# ac3.js

> JavaScript AC-3 (ATSC A/52) decoder

Latest version **0.3.1** (published 2023-11-10) · MIT license · 0 weekly downloads

## Install

```sh
npm install ac3.js
pnpm add ac3.js
yarn add ac3.js
bun add ac3.js
```

## Health

**Score 30/100 (F)** — status: abandoned.

Positive: no vulnerabilities; high maintenance score.

Warnings: low downloads; no types; no esm support; pre 1.0.

Negative: abandoned.

## Facts

| | |
|---|---|
| Version | 0.3.1 |
| Published | 2023-11-10 |
| First published | 2018-09-28 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 3 |
| Unpacked size | 374.5 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 10 |
| Maintainers | daniellehuisman |
| Keywords | atsc, a52, ac3, ac-3, eac3, eac-3, audio, decoder, browser |

## Links

- npm: https://www.npmjs.com/package/ac3.js
- Repository: https://github.com/DanielleHuisman/ac3.js
- npm.io page: https://npm.io/package/ac3.js

## Dependencies (3)

- [av](https://npm.io/package/av.md) ^0.4.9
- [fft.js](https://npm.io/package/fft.js.md) ^4.0.3
- [@babel/runtime](https://npm.io/package/@babel/runtime.md) ^7.23.2

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## Recent versions

- 0.3.1 (latest) — 2023-11-10
- 0.3.0 — 2023-11-10
- 0.2.4 — 2019-09-07
- 0.2.3 — 2018-10-01
- 0.2.2 — 2018-09-30
- 0.2.1 — 2018-09-29
- 0.2.0 — 2018-09-29
- 0.1.0 — 2018-09-28

## README

# AC3.js

JavaScript AC-3 (ATSC A/52) decoder for the [Aurora.js](https://github.com/audiocogs/aurora.js) audio framework.

## Installation

```bash
yarn add ac3.js
```

## Usage

### Simple

```javascript
import {AC3SimpleDecoder} from 'ac3.js';
import fs from 'fs';

// This example loads an AC-3 audio file and writes the PCM data to file.
// The output file is in PCM signed 16-bit interleaved format.

// Initialize input and output stream
const inputStream = fs.createReadStream('example.ac3');
const outputStream = fs.createWriteStream('example.pcm');

// Initialize simple decoder
const simpleDecoder = new AC3SimpleDecoder(inputStream);

// Write PCM data to output stream (data is an Uint8Array)
simpleDecoder.on('data', (data) => {
    outputStream.write(data);
});
```

### Aurora.js

```javascript
import {AC3Decoder, AC3Demuxer} from 'ac3.js';
import AV from 'av';

// This example loads an AC-3 audio file and plays it.
// - In Node.js this should play the audio using the speaker module.
// - In the browser this should play the audio using the Web Audio API.

// Register demuxer and decoder
AV.Demuxer.register(AC3Demuxer);
AV.Decoder.register('ac3', AC3Decoder);

// Initialize player
const player = AV.Player.fromURL('https://example.org/example.ac3');

player.on('format', (format) => console.log('format', format));
player.on('duration', (duration) => console.log('duration', duration));
player.on('progress', (progress) => console.log('progress', progress));
player.on('ready', () => console.log('ready'));
player.on('end', () => console.log('end'));
player.on('error', (error) => console.error(error));

// Start the player
player.play();
```

For detailed information on how to use Aurora.js, check out the [documentation](https://github.com/audiocogs/aurora.js/wiki).

## Authors

-   [Danielle Huisman](https://github.com/DanielleHuisman)
-   [Karl Koscher](https://github.com/supersat)

## License

AC3.js is available under the terms of the MIT license.

## Progress

### Syntax implementation

-   [x] `syncframe`
    -   [x] `syncinfo`
    -   [x] `bsi`
    -   [x] `audblk`
    -   [x] `auxdata`
    -   [x] `errorcheck`

### Decoding implementation

-   [x] Input Bit Stream
-   [x] Synchronization
-   [ ] Error Detection
-   [x] Unpack BSI
-   [x] Unpack Side Information
-   [x] Decode Exponents
-   [x] Bit Allocation
-   [x] Process Mantissas
-   [x] Decoupling
-   [x] Rematrixing
-   [x] Inverse Transform
-   [x] Window, Overlap/Add
-   [x] Downmixing
-   [x] PCM Output Buffer
-   [x] Output PCM

### Roadmap

-   Support all downmixing modes
-   Support Enhanced AC-3 (E-AC-3)
-   Error detection
-   Unit tests

---
_Source: https://npm.io/package/ac3.js · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._