woff2-encoder

A TypeScript library for handling WOFF2 encoding using WebAssembly.

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🚀 Getting Started

Prerequisites

• If using Node, >= 18.x

Installation

npm install woff2-encoder

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Notes

If you only need to decompress WOFF2 files, it's recommended that you import from woff2-encoder/decompress (see the Decompress only example below). This will net your end users a significant decrease in bundle size as it uses its own separate WASM file with a much smaller footprint.

📚 API Reference

compress

Compresses SFNT (TrueType/OpenType) font data to WOFF2 font data.

Returns: Promise<Uint8Array> A promise resolving to the WOFF2 font data.

Parameter	Type	Description
buffer	ArrayBuffer | Uint8Array	The SFNT font data.

decompress

Decompresses WOFF2 font data back to SFNT (TrueType/OpenType) font data.

Returns: Promise<Uint8Array> A promise resolving to the SFNT font data.

Parameter	Type	Description
buffer	ArrayBuffer | Uint8Array	The WOFF2 font data.

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💡 Examples

Compress a TTF font using Node.js

import fs from 'node:fs';
import { compress } from 'woff2-encoder';

async function example() {
  const fontFile = fs.readFileSync('./my-font.ttf');
  const output = await compress(fontFile);
}

Decompress a WOFF2 font from a URL

import { decompress } from 'woff2-encoder';

async function example() {
  const fontBuffer = await fetch('https://example.com/my-font.woff2').then(
    (res) => res.arrayBuffer()
  );

  const output = await decompress(fontBuffer);
}

Parse a WOFF2 font with opentype.js

import fs from 'node:fs';
import opentype from 'opentype.js';
import { decompress } from 'woff2-encoder';

async function example() {
  const fontFile = fs.readFileSync('./my-font.woff2');
  const output = await decompress(fontFile);

  // Since opentype.js requires a buffer, we pass
  // in the buffer and not the byte array itself
  const fontData = opentype.parse(output.buffer);
}

Decompress only

import fs from 'node:fs';
import opentype from 'opentype.js';
import decompress from 'woff2-encoder/decompress';

async function example() {
  const fontBuffer = await fetch('https://example.com/my-font.woff2').then(
    (res) => res.arrayBuffer()
  );

  const output = await decompress(fontBuffer);
}

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⭐ Acknowledgements

• google/woff2 - For the C++ implemention for encoding WOFF2 files.
• fontello/wawoff2 - For the initial WebAssembly port of Google's WOFF2 encoder.

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📃 License

MIT License. See LICENSE for details.