GitHub - archistico/ShadeOfColor2: A simple cross-platform tool to hide files inside PNG images

2 min read Original article ↗

🌈 ShadeOfColor

Turn any file into an image, and back again.
A simple cross-platform tool to hide files inside PNG images.

✨ What is ShadeOfColor?

Have you ever wanted to:

  • 📧 Send a file by email that the provider does not allow?
  • ☁️ Store restricted file types on cloud services that only accept images?
  • 🕵️ Add an extra layer of privacy when sharing files publicly?
  • ✒ Are you a journalist in a totalitarian state and need to release a file?
  • 🔒 Exfiltrate data into systems that monitor suspicious files?

With ShadeOfColor, you can convert any file into an image (-crypt) and later recover the original file (-decrypt).
The output looks like a normal PNG, but it actually carries your data inside its pixels.

Process
screenshot-file

🖥️ Screenshot

FileToImage
screenshot-file

ImageToImage
screenshot-image

🚀 Features

  • 🔄 Two-way conversion:

    • -crypt: transform a file into a PNG image.
    • -decrypt: restore the original file from the PNG.

  • 📝 Embedded metadata:

    • Signature "ER"
    • Original file size
    • Original filename
    • SHA1 hash for integrity check

  • 🖼️ Cross-platform: uses SixLabors.ImageSharp. Works on Windows, Linux, macOS.

  • ✅ Integrity check: ensures the file is not corrupted or tampered with.

📦 Usage

Install

Install-package SixLabors.ImageSharp

Encrypt a file into an image

With executable (download release)

./ShadeOfColor2.exe -crypt myfile.exe output.png

Alternative

dotnet run -crypt FileToImage.cs out.png

Decrypt an image back into the original file

With executable (download release)

./ShadeOfColor2.exe -decrypt output.png

Alternative

dotnet run -decrypt out.png

🔒 Future Improvements

AES encryption of the input file before embedding.

Support for multiple encryption algorithms and user-defined keys.

Command -info to quickly display metadata without extracting the file.

Steganographic modes (make the output image look more “natural”).

⚠️ Disclaimer

ShadeOfColor is a tool for privacy and experimentation. It is not intended to be used for illegal purposes. Please respect the terms of service of the platforms where you use it.

❤️ Contribute

Ideas, issues, and pull requests are welcome! Help us make ShadeOfColor even more powerful and versatile.

📜 License

MIT License – feel free to use, modify, and share.