Steganography

Steganography is the technique of hiding secret data within an ordinary, non-secret, file or message in order to avoid detection the secret data is then extracted at its destination.The word steganography is derived from the Greek words steganos (meaning hidden or covered) and the Greek root graph(meaning to write). This is just basic encryption for hiding text messages inside simple images but obviously, this algorithm has its own limitations.

✔️ How to get started

• Clone the repo with git clone in git bash

git clone https://github.com/Shadow129-sys/Steganography.git

• move to "steganography" folder

cd Steganography

• install all the required lib using pip from requirements.txt

pip install -r requirements.txt

• run main.py by

For Windows environment: python -u main.py
For Linux environment: python3 main.py

then enter the mode encrypt or decrypt, in encrypt mode we need to enter the coverfile name with extension but that file should be in the same directory, the program will take the message from input.txt and creates a encrypted file encrypted.png now just to test the program we can delete the cover file and input.txt and then run the decrypt mode in this mode we need to enter the encrypted filename with extension encrypted.png it will generate an output file output.txt with the decrypted text.

e - encryption
d - decryption
Choice : e
processing started.....
coverfile : "Your regular image as filename.ext"
Encrypted file created...
process ended...

this will be printed if the program can encrypt the file or else it will show an error, in decrypt mode an output.txt file will be created with the decrypted text.

e - encryption
d - decryption
Choice : d
processing started.....
encrypted file : "Your encrypted image as filename.ext"
Decrypted Text : "your decrypted text here"

process ended...

💡 How it works

We all know that a coloured image has 3 channels in 1 pixel in BGR format, we used binary of ascii value in 8 bits to store the value of a letter, This algorithm store the number of words and number of letters in each word in green channel and the value of each character in red channel in it's binary form.

⛔ Limitations

• As of now this algorithm can only take 250 words or less than that
• It can't encrypt very large word in the encrypted image
• The ascii code for the letter should be from 0 to 255
• Only works for coloured images
• The program is not actually changing the image's metadata so if someone wish to send the encrypted image then send it as a document file, so that the file can retain its encrypted bits

❓ What's next

We can use some basic cryptography methords like substitution cipher, caesar cipher or Vigenere cipher to encrypt the message and then pass the encrypted message to this algorithm, in this way we can achive double encryption, this will make the encryption more harder to crack.