Steganography/stego analysis

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The easiest way to recognize whether a graphic is suspect is to compare it with the original. It is not difficult, thanks to Google image search, we can see this by checking the identification of processing. Then we can compare both photos using the compare tool (available in the imagemagick package - the effect in the gallery section.

For the computer, the differences can be seen on the palm of your hand, although the tools are trying to be imperceptible by the human eye.

Okay, we already know that a photo can potentially have hidden information, now that we need to extract the information we need to get to know the way it insert.

under construcion

Further complications[edit]

Detecting a probable steganographic charge is often only part of the problem, because the load can be encrypted first. Encrypting the load is not always done only to hinder the recovery of the load. Most strong ciphers have the desirable property that the load appears indistinguishable from the scattered noise evenly, which can make stegoanalizations extremely difficult.


Gallery[edit]

For example, I used impressionistic graphics, the file that was hidden in it is lorem ipsum. In the last example (outguess) it contained enough information that I had to insert only one sentence with lorem ipsum out of necessity.

Below you can see fragments of the image that have changed in relation to the original:

The LSB technique ([StegoShare):
Stegoshare-compare.jpg
graphs (steghide)
Steghide-compare.jpg
Outgusses:
Outguess-compare.jpg