Hiding secret data into image and audio files (OpenSuSe)

Steghide is a steganography program that is able to hide data in various kinds of image and audio files. The color-frequencies (for image files) or sample-frequencies (for audio files) are not changed, thus making the embedding resistant against first-order statistical tests.

Features include:
    * Compression of embedded data
    * Encryption of embedded data
    * Embedding of a checksum to verify the integrity of the extraced data
    * Support for JPEG, BMP, WAV and AU files

Installation:
You should have the following packages (libraries) installed to use steghide. (you can get all these lib from software.opensuse.org) Mhash, MCrypt, libjpeg, zlib

Download the rpm file for Steghide
Install this rpm file using command: # rpm -ivh steghide-0.5.1-1.i386.rpm

The basic usage is as follows: Go to command prompt and use following commands

$ steghide embed -cf image.jpeg -ef file.txt
Enter passphrase:
Re-Enter passphrase:
embedding "file.txt" in "image.jpeg"... done

This command will embed the file file.txt in the cover file image.jpeg.

After you have embedded your secret data as shown above you can send the file image.jpeg to the person who should receive the secret message. The receiver has to use steghide in the following way:

$ teghide extract -sf image.jpeg
Enter passphrase:
the file "file.txt" does already exist. overwrite ? (y/n) y
wrote extracted data to "file.txt".

If the supplied passphrase is correct, the contents of the original file file.txt will be extracted from the stego file image.jpeg and saved in the current directory.

If you have received a file that contains embedded data and you want to get some information about it before extracting it, use the info command:

$ steghide info image.jpeg
"image.jpeg":
  format: jpeg
  capacity: 9.9 KB
Try to get information about embedded data ? (y/n) y
Enter passphrase:
  embedded file "file.txt":
    size: 129.0 Byte
    encrypted: rijndael-128, cbc
    compressed: yes