Aug 2026 – Sep 2026
Eye portrait line art
A photo of a pair of eyes turned into line art ready for laser engraving on silver
- AI
- AI image pipeline
- Duration
- 1 month
- Role
- Sole owner
Overview
A small Node.js tool that turns a photo of a person’s eyes into black-and-white line art with Gemini 3 Pro Image, then into a transparent PNG that an xTool F1 laser can engrave on silver. The hard part is keeping the likeness in pure black lines about 3 cm wide.
Tools
- Node.js
- Gemini
- sharp
- xTool F1
Likeness in pure lines
A laser engraver cannot reproduce halftones, so the photo has to become pure black lines on transparency, about 3 cm wide, while keeping the likeness: the eyelid opening, the corners, the crease and the asymmetry. General image models tend to idealise faces and add stray marks.
Seven prompts
A script sends the photo with a prompt file to Gemini 3 Pro Image and generates several variants in parallel. Seven prompt iterations moved from a grayscale photographic print to a copperplate, banknote-style etching, with strict rules: only brows and eyes, the exact eye opening and asymmetry, brows completed where the crop cuts them, pure black and white, and line spacing suited to a 3 cm engraving.
From image to laser file
With sharp, the output becomes a binary mask at threshold 140, so each pixel is either pure black or fully transparent. A cleanup script finds connected strokes, removes isolated marks in the central band around the nose, and writes a clean transparent PNG, a white-background PNG and a preview on silver. A cost file tracks API spend against a budget.
Result
Two rounds, in August and September 2026, took 24 API calls in total and stayed within budget.