Two Step Encryption

Introduction

Applying Steganography followed by Visual Cryptography. Implementation based on the research paper titled "Combine use of Steganography and Visual Cryptography for Secured Data hiding in Computer Forensics"

Steganography is the method of hiding secret data inside any form of digital media. The main idea behind steganography is to hide the existence of a data in any medium like audio, video, image etc.

Visual cryptography is a cryptographic technique which allows visual information (pictures, text, etc.) to be encrypted in such a way that the decrypted information appears as a visual image.

Architecture

Project

Structure

.
├── images
├── main.py
├── README.md
├── Reference_paper.pdf
├── requirements.txt
└── src
    ├── lsb_stegno.py
    └── n_share.py

File description

File	Description
lsb_stegno.py	Methods to Encode and Decode data using LSB Steganography
n_share.py	Methods to Split and Compress LSB Encoded images

Algorithms

Steganography

Encoding data in image

# Putting modified pixels in the new image
newimg.putpixel((x, y), pixel)
if (x == w - 1):
    x = 0
    y += 1
else:
    x += 1

Decoding data from image

# string of binary data
binstr = ''

for i in pixels[:8]:
    if (i % 2 == 0):
        binstr += '0'
    else:
        binstr += '1'

data += chr(int(binstr, 2))
if (pixels[-1] % 2 != 0):
    return data

Visual Cryptography

Generating shares

# Split image based on random factor
n = int(np.random.randint(data[i, j, k] + 1))
img1[i, j, k] = n
img2[i, j, k] = data[i, j, k] - n

Compressing shares

img[i, j, k] = img1[i, j, k] + img2[i, j, k]

Usage

Setup

Install dependencies

pip install -r requirements.txt

Run using python

streamlit run main.py