Custom Web String Art Generator

I create and sell string-art pieces and need my own browser-based generator so I can stop relying on paid tools like Zeta. The goal is a straightforward web app that lets me upload an image (JPEG, PNG or SVG), converts it into a peg-board outline, and then produces a numbered nail-and-string path I can print or save.

Core features I must have:
• Pattern templates I can tweak for different board sizes
• A custom image upload that automatically detects contrast, simplifies colours and lets me adjust nail count and circle radius before generating the path
• Automatic material recommendations showing thread length, nail count and colour breakdown based on the chosen pattern

A clear, intuitive interface is important because I’ll be using it while I design in the studio on both desktop and tablet browsers. I don’t mind which modern framework or vanilla stack you favour as long as the final code is clean, documented and easy for me to host myself.

Deliverables
• Responsive web application (HTML, CSS, JS + any framework you choose)
• Source code and build instructions in a Git repo or ZIP
• Brief user guide covering image prep, parameter controls and exporting the final pattern (PDF/PNG)

Acceptance criteria
1. I can open the site locally, load an image, adjust nails and instantly preview the generated string path.
2. The export file prints at the exact scale chosen and lists total thread length, colour suggestions and nail positions.
3. All features work in the latest Chrome, Firefox and Safari without extra plugins.

If this sounds like something you can build, please outline your proposed tech stack, estimated timeline and any similar visual-generation projects you have delivered.