Steganography Algorithm and Testing

One of the challenges of steganography is to make the hidden data undetectable by statistical tests that analyze the frequency or intensity of colors in an image. 🕵️‍♂️

One possible algorithm that can achieve this goal is based on the Steghide program, which is a steganography tool that can hide data in various kinds of image- and audio-files.

Algorithm Steps

  1. Create a cover image file that contains the original image file as a sub-image. The cover image file has a higher resolution and quality than the original image file, and it also has some random noise added to it.
  2. Embed the hidden data into the cover image file using a simple substitution cipher. The hidden data consists of a series of bits (0 or 1) that correspond to different colors in the original image file.
  3. Convert the cover image file into an ASCII text format using a simple mapping scheme. Each color value in the cover image file corresponds to one byte (8 bits) in ASCII text.
  4. Compress the ASCII text format using a simple lossless compression algorithm. The compression algorithm reduces the size of each byte by removing any redundant or unnecessary information from it.
  5. Encrypt the compressed ASCII text format using a simple symmetric encryption algorithm. The encryption algorithm uses a secret key that only knows how to decrypt and encrypt messages using this algorithm.
  6. Attach an additional header and footer to the encrypted ASCII text format using a simple format string. The header and footer contain some metadata about the cover image file and its embedded data.

The result is an encrypted ASCII text format that looks like any other normal text message when viewed on any device or platform. However, anyone who knows how to decrypt and decompress it can recover the hidden data from it.

Testing the Algorithm

To test whether this algorithm makes a hyperlink undetectable by color-frequency based statistical tests inside an image, we need to do some experiments:

  1. Create some cover images and some hidden data files for testing purposes.
  2. Use Steghide or any other steganography tool that supports our chosen method to embed our hidden data into our cover images.
  3. Convert our cover images into binary files using Steghide or any other tool that supports our chosen method.
  4. Apply some color-frequency based statistical tests on our binary files using any tool that supports our chosen method.
  5. Compare the results of our statistical tests with those of some known methods for hiding data in images.

Analyzing the Image

To analyze this image, we can use some online tools that can perform different steganalysis methods, such as layer analysis, zsteg, steghide, outguess, exiftool, binwalk, foremost, and strings.

These tools can reveal anomalies or patterns that indicate the presence of hidden data in the image.

After performing these steps, compare the results of the different tools and see if there is any hidden data in the image. If there is, try to extract it. If there is not, the image is clean and does not contain any hidden data.