Byte-stable
Repeated runs are byte-identical when the input bytes, options, Kurviq version, and platform are unchanged. Cache and review generated assets with confidence.
Raster → SVG for Node.js
Deterministic vector tracing, without the toolchain.
Kurviq turns PNGs and JPEGs into SVG using a fast WebAssembly engine. It has zero runtime dependencies and produces byte-identical output for the same input, options, version, and platform.
One command
npx kurviq --input in.png --output out.svg- Runtime deps
- 0
- Engine
- Wasm
- Node.js
- 18+
Why Kurviq
A predictable part of your build.
The tracer is designed for repeatable pipelines, not a manual export dialog.
Self-contained Wasm
The vector engine ships with the package. There is no separate native executable to install and no runtime dependency tree to pull into production.
CLI and Node API
Use the command line in asset scripts, or call the synchronous CommonJS API with a Buffer or Uint8Array. The same options apply in both surfaces.
Capabilities
Recipes for the pixels that usually break tracing.
Start with defaults, then add one deliberate correction for the source you actually have.
--upscale 2 Upscale before tracing
Use --upscale 2 for small labels and fine edges. Kurviq expands the working pixels while preserving the original SVG display size.
--remove-background auto Remove real backgrounds
Border-connected removal handles uniform cells and attached neutral shadows, with channel protection for narrow gaps and near-white artwork.
--alpha-mode auto Handle soft alpha
Auto mode detects meaningful partial transparency, resizes alpha-aware, and thresholds the result without letting hidden RGB bleed into the trace.
--sharpen Sharpen flat artwork
Recover a compact palette from blurry icons before vectorization. The bare flag uses at most 12 colors and stays deterministic.
--mode spline Fit smooth splines
A tested spline recipe keeps rounded icon contours smooth without over-segmenting every anti-aliased edge.
--gradient_step 8 Preserve gradients
Smaller gradient steps and full color precision retain soft shading when visual fidelity matters more than the smallest possible SVG.
Real outputs
Drag across raster and SVG.
These are real Kurviq traces, including small icons and a full infographic. File sizes are the source files shown.
Illustrations traced by Kurviq itself.
See all seven examples →
SVG Raster Doctor — soft-shaded 3D icon
Fine facial details, soft shadows, and rounded color transitions.
SVG Raster Barcode — small outline icon
Narrow bars and soft-alpha edges on a compact source.
SVG Raster Choice path — full illustration
A 1,448 × 1,086 illustration with small labels and broad flat regions.
The traced SVG is 131 KB at DSSIM 0.003 (lower is closer).
Install and run
One package. Two entry points.
Install from npm, run the CLI immediately, or convert bytes and files from CommonJS.
CLI
Terminal
npm i kurviq
npx kurviq --input in.png --output out.svgNode API
JavaScript
const fs = require('node:fs');
const { convert, convertFile } = require('kurviq');
const svg = convert(fs.readFileSync('in.png'), {
mode: 'spline',
upscale: 2,
alphaMode: 'auto',
});
convertFile('in.png', 'out.svg', { preset: 'poster' }); Know the limits: conversion is synchronous, single-threaded, and CPU-bound. Kurviq traces pixels; it does not perform OCR or preserve selectable text. The current package targets Node.js and does not include a browser build.