Computational String Art

A Python-based algorithm capable of recreating an image using only straight lines, also known as string art.
This project was inspired by the mathematical concepts explained in this video:
https://youtu.be/WGccIFf6MF8

📌 Overview

Computational String Art simulates the physical process of creating string art by stretching threads between nails placed on a circular frame. The algorithm reconstructs a grayscale image by iteratively selecting the best possible straight lines that pass through the darkest regions of the image.

This project demonstrates the application of:

• Geometry
• Greedy optimization
• Image processing
• Computational graphics

It converts a photograph into a visually striking string-art-style reconstruction using only straight line segments.

Results

Lets take a quick peak how it will look after execution:

🎯 Target Audience

• Students interested in:
  • Algorithms
  • Image processing
  • Computational art
• General developers exploring:
  • Optimization techniques
  • Creative coding
  • Visual computing

🧠 How It Works (High-Level)

1. The input image is converted to grayscale and cropped into a perfect circle.
2. A fixed number of nails are placed uniformly along the circumference.
3. Starting from one nail, the algorithm:
   • Evaluates all valid connecting lines.
   • Chooses the line that passes through the darkest average region.
   • Draws that line.
   • Removes the used darkness from the reference image.
4. This process is repeated thousands of times, gradually reconstructing the image using only straight lines.

This method follows a greedy optimization strategy.

🛠 Installation & Setup

Requirements

pip install requirements.txt

▶ How to Run

This project is configured for manual parameter control.

-Open the Python file and edit:

path = r"YOUR_IMAGE_PATH"

BOARD_WIDTH = 80
PIXEL_WIDTH = 0.01
LINE_TRANSPARENCY = 0.3
NUM_NAILS = 300
MAX_ITERATIONS = 5000

Then run:

python main.py

⚙ Parameter Description

Parameter	Description
BOARD_WIDTH	Physical diameter of the circular board
PIXEL_WIDTH	Pixel resolution scaling factor
NUM_NAILS	Number of nails placed around the circle
MAX_ITERATIONS	Number of threads drawn
LINE_TRANSPARENCY	Transparency factor of thread overlay
path	Input image file path

Higher values of NUM_NAILS and MAX_ITERATIONS result in better quality but slower execution.

📂 Output Files

The program generates:

-output*.png → Final string art image -output_comparison.png → Side-by-side comparison (original vs generated) -results.txt → Sequence of nail connections

📊 Example Output

The comparison output shows: -Left → Original reference image -Right → Generated string art

This allows direct visual evaluation of reconstruction accuracy.

🧮 Mathematical Foundation

The algorithm is based on:

-Circular geometry -Parametric equations of a circle -Line integral minimization -Greedy optimization

At every step, the algorithm minimizes: Average Brightness Along Line

This ensures that each string contributes maximum structural detail to the final image.

🚀 Future Scope

Generating actual physical string art using the computed nail sequence. Exploring mechanical or CNC-assisted thread placement.

📜 License

This project is open-source and free for educational and personal use.

✍ Author

Arnab Datta

GitHub: https://github.com/Arnab500th