended recipient which picture to process.

8-)

Or so I am told 8-)


Regards..Geo
ooooOOOOoooo
--- SBBSecho 3.04-Linux
* Origin: The Dungeon BBS Canberra, Australia. (3:712/620)

Steganopgrahy isn't _only_ the practice of altering the encoding of a digital image in order to embed non-visual data within it; it can also be the act of arranging the subject of the image to encode information for the viewer. It needn't even be an image.

When Jeremiah Denton blinked TORTURE in morse code he was engaging in steganography; one could discuss the particular details of a purchase order, and those details could double as revealing information for something else altogether; or one could print a comic where the stippled colours also encode binary information in their dots. And so on.

-Dan

--- Mystic BBS v1.12 A39 2018/04/21 (Raspberry Pi/32)
* Origin: Alcoholiday / Est. 1995 / alco.bbs.io (700:100/3)