Secure Data Hiding In Images Using Steganography

A simple Python-based steganography project that hides a secret message and passcode in an image using Least-Significant-Bit (LSB) encoding, and later retrieves the message securely.

Overview

This project uses robust LSB steganography to embed a secret message along with a passcode into an image.Steganography is the technique of concealing data or information within a carrier medium, such as an image, audio, or video, so that the hidden message is not detectable to the human eye or ear.

Key Concepts:

Steganography vs Cryptography:

Cryptography encrypts the data, making it unreadable to unauthorized parties but does not hide the fact that data is being sent.

Steganography, on the other hand, hides the existence of the message itself, making it ideal for scenarios where confidentiality needs to be maintained without drawing attention.

Image as a Carrier Medium: Images are commonly used as the carrier medium for steganography. By modifying the pixel values in a way that is not visible to the human eye, we can embed data without altering the image’s appearance significantly.

Security in Steganography:

Confidentiality: The hidden data should be encrypted before embedding in the image to avoid unauthorized access in case the image is intercepted.

Imperceptibility: The hidden data should not be noticeable in the image. To achieve this, the data is embedded in the least significant bits (LSB) of the image pixels.

Capacity: The amount of data that can be hidden within the image is important. This capacity should be balanced with imperceptibility and security.

Features

• Encryption: Embeds a secret message and passcode into mypic.jpg and saves the result as encrypted.png.

• Decryption: Retrieves the hidden message from encrypted.png when the correct passcode is provided.

• User-Friendly GUI: Easy-to-use interfaces for both encryption and decryption processes.

• Robust Data Storage: Uses a header to store the lengths of the passcode and message for accurate extraction.

Requirements

• Python 3.x

• NumPy

• OpenCV

• VS code

Installation

• Clone the repository.

• Install the required libraries:pip install opencv-python numpy

Place an image mypic.jpg in project directory

Advantages of Using Steganography in Images:

1. Security

2. Stealth

3. Versatility

PROJECT EXECUTION

Step 1: Install Python

1. Go to the official Python download page: https://www.python.org/downloads/
2. Click on the "Download Now" button for the latest version of Python.
3. Follow the installation instructions to install Python on your computer.

Step 2: Install VS Code

1. Go to the official VS Code download page: https://code.visualstudio.com/download
2. Click on the "Download" button for the latest version of VS Code.
3. Follow the installation instructions to install VS Code on your computer.

Step 3: Install OpenCV

1. Open VS Code.
2. Open the terminal in VS Code by pressing `Ctrl + `` (backtick) or by navigating to "View" > "Terminal".
3. Type the following command to install OpenCV using pip: pip install opencv-python
4. Press Enter to run the command.

Step 4: Create a New File

1. In VS Code, click on "File" > "New File" or press Ctrl + N.
2. Save the file with a .py extension (e.g., steganography.py).

Step 5: Copy and Paste the Code

1. Copy the following Steganography code:

import cv2

import os

import string

#Read the image

img = cv2.imread("mypic.jpg")

#Get the secret message and password from the user

msg = input("Enter secret message: ")

password = input("Enter a passcode: ")

#Create dictionaries for character-to-ASCII and ASCII-to-character mappings

d = {}

c = {}

for i in range(255):

d[chr(i)] = i

c[i] = chr(i)

#Initialize variables for embedding the message

m = 0

n = 0

z = 0

#Embed the message into the image

for i in range(len(msg)):

img[n, m, z] = d[msg[i]]

n = n + 1

m = m + 1

z = (z + 1) % 3

#Save the encrypted image

cv2.imwrite("encryptedImage.jpg", img)

#Open the encrypted image

os.system("start encryptedImage.jpg")

#Get the passcode for decryption

pas = input("Enter passcode for Decryption: ")

#Decrypt the message if the passcode is correct

if password == pas:

message = ""

n = 0

m = 0

z = 0

for i in range(len(msg)):

message = message + c[img[n, m, z]]

n = n + 1

m = m + 1

z = (z + 1) % 3

print("Decryption message: ", message)

else:

print("YOU ARE NOT authorized")

2. Paste the code into the steganography.py file.

Step 6: Run the Code

1. Make sure you have an image file named mypic.jpg in the same directory as the steganography.py file.
2. Open the terminal in VS Code by pressing `Ctrl + `` (backtick) or by navigating to "View" > "Terminal".
3. Type the following command to run the code: python steganography.py
4. Press Enter to run the command.

That's it! The code should now run and prompt you to enter a secret message and passcode. then it generates the Encrypted image known as Steganography.