Image steganography
&
Steghide Tool
Contents
Contents ....................................................................................................................2
Image steganography ...............................................................................................3
Steghide tool..............................................................................................................4
Introduction ............................................................................................................4
Steghide tool features .............................................................................................4
Using Steghide .......................................................................................................5
Steghide Installation and Running .........................................................................6
Verbose Mode ......................................................................................................10
Compression Mode .............................................................................................. 11
Conclusion...............................................................................................................12
References ...............................................................................................................13
Image steganography
Image steganography is a technique for hiding secret messages or data within
digital images. The hidden data can be in any form, including text, images, audio,
or video. The basic premise of image steganography is that the human eye is not
sensitive enough to detect small changes in the color or brightness of an image, so
these changes can be used to hide the secret data.
Image steganography is achieved by modifying the Least Significant Bits (LSBs)
of the pixel values in the image. The LSBs are the least significant bits of each
pixel's color value, which are the least noticeable to the human eye. By changing
the LSBs slightly, the original image can be modified to include hidden data
without being visibly altered.
There are many different methods for implementing image steganography, each
with its own advantages and disadvantages. Some techniques involve embedding
the hidden data directly into the LSBs of the image pixels, while others use more
sophisticated methods such as frequency domain transformations to hide the data.
Image steganography can be used for a variety of purposes, including covert
communication, digital watermarking, and digital rights management. However, it
can also be used for illicit purposes, such as hiding malware or other malicious
code within seemingly harmless images.
Overall, image steganography is a powerful and widely used technique for hiding
data within digital images. It is important to use this technique responsibly and in
accordance with applicable laws and regulations.
Steghide tool
Introduction
Steghide is a command-line tool for hiding data within various types of files, such
as images and audio files. The tool uses a technique called steganography to
conceal the data within the file without changing its appearance or functionality.
Steganography is a method of hiding information within a medium such as text,
images, or audio, in a way that is not easily detectable. Unlike cryptography, which
focuses on making a message unreadable to unauthorized parties, steganography is
about hiding the existence of the message itself.
Steghide encrypts the data using advanced encryption standards (AES-256) and
then embeds it within the least significant bits of the file. This process makes the
hidden data difficult to detect with the naked eye and most analysis tools.
Steghide is a popular tool for secure data storage and transmission, as it provides a
high level of protection against unauthorized access. However, it should be used
responsibly and in accordance with applicable laws and regulations. [1].
Steghide tool features
Steghide is a popular command-line tool for hiding data within various types of
files, such as images and audio files. Some of its notable features include:
• Encryption: Steghide uses AES-256 encryption to protect the hidden data,
ensuring that it cannot be read without the correct password.
• Multiple file formats: Steghide supports a wide range of file formats,
including JPEG, BMP, WAV, and AU.
• Compression: Steghide can compress the data before hiding it, which can
help to reduce the size of the resulting file.
• Configurable embedding method: Steghide provides several different
methods for embedding data within a file, each with its own advantages and
disadvantages.
• Command-line interface: Steghide is a command-line tool, which means that
it can be easily integrated into scripts and other automated processes.
• Open source: Steghide is open source software, which means that its source
code is freely available for inspection and modification.
Overall, Steghide is a versatile and powerful tool for hiding data within files, and
its encryption and compression features make it a popular choice for secure data
storage and transmission.
Using Steghide
To use Steghide tool for image steganography, we have these steps [2]:
• Install Steghide: If you haven't installed Steghide on your system, you can
do so by running the command "sudo apt-get install steghide" (for Ubuntu
and Debian-based systems) or by downloading and installing the appropriate
package for your operating system from the Steghide website.
• Prepare your data: Before you can hide your data in an image file, you need
to prepare it by converting it to a format that Steghide can use. You can do
this by using a text editor to create a text file, or by using a tool like GPG or
OpenSSL to encrypt your data.
• Choose an image file: Choose an image file that you want to use for
steganography. Steghide supports a variety of file formats, including BMP,
GIF, JPEG, and PNG.
• Hide your data: Once you have prepared your data and chosen your image
file, you can use the Steghide command-line interface to hide your data in
the image. The basic syntax for hiding data with Steghide is:
steghide embed -cf [image file] -ef [data file] -p [passphrase]
In this command, "[image file]" is the path to the image file, "[data file]" is
the path to the data file you want to hide, and "[passphrase]" is an optional
passphrase that you can use to encrypt your hidden data.
• Extract your data: To extract the hidden data from an image file, use the
following command:
steghide extract -sf [image file] -p [passphrase]
In this command, "[image file]" is the path to the steganographic image file,
and "[passphrase]" is the passphrase (if used) that was used to encrypt the
data.
Steghide Installation and Running
Update system packages
update all available repositories in the system
Install the steghide tool
Getting help in Steghide
Embedding Data in The Image
We hide data in the image using Steghide so that only the person who
acknowledges it can read that. So, we made a text file named as user.txt in which
we wrote our confidential data and image.jpeg is that file in which we are
embedding our data. To achieve this, we’ll be executing the following command:
steghide embed -ef <txt filename> -cf <media filename>
Here we use passphrase as a password to embed file in image, and this password
we will use when extracting data from image.
And we can set password in command itself, like this:
steghide embed -ef <txt filename> -cf <media filename> -p <password>
ef and cf are termed as embedded file and cover file respectively.
And the image still like:
Extraction of Data Via Steghide
Using Steghide adds an extra layer of security by allowing us to use a password for
it. Now, to extract the hidden data use the following command:
steghide extract -sf <media filename>
sf is a secret file
view file information before extracting
If we have an image that is suspected to have data hidden and if so, So we can get
some information about the file before extracting it by using the following info
option with steghide command.
Remove Steghide Tool
To remove the steghide we can use this command:
sudo apt-get remove steghide
Verbose Mode
Steghide's verbose mode is an option that allows you to see more detailed
information about the steganography process as it occurs. When verbose mode is
enabled, Steghide will display additional information in the output, such as the
percentage of the embedding process completed, the number of bytes embedded,
and any errors that occur during the process.
To enable verbose mode in Steghide, you can use the -v or --verbose option when
running the embed or extract command.
In embed: steghide embed -cf [cover file] -ef [data file] -p [passphrase] -v
In extract: steghide extract -sf [steganographic file] -p [passphrase] -v
Verbose mode can be useful when you need to monitor the progress of the
steganography process or when you need to troubleshoot any issues that may occur
during the process. However, it can also generate a large amount of output, so it is
generally not recommended to enable verbose mode unless needing the additional
information.
Compression Mode
Steghide's compression mode is an option that allows you to compress the data
before embedding it in an image file. This can be useful for reducing the size of the
data, making it easier to embed in the image file.
To enable compression mode in Steghide, you can use the -Z or --compress option
when running the embed command. For example, to enable compression mode
when embedding data in an image file, you can use the following command:
steghide embed -cf [cover file] -ef [data file] -p [passphrase] -Z
Conclusion
In conclusion, image steganography is a powerful technique for hiding data within
digital images, and it has a wide range of applications in various fields. However, it
is important to use this technique responsibly and in accordance with applicable
laws and regulations.
Steghide is a popular tool for implementing image steganography, as it provides
strong encryption and compression features, along with configurable embedding
methods. The tool is open source and available on multiple platforms, making it
accessible to a wide range of users.
Steghide can be used for various purposes, including secure data storage and
transmission, digital watermarking, and covert communication. However, it can
also be used for illicit purposes, such as hiding malware or other malicious code
within seemingly harmless images.
Overall, the use of image steganography and Steghide requires careful
consideration and responsible use to ensure that the technology is not misused or
abused.
References
[1] “Steghide - manual.”
https://steghide.sourceforge.net/documentation/manpage.php (accessed May 06,
2023).
[2] “Steghide — A beginners tutorial. Welcome. | by Ashraful Alim | System
Weakness.” https://systemweakness.com/steghide-a-beginners-tutorial-
35ec0ea90446 (accessed May 06, 2023).
