g722-spandsp

Node-API bindings for SpanDSP G.722 (encode/decode).
Minimal, fast, production-friendly. Works with ESM and CommonJS.

⚠️ This package links dynamically against system libspandsp (LGPL-2.1).
Your app remains MIT/closed as long as you dynamically link and ship the LGPL notice.

Install

macOS (Apple Silicon / Intel)

brew install spandsp pkg-config
npm i g722-spandsp
# or from source in this repo:
npm install
npm run build

Debian/Ubuntu

sudo apt-get update
sudo apt-get install -y build-essential python3 pkg-config libspandsp-dev
npm i g722-spandsp

Windows is not supported.

Usage

ESM

import { G722Encoder, G722Decoder } from 'g722-spandsp';

// 20 ms of 1 kHz @ 16 kHz PCM16LE
const sr = 16000, ms = 20, n = sr*ms/1000;
const pcm = Buffer.alloc(n*2);
let ph=0, w=2*Math.PI*1000/sr;
for (let i=0;i<n;i++){ pcm.writeInt16LE(Math.round(Math.sin(ph)*12000), i*2); ph+=w; }

const enc = new G722Encoder();
const g = enc.encode(pcm);      // ~160 bytes (64 kbps)

const dec = new G722Decoder();
const back = dec.decode(g);     // ~320 samples PCM16

CommonJS

const { G722Encoder, G722Decoder } = require('g722-spandsp');

API

• new G722Encoder()
  • encode(pcm16le: Buffer|Uint8Array): Buffer — encodes to G.722 octet-aligned (64 kbps).
  • reset(): void
• new G722Decoder()
  • decode(g722: Buffer|Uint8Array): Buffer — decodes to PCM16LE @ 16 kHz.
  • reset(): void

Notes

• G.722 audio sample rate is 16 kHz.
  RTP timestamps tick at 8 kHz (RFC quirk).
• The addon uses G722_PACKED (octet-aligned) payloads.

Build from source (in this repo)

npm install
npm run build
node test/test.js

License

• Code here: MIT (see LICENSE)
• Runtime dependency: SpanDSP (LGPL-2.1) — dynamically linked.