BufferInput

Server-side audio input provider that accepts pushed audio buffers.

Defined in: src/providers/input/BufferInput.ts:117

Server-side audio input provider that accepts pushed audio buffers.

Remarks

BufferInput allows server-side applications to feed audio data into the CompositeVoice pipeline without any browser dependencies. The application pushes raw audio via push(), and BufferInput wraps each buffer into an AudioChunk with a timestamp and sequence number before delivering it to the registered callback.

The audio format is declared up-front in the constructor via AudioMetadata, enabling the pipeline to auto-configure STT encoding/sample-rate settings without needing to sniff audio frames.

Data-flow diagram:

app.push(data) ──> BufferInput ──callback(chunk)──> InputQueue ──> STT
                       |
                 active=true?
                   yes: emit
                   no:  drop

Example

import { BufferInput } from 'composite-voice';
import { createReadStream } from 'node:fs';

const input = new BufferInput({
  sampleRate: 16000,
  encoding: 'linear16',
  channels: 1,
  bitDepth: 16,
});

await input.initialize();
input.onAudio((chunk) => {
  console.log(`Received ${chunk.data.byteLength} bytes, seq=${chunk.sequence}`);
});
input.start();

// Stream audio from a file
const stream = createReadStream('audio.raw', { highWaterMark: 4096 });
stream.on('data', (buf: Buffer) => input.push(buf.buffer));

See

AudioInputProvider for the interface contract
MicrophoneInput for the browser-side counterpart
NullOutput for the server-side output counterpart

Implements

AudioInputProvider

Constructors

Constructor

new BufferInput(metadata): BufferInput;

Defined in: src/providers/input/BufferInput.ts:176

Creates a new BufferInput instance.

Parameters

Parameter	Type	Description
`metadata`	`AudioMetadata`	Format description for the audio that will be pushed. Must include at least `sampleRate`, `encoding`, and `channels`.

Returns

BufferInput

Remarks

The metadata parameter declares the audio format that will be pushed via push(). This metadata is returned by getMetadata() and used by the pipeline to auto-configure the downstream STT provider.

Example

const input = new BufferInput({
  sampleRate: 16000,
  encoding: 'linear16',
  channels: 1,
  bitDepth: 16,
});

Properties

Property	Modifier	Type	Default value	Description	Defined in
`roles`	`readonly`	readonly `ProviderRole`[]	`undefined`	Pipeline roles covered by this provider. Remarks `BufferInput` is a single-role provider covering only the `'input'` slot. It requires a separate STT provider for the `'stt'` role.	src/providers/input/BufferInput.ts:134
`type`	`readonly`	`ProviderType`	`'rest'`	Communication type for this provider. Remarks `BufferInput` uses `'rest'` because it does not maintain a persistent connection — audio is pushed imperatively by the application.	src/providers/input/BufferInput.ts:125

Methods

dispose()

dispose(): Promise<void>;

Defined in: src/providers/input/BufferInput.ts:201

Dispose of the provider and release all resources.

Returns

Promise<void>

Remarks

Stops accepting audio, clears the callback reference, and resets the sequence counter. After disposal the instance should not be reused.

Implementation of

AudioInputProvider.dispose

getMetadata()

getMetadata(): AudioMetadata;

Defined in: src/providers/input/BufferInput.ts:306

Get the audio format metadata for the audio being pushed.

Returns

AudioMetadata

A copy of the AudioMetadata provided to the constructor.

Remarks

Returns the metadata provided at construction time. Used by the pipeline to auto-configure STT encoding, sample rate, and channel settings via configureSTTFromMetadata().

Implementation of

AudioInputProvider.getMetadata

initialize()

initialize(): Promise<void>;

Defined in: src/providers/input/BufferInput.ts:189

Initialize the provider, making it ready to accept audio.

Returns

Promise<void>

Remarks

A no-op beyond setting the initialized flag, since BufferInput has no external resources to acquire. If already initialized, this is a no-op.

Implementation of

AudioInputProvider.initialize

isActive()

isActive(): boolean;

Defined in: src/providers/input/BufferInput.ts:277

Check whether the provider is actively emitting audio.

Returns

boolean

true when started and not paused.

Implementation of

AudioInputProvider.isActive

isReady()

isReady(): boolean;

Defined in: src/providers/input/BufferInput.ts:216

Check whether the provider has been initialized.

Returns

boolean

true when initialize has completed and dispose has not yet been called.

Implementation of

AudioInputProvider.isReady

onAudio()

onAudio(callback): void;

Defined in: src/providers/input/BufferInput.ts:292

Parameters

Parameter	Type	Description
`callback`	(`chunk`) => `void`	Function invoked with each AudioChunk when audio is pushed and the provider is active.

Returns

void

Remarks

Only one callback can be registered at a time; subsequent calls replace the previous callback. Must be called before start().

Implementation of

AudioInputProvider.onAudio

pause()

pause(): void;

Defined in: src/providers/input/BufferInput.ts:255

Temporarily pause audio emission without stopping the provider.

Returns

void

Remarks

Audio pushed while paused is silently dropped. Resume with resume().

Implementation of

AudioInputProvider.pause

push()

push(data): void;

Defined in: src/providers/input/BufferInput.ts:334

Push raw audio data into the pipeline.

Parameters

Parameter	Type	Description
`data`	`ArrayBuffer`	Raw audio bytes matching the format declared in the constructor’s AudioMetadata.

Returns

void

Remarks

Wraps the raw ArrayBuffer into an AudioChunk with a timestamp and monotonically increasing sequence number, then delivers it to the registered callback. If the provider is not active (not started, stopped, or paused), the data is silently dropped.

Example

// Push PCM audio from a Node.js Buffer
const pcmBuffer = Buffer.alloc(3200); // 100ms of 16kHz 16-bit mono
input.push(pcmBuffer.buffer);

// Push from a WebSocket message
ws.on('message', (data: ArrayBuffer) => input.push(data));