Brainfreeze

A program to hide Brainf*ck programs inside images

This photo has the program that prints out "zetsuboii" hidden inside

Installation

1. Clone the repo and navigate inside
2. Run cargo build --release to build the project
3. Run target/release/brainfreeze help to see available commands

Usage

# Store a Brainf*ck program inside a PNG
# For now, only PNG format is supported
$ brainfreeze inject original.png hello.bfk -o hidden.png

# Run the program inside the PNG
$ brainfreeze run hidden.png

Wait, how does it even work?

Glad you asked.

Brainf*ck is a dead simple language that only has 9 tokens, including EOF. This makes hiding it quite simple.

In order to encode a brainf*ck token to image, I used differences of RGBA values between each pixel. It's uncommon to have the same difference between two pixels, and inside brainfreeze a token is represented by a constant color change.

As an optimization, tokens that can stack (>, <, + and -) are represented by a single token followed by empty pixels accounting for the stack amount.