wavefile

For browser environments (IE10+), you can include wavefile via a <script> tag using the file in the dist folder or via a CDN like jsDelivr or unpkg.

<!-- Using local dist file -->
<script src="wavefile.js"></script>
<script>
  var wav = new wavefile.WaveFile();
</script>

<!-- Using jsDelivr CDN -->
<script src="https://cdn.jsdelivr.net/npm/wavefile"></script>

<!-- Using unpkg CDN -->
<script src="https://unpkg.com/wavefile"></script>

You can import wavefile in Node.js using CommonJS or ESM syntax. The primary class for interacting with audio files is WaveFile.

// CommonJS option 1
const wavefile = require('wavefile');
let wav = new wavefile.WaveFile();

// CommonJS option 2
const WaveFile = require('wavefile').WaveFile;
let wav = new WaveFile();

// ESM option
import { WaveFile } from 'wavefile';
let wav = new WaveFile();

Install wavefile via npm for use in your projects:

npm install wavefile

To use wavefile as a global command line tool, install it with the -g flag:

npm install wavefile -g

This example demonstrates how to load a WAV file from a buffer, inspect its properties, and export the data as a Buffer or a DataURI.

const WaveFile = require('wavefile').WaveFile;

// Load a wav file buffer as a WaveFile object
let wav = new WaveFile(buffer);

// Check some of the file properties
console.log(wav.container);
console.log(wav.chunkSize);
console.log(wav.fmt.chunkId);

// Call toBuffer() to get the bytes of the file.
// You can write the output straight to disk:
let wavBuffer = wav.toBuffer();

// Call toDataURI() to get the file as a DataURI:
let wavDataURI = wav.toDataURI();

RIFF tags (like ICMT) can be managed using these methods:

• setTag(tag, value): Creates or overwrites a tag.
• getTag(tag): Returns the value of the tag if it exists.
• deleteTag(tag): Deletes the specified tag.

// Write the ICMT tag
wav.setTag("ICMT", "some comments");

// Get the tag
console.log(wav.getTag("ICMT"));

// Delete the tag
wav.deleteTag("ICMT");

You can manipulate metadata tags within the RIFF INFO chunk:

• setTag(tag, value): Writes or overwrites a tag.
• getTag(tag): Returns the value of a tag, or null if not found.
• deleteTag(tag): Removes a tag. Returns true if deleted.
• listTags(): Returns an object containing all tags in the file.

waveFile.setTag('artist', 'John Doe');
const artist = waveFile.getTag('artist');
const allTags = waveFile.listTags();

You can create a new WaveFile instance in two ways:

1. Empty instance: Creates a blank WaveFile object.
2. From a buffer: Creates a WaveFile object by parsing an existing .wav file buffer (Uint8Array). This will throw an error if the required RIFF, fmt , or data chunks are missing.

Note: When using WaveFile(wav), the input must be a Uint8Array.

// Create an empty WaveFile object
WaveFile();

// Create a WaveFile object with the contents of a wav file buffer
WaveFile(wav);

The WaveFile object can be exported into several formats for storage or web usage:

• Buffer: toBuffer() returns a Uint8Array representing the .wav file, suitable for writing directly to disk.
• Base64: toBase64() returns a .wav file encoded as a base64 string.
• DataURI: toDataURI() returns a .wav file as a DataURI, which can be used directly in browser src attributes (e.g., <audio>).

const buffer = waveFile.toBuffer();
const base64 = waveFile.toBase64();
const dataUri = waveFile.toDataURI();

You can populate a WaveFile instance by reading existing data using the following methods:

• fromBuffer(buffer): Read from a Buffer.
• fromBase64(base64): Read from a base64 encoded string.
• fromDataURI(dataURI): Read from a data URI.

const WaveFile = require('wavefile').WaveFile;
const wav = new WaveFile();

wav.fromBuffer(buffer);
wav.fromBase64(base64);
wav.fromDataURI(dataURI);

WaveFile supports cue points and regions (defined by a start and end position).

Creating a Cue Point: Use setCuePoint(pointData). The pointData object requires:

• position (number): Position in milliseconds.
• label (string, optional): A label for the point.
• end (number, optional): The end position in milliseconds (if provided, this creates a region).

Other Cue Point Operations:

• listCuePoints(): Returns an array of all cue point objects.
• updateLabel(pointIndex, label): Updates the label of a specific cue point (index starts at 1).
• deleteCuePoint(index): Removes a cue point by its 1-based index.

waveFile.setCuePoint({
  position: 500,
  label: 'intro',
  end: 1500
});

const points = waveFile.listCuePoints();
waveFile.updateLabel(1, 'new label');
waveFile.deleteCuePoint(1);

Use WaveFile.fromScratch() to build a new audio file by providing raw sample data and format specifications. This method resets any existing chunks.

Parameters:

• numChannels (number): Number of audio channels.
• sampleRate (number): Sample rate (e.g., 8000, 44100, 48000, 96000, 192000).
• bitDepth (string): Audio bit depth code. Valid values include '4', '8', '8a', '8m', '16', '24', '32', '32f', '64', or any integer string between '8' and '32' (e.g., '12').
• samples (Array|TypedArray): The raw audio samples.
• options (Object, optional): Use {'container': 'RIFX'} to force the container as RIFX.

WaveFile.fromScratch(numChannels, sampleRate, bitDepth, samples, options);