Advanced Browser-Based Steganography Suite via Images

StegnaVault Pro is a client-side web application that combines military-grade encryption (AES) with image steganography to hide files inside standard images. Unlike simple LSB tools, StegnaVault Pro uses a custom parity-based encoding algorithm spread across pixel blocks, ensuring data integrity and minimal visual distortion.

The core module that encrypts files and embeds them into a "carrier" image.

• Full Privacy: Encrypts filenames, file types, and sizes. Even if the steganography is detected, the metadata remains hidden.
• Capacity Calculation: Automatically calculates max file size based on image resolution.

Retrieves hidden data from stego-images.

• Integrity Check: Uses a hidden "Verifier Token" to instantly reject incorrect passwords without generating corrupted files.
• Auto-Restoration: Restores the original filename and file type automatically upon successful decryption.

A diagnostic tool to analyze images.

• Header Detection: Scans for the proprietary <ICRYPT> signature.
• Privacy Safe: Confirms the presence of hidden data without revealing what it is (since headers are now encrypted).

Increases the storage capacity of small images using specific algorithms.

• Nearest Neighbor: Upscales images without blurring, preserving sharp edges ideal for pixel manipulation.
• Scale: Supports up to 32x upscaling for massive storage potential.

A graphical representation of the hidden data structure.

• Shows the memory distribution (Header, Encrypted Payload, Free Space).

A forensic tool to compare Original vs. Stego images.

• Slider View: Interactive swipe to see visual differences.
• Difference Map: Subtracts pixel values to highlight modified bits in red.

Instead of the standard Least Significant Bit (LSB) method which can be fragile, StegnaVault Pro uses a custom Parity Encoding Scheme distributed over 3-pixel blocks.

1. The Grid: The image is treated as a linear array of pixels.
2. The Block: We group every 3 pixels together.
   • 3 Pixels = 9 Color Channels (R, G, B x 3).
3. The Payload: Each block stores 1 Byte (8 bits) of data + 1 Parity Bit.
4. Encoding Logic:
   • The algorithm reads the bit (0 or 1).
   • It adjusts the channel value to be Even (for 0) or Odd (for 1).
   • Example: If we need to store a 1 (Odd) and the Red channel is 200 (Even), it changes to 201.
   • This creates a minimal change (+/- 1 value) invisible to the human eye.

Capacity Formula:

$$\text{Capacity (Bytes)} \approx \frac{\text{Width} \times \text{Height}}{3}$$

StegnaVault Pro employs a "Wrap-then-Encrypt" strategy using CryptoJS (AES).

Before encryption, the file is wrapped in a JSON structure:

{
  "verifier": "ICRYPT_OK",
  "meta": {
    "n": "secret_plans.pdf",
    "t": "application/pdf",
    "s": 10240
  },
  "data": "base64_encoded_string..."
}

The object above is stringified and AES-encrypted. It is then sandwiched between magic signatures: <ICRYPT> + [AES ENCRYPTED BLOB] + </ICRYPT>

When decrypting, the app first looks for the verifier key: "ICRYPT_OK".

• If Pass is Correct: The token is found, and the file is extracted.
• If Pass is Wrong: The decryption produces garbage, the token is missing, and the app throws an "Integrity Check Failed" error.

• Core: HTML5, JavaScript (ES6+).
• UI Framework: Tailwind CSS (via CDN).
• Cryptography: crypto-js (AES implementation).
• Icons: Lucide Icons.
• Font: JetBrains Mono (Google Fonts).

1. Image Formats:
   • Always save/share the output as PNG.
   • Never convert the output to JPG/JPEG. JPEG compression destroys the specific odd/even pixel values, corrupting the data.
2. Maximizing Capacity:
   • If your image is too small for your file, use the Resizer tab.
   • Select "Nearest Neighbor" for the cleanest upscale.
   • A 1920x1080 image can hold approx 690 KB.
   • Upscaling by 2x quadruples the capacity.
3. Password Safety:
   • Because the filename and type are inside the encrypted blob, if you lose the password, you lose the file type information too. You won't know if the hidden file was a PDF or an Image.

The following features are planned for future iterations of StegnaVault:

1. Incorporating JPEG Files: Developing DCT (Discrete Cosine Transform) modification algorithms to allow data hiding that survives JPEG compression.
2. Audio Steganography: Extending the parity encoding logic to WAV audio samples or MP3 frames to hide data in sound files.
3. Video Steganography: Hiding data across frames in video files, utilizing the vast storage capacity of video containers.

StegnaVault Pro is a single-file application (stegnaVault_pro.html).

1. Download the .html file.
2. Open it in any modern web browser (Chrome, Firefox, Edge, Safari).
3. No server or internet connection is required (it runs entirely offline).

version Details.md

This tool is for educational and privacy-protection purposes. Users are responsible for complying with local laws regarding encryption and data hiding.