Kecleon

A simple web app that allows you to hide and reveal messages inside images using LSB steganography.

Supports optional password-based encryption for added security.

Features

• Hide messages inside images (LSB technique)
• Reveal hidden messages from images
• Optional password-based encryption
• Image capacity validation
• Safe PNG export to avoid data corruption
• Simple UI built with Streamlit

Installation

Installation using UV (recommended)

git clone <repo-url>
cd <repo>
uv sync

To run the app:

uv run streamlit run app.py

Installation using pip

git clone <repo-url>
cd <repo>
python -m venv .venv

Activate the environment:

Linux / macOS

source .venv/bin/activate

Windows

.venv\Scripts\activate

Install dependencies:

pip install -r requirements.txt

To run the app:

streamlit run app.py

Important notes

• Use PNG images to avoid data loss
• Do not use "Save as" from the browser — use the download button
• JPEG compression will destroy hidden data

How it works

This project uses Least Significant Bit (LSB) steganography:

• Each pixel stores 1 bit of the hidden message
• The message is optionally encrypted before embedding
• A header is added to detect valid hidden data
• The message is reconstructed during decoding until a null byte is found

Running tests

With uv

uv run pytest

With pip

pip install pytest
pytest

Future improvements

• Support for file embedding (not just text)
• Stronger encryption options
• Randomized pixel selection for better security
• Multi-channel encoding