Hashvis 
A Rust application for deterministic generation of images.
Hashvis is a small Rust application and library for generating very psychedelic images from an input string. The images are generated in a deterministic manner such that the same input string should always result in the same image being generated.
Hashvis is inspired by OpenSSH's VisualHostKey where the OpenSSH client will
display a deterministic piece of ASCII art generated from the host keys when
you are trying to authenticate with a remote server. The idea behind this
feature is that humans have an easier way to remember visual impressions than
long, hex-encoded, fingerprints.
Example usage could be:
- OpenSSH host keys (like with
VisualHostKeydescribed above). - OpenPGP public key fingerprints.
- Tor onion and next-generation onion public keys.
Currently Hashvis takes the user input string and passes it to the SHA3-256 hash function and uses this hash value to seed the ChaCha random number generator. The random number generator is then used to generate a lot of 64-bit floating-point values that are used to generate the expressions that is finally used to plot the RGB image.
Building Hashvis
To download and build Hashvis:
$ git clone https://github.com/ahf/hashvis.git
$ cd hashvis
$ cargo build
You can try running the application using:
$ cargo run --bin hashvis misc/examples/yourusername.png yourusername 256
Finished dev [unoptimized + debuginfo] target(s) in 0.0 secs
Running `target/debug/hashvis misc/examples/yourusername.png yourusername`
Generating image with SHA3("yourusername") in misc/examples/yourusername.png ...
R: f(x, y) = cos(pi * sin(pi * cos(pi * tan(pi * sin(pi * sin(pi * y) * y)) * y)))
G: f(x, y) = tan(pi * tan(pi * cos(pi * x * tan(pi * y) * x * x)) * tan(pi * sin(pi * sin(pi * x) * sin(pi * y))))
B: f(x, y) = tan(pi * x)
Feel free to submit a pull request if you think your generated image looks spectacular.
Testing Hashvis
To run the minimal test suite:
$ cargo test
Zooming In and Out
The factor argument that the Hashvis binary takes as an input allows you to
zoom in and out. A value smaller than 1.0 will zoom in, and anything larger
than 1.0 will zoom out of the normal view port. The default value is 1.0.
Authors
- Alexander Færøy ([email protected]).
Interactive Twitter Bot
Matthew Garrett (@mjg59) wrote a very cool interactive Twitter bot which fetches your Github SSH Public Key and executes Hashvis on the first key and tweets out the generated picture.
You can write your Github username to the bot and it will tweet out your, hopefully very unique, picture.
Check out the bot at https://twitter.com/github_idbot
Gallery
