Steganography (A Data Hiding Technique)

Posted by : mangesh_more Friday, April 12, 2013

This technique is used for secure communication as cryptography but It is different from cryptography in various manner as described below :

Steganography hides text in plain sight, while cryptography scrambles plaintext (original message) into ciphertext (coded message)
Even though a message is hidden, you should always encrypt it as well (my opinion, anyway)
You can easily hide messages in digital images with the most basic software out there (Hex editors, MS Paint, etc)
Other media types lend themselves to Steganography too. Messages can be hidden in audio/video files, or even plain text!

Basically there are many methods to implement Steganography but here I am going to show you two methods which are very basic and easy to get back.

Method 1 :

In this method we will use simple command prompt to implement Steganography.

Step 1 : Select any image and write your message in to any text editor and save it with the image.
Here I am selecting image img.jpg and my text file is message.txt and in this file the message is “Hey This is a secret message”.

Step 2 : Now open command prompt and navigate to the directory where both image file and txt file are and then type a simple command to merge both files.

copy /B img.jpg + message.txt new.jpg

and now a new image file named as new.jpg will create.

Now when you will open this image file it will look same as our previous image file but when you will open this with notepad then at last you will find you message.

you can merge any file with images file by this command. For example if you merge a rar/compressed file with this image file then when you will open your output file with image viewer then it will show an image and when you will open that output file with winrar or any similar software then it will show you the content of rar file.

Method 2: You can also use a tool named as MP3Stego which is used to hide your message into an mp3 file.

First download is from here.

Go to command prompt and type following command to hide your message into the mp3 file.

encode -E hidden_text.txt -P pass audio_file.wav done.mp3

It will compress audio_file.wav (mono, 44.1 kHz, 16bit encoded) and hides hidden_text.txt. The hidden text is encrypted using pass as a password. This produces the output called done.mp3.

Use the following command to get the hidden message (file) from the mp3

decode -X -P pass done.mp3

it will uncompress done.mp3 into done.mp3.pcm and attempts to extract hidden information. The hidden message is decrypted, uncompressed and saved into done.mp3.txt.

Note: Here hidden_text.txt is a file which contains your secret message. Audio_file.wav is a audio file which will contains our secret message in it. Done.mp3 file is a output file which is a combination of our secret message and the audio_file.wav.

Method 3: You can use a tool named as edjpgcom which is used for adding a comment in a image file.

Download this from here.

1: Copy the image in folder where you have extracted this tool.

2: Now open command prompt and type

Edjpgcom.exe filename.jpeg

You will get a new window here like this one :