What is Steganography? When I first heard the word, I had no idea what it meant or that it would play such a crucial role in creating secret messages through images, pieces of literature or through audio files. According to Microsoft Copilot, Steganography can be defined as a strategic way to conceal information by encrypting messages in images, texts and or audio files. Secret information is able to be hidden within an image by modifying the least significant bit or (LSB) of the values of an image’s pixels. To understand this better, think of any type of image. Let’s think of a static-like square for example (refer to image). When the LSB of the pixel values are edited, you are able to embed another image or message within the original image (in this case, a statue). The middle image is to demonstrate how the hidden image begins to be encoded and the left image shows the final result when the statue is concealed behind the image of the static-like square .
So what are the steps of how to hide a message using steganography? The first thing to do is encryption. This step is to ensure that the secret message won’t be able to be seen even if someone tries to decode it. This is done through creating a secret key and using symmetric key algorithms. Next, it is important to embed the message. In this step, an LBS steganography tool is used to replace the LSB of the pixels from the message . After embedding the message, your final image will contain your secret message. The last step is knowing how to decode the hidden image. This is done using an LBS steganography tool that allows you to decode the message from the modified image using the secret key that was created when the image was first encrypted.
Original Prompt:
“How can steganography be used to hide text in an image by modifying the least significant bit”
Full Text Returned by Copilot:
Steganography is the art of concealing information within other seemingly innocuous data, such as images, audio files, or text. One common technique in steganography involves hiding text within an image by modifying the least significant bit (LSB) of the image’s pixel values.
Here’s how it works:
- LSB-Steganography:
- In this method, we embed a secret message inside an image by replacing the least significant bit of each pixel with the corresponding bits of the message we want to hide.
- The least significant bit (LSB) is the rightmost bit in a binary number. For example, in the binary number 10010010, the “0” is the least significant bit.
- By modifying only the first rightmost bit of an image, we can insert our secret message without significantly altering the appearance of the picture.
- However, if our message is too large, the method will start modifying the second rightmost bit and so on. An attacker might notice these changes if they analyze the image closely.
- Steps to Hide a Message in an Image:
- Encryption: Before hiding our secret message, we encrypt it to ensure that even if someone extracts the message from the image, they won’t be able to read it.
- Create a secret key (e.g., using a text editor).
- Encrypt the message using symmetric key algorithms (e.g., gpg).
- Embedding the Message:
- Obtain an image in which you want to hide your message.
- Use an LSB-Steganography tool to replace the least significant bit of each pixel with the corresponding bits of your encrypted message.
- The resulting image will contain your hidden message.
- Decoding the Hidden Message:
- Provide the recipient with the image.
- To decode the hidden data, use the same LSB-Steganography tool.
- Extract the message from the modified image.
- Decrypt the extracted message using the secret key.
About 50% of this blog post was aided by Microsoft Copilot.