Steganogrphy✍🏻💻

Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video. It has existed for a long time, and nowadays, digital steganography is used to hide data inside images. We can hide all kinds of data by using different digital steganographic methods.

Video Steganogrpahy📽

A digital image is a representation of pixel values, and every pixel value will have numbers containing information regarding the pixel. A digital color image will have red, green, and blue channels and eight bits to represent each channel, so every channel can take a value from 0-255, and this value represents the intensity of the pixel.

(R, G, B)=(0,0,0)

This is the representation of the color black and this represents the color white.

(R, G, B)=(255,255,255) 

Take an array of pixels as an example and suppose we want to hide the character A in it. This is how we will do it:

(R, G, B)= (11101010 11101001 11001010),(10111001,11001011,11101000),(11001001 00100100 11101001)

This is a pixel array, and we want to hide A in it. The ASCII value of A is 65. If we convert it to binary, we get 01000001. So if we use LSB transformation, we can change the LSB of all the numbers in our array and get:

(R,G, B)= (11101010 11101001 11001010),(10111000,11001010,11101000),(11001000 00100101 11101001)

Image Steganography🖼

Image steganography can be simply done using the stegano package in python.

• First we will import lsb

from stegano import lsb

• To hide a text in an image named file.png

secret =  lsb.hide("file.png", "text")

• To save the encoded image in a file named e_file.png

secret.save("e_file.png")

• To decode the secret from the file e_file.png

lsb.reveal("e_file.png")

Video Steganography

As we know video is a collection of frames, where each frame is a picture. So in this script, the frames were extracted from the video along with the audio and the hidden message is embedded in these frames and then they are stitched together and saved into another file named "Embedded_Video.mp4". So to decode the hidden message we would use the "Embedded_Video.mp4" file and the script would extract the broken strings from each frame and then join the extracted strings in a list to form a message.

Packages Used

• stegano
• cv2
• numpy
• time
• math
• os
• shutil
• ffmpeg
• subprocess

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