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Class: AudioAnalyzer

Defined in: src/audio/AudioAnalyzer.ts:126

Reads a live frequency spectrum and feeds it into manim-web animations.

Constructors​

Constructor​

new AudioAnalyzer(options): AudioAnalyzer

Defined in: src/audio/AudioAnalyzer.ts:135

Parameters​

options​

AudioAnalyzerOptions = {}

Returns​

AudioAnalyzer

Accessors​

analyser​

Get Signature​

get analyser(): SpectrumAnalyser

Defined in: src/audio/AudioAnalyzer.ts:346

The connected analyser, or null when unavailable.

Returns​

SpectrumAnalyser

connected​

Get Signature​

get connected(): boolean

Defined in: src/audio/AudioAnalyzer.ts:336

Whether an analyser is connected (reads return live data).

Returns​

boolean

frequencyBinCount​

Get Signature​

get frequencyBinCount(): number

Defined in: src/audio/AudioAnalyzer.ts:341

The number of frequency bins the spectrum reads produce.

Returns​

number

Methods​

bindToTracker()​

bindToTracker(tracker, read, options): UpdaterFunction

Defined in: src/audio/AudioAnalyzer.ts:304

Drive a ValueTracker from an audio read each frame.

Adds an updater to the tracker that sets its value to offset + read() * scale on every update(dt). Other mobjects follow the tracker through their own updaters.

Parameters​

tracker​

ValueTracker

The tracker to drive

read​

() => number

Audio read to sample (defaults to getLevel)

options​

AudioReactiveBindOptions = {}

Scale and offset applied to the read

Returns​

UpdaterFunction

The updater, so it can be removed with tracker.removeUpdater

connectMediaElement()​

connectMediaElement(element): this

Defined in: src/audio/AudioAnalyzer.ts:183

Tap an <audio> / <video> element. Creates an owned AudioContext.

Parameters​

element​

HTMLMediaElement

Returns​

this

this for chaining

connectSource()​

connectSource(node): this

Defined in: src/audio/AudioAnalyzer.ts:204

Tap an existing AudioNode (for example a BufferSource or GainNode). The node's own AudioContext is used; no new context is created.

Parameters​

node​

AudioNode

Returns​

this

this for chaining

createUpdater()​

createUpdater<M>(apply): UpdaterFunction

Defined in: src/audio/AudioAnalyzer.ts:325

Build an updater that maps the spectrum onto any mobject property.

The returned updater passes the mobject, this analyzer, and dt to apply, so apply can read bands and set any property. Add it with mobject.addUpdater(analyzer.createUpdater(...)).

Type Parameters​

M​

M extends Mobject

Parameters​

apply​

(mobject, analyzer, dt) => void

Returns​

UpdaterFunction

dispose()​

dispose(): void

Defined in: src/audio/AudioAnalyzer.ts:351

Release the owned AudioContext, if this analyzer created one.

Returns​

void

getBand()​

getBand(lowHz, highHz): number

Defined in: src/audio/AudioAnalyzer.ts:242

Average the normalized energy [0, 1] across the band [lowHz, highHz]. Returns 0 when no analyser is connected or the band is empty.

Parameters​

lowHz​

number

highHz​

number

Returns​

number

getBass()​

getBass(): number

Defined in: src/audio/AudioAnalyzer.ts:257

Normalized bass energy [0, 1] (20-250 Hz).

Returns​

number

getByteFrequencyData()​

getByteFrequencyData(target?): Uint8Array

Defined in: src/audio/AudioAnalyzer.ts:220

Fill target (or an internal buffer) with the byte frequency spectrum. Returns a zero-filled buffer when no analyser is connected.

Parameters​

target?​

Uint8Array

Returns​

Uint8Array

The buffer that was written

getFrequencyData()​

getFrequencyData(): Uint8Array

Defined in: src/audio/AudioAnalyzer.ts:234

Alias of getByteFrequencyData that returns the internal buffer.

Returns​

Uint8Array

getLevel()​

getLevel(): number

Defined in: src/audio/AudioAnalyzer.ts:275

Overall loudness as the RMS [0, 1] of the time-domain waveform. Returns 0 when no analyser is connected.

Returns​

number

getMid()​

getMid(): number

Defined in: src/audio/AudioAnalyzer.ts:262

Normalized mid energy [0, 1] (250-4000 Hz).

Returns​

number

getTreble()​

getTreble(): number

Defined in: src/audio/AudioAnalyzer.ts:267

Normalized treble energy [0, 1] (4000-20000 Hz).

Returns​

number

fromAudioManager()​

static fromAudioManager(manager, options?): AudioAnalyzer

Defined in: src/audio/AudioAnalyzer.ts:163

Create an analyzer tapping the master output of an AudioManager. No-op (silent, returns zeros) when Web Audio is unavailable.

Parameters​

manager​

AudioManager

options?​

AudioAnalyzerOptions

Returns​

AudioAnalyzer

fromMediaElement()​

static fromMediaElement(element, options?): AudioAnalyzer

Defined in: src/audio/AudioAnalyzer.ts:152

Create an analyzer tapping an <audio> / <video> element. The element stays audible (the analyser is wired to the destination). No-op (silent, returns zeros) when Web Audio is unavailable.

Parameters​

element​

HTMLMediaElement

options?​

AudioAnalyzerOptions

Returns​

AudioAnalyzer