ISpectrogramViewer

Spectrogram viewer canvas controller and inspector.

Extends

• IDataViewer.NavigableViewer

Properties

Property	Type	Inherited from
getTimeBounds?	() => TimeBounds	NavigableViewer.getTimeBounds

Methods

canvasToTimeFrequency()

canvasToTimeFrequency(x: number, y: number): object;

Converts canvas pixel coordinates to time (seconds) and frequency (Hz).

Parameters

Parameter	Type
x	number
y	number

Returns

object

frequency

frequency: number;

time

time: number;

Overrides

NavigableViewer.canvasToTimeFrequency

---

clearCache()

clearCache(): void;

Clears cached STFT tiles from memory.

Returns

void

---

destroy()

destroy(): void;

Disposes the renderer, WebGL resources, and event listeners.

Returns

void

Overrides

IDataViewer.destroy

---

getCacheStats()

getCacheStats(): CacheStats;

Returns current STFT tile cache statistics.

Returns

CacheStats

---

getCanvas()

getCanvas(): HTMLCanvasElement;

Returns the bound HTML canvas element.

Returns

HTMLCanvasElement

Overrides

NavigableViewer.getCanvas

---

getConfig()

getConfig(): ResolvedSpectrogramConfig;

Returns the resolved spectrogram configuration options.

Returns

ResolvedSpectrogramConfig

Overrides

NavigableViewer.getConfig

---

getFrequencyBounds()

getFrequencyBounds(): object;

Returns the full available frequency bounds in Hz.

Returns

object

maxFrequency

maxFrequency: number;

minFrequency

minFrequency: number;

Overrides

NavigableViewer.getFrequencyBounds

---

getFrequencyScale()

getFrequencyScale(): FrequencyScale;

Returns the active frequency scale (linear, log, or mel).

Returns

FrequencyScale

---

getNyquist()

getNyquist(): number;

Returns the Nyquist frequency in Hz.

Returns

number

---

getRendererKind()

getRendererKind(): "webgl2" | "canvas2d";

Returns the active rendering engine (webgl2 or canvas2d).

Returns

"webgl2" | "canvas2d"

---

getScope()?

optional getScope(): object;

Returns

object

getDuration()

getDuration(): number;

Returns

number

getSampleRate()?

optional getSampleRate(): number | undefined;

Returns

number | undefined

Inherited from

NavigableViewer.getScope

---

getSource()

getSource(): AudioSource;

Returns the active audio source.

Returns

AudioSource

---

getStatus()

getStatus(): SpectrogramStatus;

Returns the current render status.

Returns

SpectrogramStatus

---

getTileStates()

getTileStates(): TileStateInfo[];

Returns status information for all computation tiles.

Returns

TileStateInfo[]

---

getViewport()

getViewport(): ViewportConfig;

Returns the visible time and frequency viewport.

Returns

ViewportConfig

Overrides

NavigableViewer.getViewport

---

getViewportController()

getViewportController(): IViewportController;

Returns the bound viewport controller.

Returns

IViewportController

---

on()

on<Name>(name: Name, handler: (event: SpectrogramEvents[Name]) => void): () => void;

Subscribes to spectrogram events.

Type Parameters

Type Parameter
Name extends keyof SpectrogramEvents

Parameters

Parameter	Type
name	Name
handler	(event: SpectrogramEvents[Name]) => void

Returns

() => void

---

queryCanvasPoint()

queryCanvasPoint(input: object): Promise<SpectrumPoint>;

Queries the spectral intensity value at canvas pixel coordinates.

Parameters

Parameter	Type	Description
input	{ channel?: number; mode?: ValueMode; x: number; y: number; }	Canvas X and Y in pixels, optional channel, and value mode.
input.channel?	number	-
input.mode?	ValueMode	-
input.x	number	-
input.y	number	-

Returns

Promise<SpectrumPoint>

---

queryFrame()

queryFrame(input: object): Promise<SpectrumSlice>;

Queries spectral magnitudes for a specific STFT frame index.

Parameters

Parameter	Type	Description
input	{ channel?: number; frameIndex: number; mode?: ValueMode; }	Frame index, optional channel, and value mode.
input.channel?	number	-
input.frameIndex	number	-
input.mode?	ValueMode	-

Returns

Promise<SpectrumSlice>

---

queryPoint()

queryPoint(input: object): Promise<SpectrumPoint>;

Queries the spectral intensity value at a specific time and frequency.

Parameters

Parameter	Type	Description
input	{ channel?: number; frequency: number; mode?: ValueMode; time: number; }	Time in seconds, frequency in Hz, optional channel, and value mode.
input.channel?	number	-
input.frequency	number	-
input.mode?	ValueMode	-
input.time	number	-

Returns

Promise<SpectrumPoint>

---

querySpectrum()

querySpectrum(input: object): Promise<SpectrumSlice>;

Queries spectral magnitudes across all frequency bins at a specific timestamp.

Parameters

Parameter	Type	Description
input	{ channel?: number; mode?: ValueMode; time: number; }	Target time in seconds, optional channel, and value mode.
input.channel?	number	-
input.mode?	ValueMode	-
input.time	number	-

Returns

Promise<SpectrumSlice>

---

render()

render(): Promise<void>;

Renders the current spectrogram viewport asynchronously.

Returns

Promise<void>

---

requestRender()

requestRender(): void;

Schedules a render on the next animation frame.

Returns

void

Overrides

NavigableViewer.requestRender

---

setConfig()

setConfig(input: Partial<SpectrogramOptions>): void;

Alias for updateConfig.

Parameters

Parameter	Type
input	Partial<SpectrogramOptions>

Returns

void

---

setSource()

setSource(source: AudioSource): void;

Updates the audio source and invalidates the tile cache.

Parameters

Parameter	Type
source	AudioSource

Returns

void

Overrides

IDataViewer.setSource

---

setViewport()

setViewport(viewport: Partial<ViewportConfig>): void;

Parameters

Parameter	Type
viewport	Partial<ViewportConfig>

Returns

void

Inherited from

NavigableViewer.setViewport

---

timeFrequencyToCanvas()

timeFrequencyToCanvas(time: number, frequency: number): object;

Converts time (seconds) and frequency (Hz) to canvas pixel coordinates.

Parameters

Parameter	Type
time	number
frequency	number

Returns

object

x

x: number;

y

y: number;

Overrides

NavigableViewer.timeFrequencyToCanvas

---

updateConfig()

updateConfig(input: Partial<SpectrogramOptions>): void;

Updates configuration options and triggers a re-render.

Parameters

Parameter	Type
input	Partial<SpectrogramOptions>

Returns

void