stringart

Work in progress.

This project generates string art versions of any image.

Feed it an image, and it will re-create it with a single string connected to nails.

Usage

Install maven >=3.6.2 and a java jdk >=11. Compile with:

$ mvn package

This generates a standalone command line application in cli/target/stringart.jar:

$ java -jar cli/target/stringart.jar --help
Usage:
    java -jar <jar_file> [flags] [options] <goal image>

Arguments:
   <goal image>          The goal image.

Flags:
   -help, -h             print help
   -quiet, -q            Quiet mode
   -disableEdgeWay       disables the rendering of the way the string goes around edges. Enables a 
                         ~4x faster rendering, but is less precise.

Options:
   -importanceImage, -i  An importance image, that ponderates the pixels of the goal image
   -output, -o           Output file for rendering the graphical result
   -diff, -d             Output file for a pixel to pixel difference between the rendering and the 
                         goal image
   -stringPath, -s       Output file for saving the string path

To run it on the sample files included in the project, use this command. It will run for 1 or 2 hours to generate the final result.

$ java -jar cli/target/stringart.jar \
	samples/einstein/goal_image.png \
	-i samples/einstein/importance_image.png

Related works

This project has had many inspiration sources:

The original idea came from Greek artist Petros Vrellis in 2016.

Vrellis idea was latter refined in 2018 by Michael Birsak et al. They proposed a "method for the automatic computation and digital fabrication of artistic string images" [1] (Matlab sources). When I began this project, I tried to implement an alternative implementation based on Genetic algorithms, but I ultimately failed and had to retreat to the amazing Birsak proposition.

[1] Michael Birsak et al. "String Art: Towards Computational Fabrication of String Images", Computer Graphics Forum (Proc. EUROGRAPHICS 2018), 37(2), April 2018.

Many other implentations are available on the internet:

• Knit, in C++, as part of a master thesis project;
• Strixel, in C++ with a GUI;
• Knitter, in Processing, by Christian Siegel;
• ThreadTone, in Python;
• Automate the art, also in Processing, is a project that appears on hackaday.io;
• A string art font by Erik Demaine;
• Mid-air Laser Image Display is a somehow similar project that appears on hackaday, but it relies on lasers instead of strings.

TODO list

• a GUI.
• CLI: show default values in the help.
• CLI: add a possibility to use a text string path file as a start point.
• CORE: before the upscaling step, run a genetic algo for avoiding local optimums. (see 1, 2)
• CORE: use GPUs if any.