svg2png-wasm

Demo site

SVG to PNG converter JS library made with WASM + resvg.

See resvg for SVG support status.

💻 Usage

Installation

Node.js / Browser

npm install svg2png-wasm
# yarn add svg2png-wasm
# pnpm add svg2png-wasm

Or, using a script tag in the browser and load from unpkg.

<script src="https://unpkg.com/[email protected]"></script>

<!-- Or, latest -->
<script src="https://unpkg.com/svg2png-wasm"></script>

Deno

// from esm.sh
export * from 'https://esm.sh/[email protected]';
// from skypack.dev
export * from 'https://cdn.skypack.dev/[email protected]?dts';

Examples

• Use in Web Worker Demo site (source)
• Use with Cloudflare Workers ssssota/svg2png-worker
• Use with Deno Deploy ssssota/svg2png-deno-deploy
• Or test directory

Node.js

import { svg2png, initialize } from 'svg2png-wasm';
// const { svg2png, initialize } = require('svg2png-wasm');
import { readFileSync, writeFileSync } from 'fs';

await initialize(
  readFileSync('./node_modules/svg2png-wasm/svg2png_wasm_bg.wasm'),
);

/** @type {Uint8Array} */
const png = await svg2png(
  '<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"> ... </svg>',
  {
    scale: 2, // optional
    width: 400, // optional
    height: 400, // optional
    backgroundColor: 'white', // optional
    fonts: [
      // optional
      readFileSync('./Roboto.ttf'), // require, If you use text in svg
    ],
    defaultFontFamily: {
      // optional
      sansSerif: 'Roboto',
    },
  },
);
writeFileSync('./output.png', png);

Browser

import { createSvg2png, initialize } from 'svg2png-wasm';

// put wasm to your assets directory
await initialize(fetch('/assets/svg2png_wasm_bg.wasm'));
const svgs = [
  '<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"> ... </svg>',
  '<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"> ... </svg>',
  '<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"> ... </svg>',
  // and more ...
];
const font = await fetch('./Roboto.ttf').then((res) => res.arrayBuffer());
const svg2png = createSvg2png({
  fonts: [new Uint8Array(font)], // require, If you use text in svg
});
/** @type {Uint8Array[]} */
const pngs = await Promise.all(svgs.map((svg) => svg2png(svg, { scale: 2 })));
svg2png.dispose(); // You should dispose svg2png, if you will not use it in the future

Or, using a script tag in the browser and load from esm.sh.

<img id="output" />
<script type="module">
  import * as svg2pngWasm from 'https://esm.sh/[email protected]';

  await svg2pngWasm.initialize(
    fetch('https://esm.sh/[email protected]/svg2png_wasm_bg.wasm'),
  );

  /** @type {Uint8Array} */
  const png = await svg2pngWasm.svg2png(
    '<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg"> ... </svg>',
  );
  document.getElementById('output').src = URL.createObjectURL(
    new Blob([png], { type: 'image/png' }),
  );
</script>

API

The library has two main APIs (svg2png and createSvg2png).

Basically, you can use svg2png, but if you want to process a lot of data continuously, consider using createSvg2png. It can reduce the overhead of font loading. Converters generated by createSvg2png should be disposed of after use by calling the dispose method.

export type InitInput =
  | RequestInfo
  | URL
  | Response
  | BufferSource
  | WebAssembly.Module;
export type DefaultFontFamily = {
  serifFamily?: string;
  sansSerifFamily?: string;
  cursiveFamily?: string;
  fantasyFamily?: string;
  monospaceFamily?: string;
};
export type ConverterOptions = {
  fonts?: Uint8Array[];
  defaultFontFamily?: DefaultFontFamily;
};
export type ConvertOptions = {
  scale?: number;
  width?: number;
  height?: number;
  backgroundColor?: string;
};
export type Svg2png = ((
  svg: string,
  options?: ConvertOptions,
) => Promise<Uint8Array>) & {
  dispose: () => void;
};
/**
 * Initialize WASM module
 * @param mod WebAssembly Module or WASM url
 */
export const initialize: (mod: Promise<InitInput> | InitInput) => Promise<void>;
/**
 * @param opts Converter options (e.g. font settings)
 * @returns svg2png converter
 */
export const createSvg2png: (opts?: ConverterOptions | undefined) => Svg2png;
export const svg2png: (
  svg: string,
  opts?: (ConverterOptions & ConvertOptions) | undefined,
) => Promise<Uint8Array>;

📄 LICENSE

MIT

This library uses resvg, which is licensed unser MPL-2.0. The source code for resvg can be found here.

🙋‍♂️ Contributing

WELCOME!