Spectrogram

data

The outer array contains time frames; each inner array contains frequency-bin intensities.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• SpectrogramInput

  Type definition

width

Chart width in pixels. If the container width changes, update width from a ResizeObserver.

height

Chart height in pixels. Allow space for axes, titles, and the legend.

brandLogo

The default is the Syidax symbol and wordmark. With the Pro chart.branding entitlement, set none to remove it or provide a PNG, JPEG, or WebP data URL to replace it.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

brandPosition

The corner where the logo is anchored. Community and Pro both support all four corners, using the same position on screen and in image exports.

sampleRate

The sampling rate in Hz: the frequency axis then spans 0 … sampleRate / 2 (unless freq-min / freq-max say otherwise).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

freqMin

The frequency axis ends in Hz (default 0 … sampleRate / 2, else 0 … bins as bin indexes).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

freqMax

Set as an HTML attribute or JavaScript property. type: number.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

hopSeconds

Seconds per frame (the hop).

timeOrigin

Seconds at the first frame of the data (the window's drops advance it).

valueScale

linear or db.

• SpectrogramValueScale

  Type definition

dbFloor

The dB a zero magnitude reads (the linear scale).

samples

Raw samples (a property; ignored while data is set): the FFT pipeline frames them into dB.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

fftSize

The FFT size, a power of two (default 1,024): bins = fft-size / 2 and each bin is sample-rate / fft-size wide.

fftHop

Samples between frame starts (default fft-size / 2).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

fftWindow

The analysis window: hann (default), hamming, blackman, rect.

• SpectrogramWindowKind

  Type definition

colors

The colour ramp over the dB domain (a scheme name, a colour list / comma list, or [t, colour] stops).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

valueMin

Domain ends in dB; an omitted end follows the data (the min never more than 80 dB under the max).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

valueMax

Set as an HTML attribute or JavaScript property. type: number.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

emptyColor

The colour of an empty cell — transparent by default.

lod

The plane's level of detail: auto (area-folded once a frame or bin is under a device px — the usual case), point, area, smooth.

• SpectrogramLodMode

  Type definition

areaReduce

how the area LOD folds sub-pixel bins / frames: max (default, peak-hold — a narrow line survives) or mean.

xAxis

Configure the horizontal axis type, categories, range, and formatting. For a category axis, match the categories order to the value array indices. Charts supporting multiple axes can accept an axis array.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• CartesianAxisInput

  Type definition

yAxis

Configure the vertical axis range, ticks, labels, and direction. Use consistent units for comparisons, and consider a zero baseline when comparing bar lengths.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• YAxisInput

  Type definition

gridLines

Grid lines default OFF (the plane tiles the plot).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• CartesianGridLinesInput

  Type definition

crosshair

Crosshair that follows the cursor across the plot.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• CartesianCrosshairInput

  Type definition

zoom

Zoom (2026-09-10) — the shared cartesian zoom on the time (s) / frequency (Hz) axes: a mode ('x' | 'y' | 'xy'), true, 'inside' or the object (drag rectangle, pan, wheel, pinch, keyboard, reset button). Off by default.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• CartesianZoomInput

  Type definition

chartTitle

The title inside the chart. Explain the data's unit and meaning alongside it.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

chartSubtitle

The subtitle inside the chart.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

enableMouseTracking

Set as an HTML attribute or JavaScript property. type: boolean.

tooltip

the cell tooltip (the shared cartesian tooltip input: show / trigger / format / html / connector / draggable …).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• CartesianTooltipInput

  Type definition

tooltipEnabled

Set as an HTML attribute or JavaScript property. type: boolean.

tooltipFormat

a plain-text formatter of the default tooltip (tooltip.format wins).

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• SpectrogramPointEventDetail

  Type definition

animated

Whether to animate initial display and data changes.

animationDuration

Animation duration in milliseconds.

animationEasing

Allowed values: linear, ease-out, ease-in, ease-in-out. Default: 'ease-out'.

• SpectrogramEasing

  Type definition

animationType

Allowed values: initial, update. Default: undefined.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• SpectrogramAnimationType

  Type definition

streamSource

A stream source for live data. Check the contract for the specific type.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• SpectrogramStreamSource

  Type definition

streamMax

The scrolling window: frames kept at most (default 4,096) — the oldest scroll out first and the time origin advances.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

streamWindow

The newest N streamed frames the chart renders (the whole buffer when unset); the frames before the window stay buffered, the time axis starts at the window.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

visualMap

A visual-map binding (a sy-visual-map snapshot + dimension); it overrides colors / value-min / value-max while bound.

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

• VisualMapBinding

  Type definition

engine

auto, standard and pro all run the one WebGPU renderer (a Pro-only type has no other); switching never tears it down.

• SpectrogramEngineMode

  Type definition

unavailable

fallback shows the on-chart notice when the renderer cannot run; error throws.

• SpectrogramUnavailableBehaviour

  Type definition

rendered

Every drawn frame; engine is the engine status (requested / effective / code / the governing license feature).

Event name: rendered. Names are case-sensitive. Read the payload from detail on CustomEvent<SpectrogramRenderResult & { tier: SpectrogramEngineTier; engine?: ChartEngineStatus }>.

chart.addEventListener('rendered', event => {
  console.log(event.detail); // SpectrogramRenderResult & { tier: SpectrogramEngineTier; engine?: ChartEngineStatus }
});

• SpectrogramRenderResult

  Type definition

• SpectrogramEngineTier

  Type definition

• ChartEngineStatus

  Type definition

pointClick

A point selection event. Read the selected data and index from CustomEvent.detail.

Event name: pointClick. Names are case-sensitive. Read the payload from detail on CustomEvent<SpectrogramPointEventDetail>.

chart.addEventListener('pointClick', event => {
  console.log(event.detail); // SpectrogramPointEventDetail
});

• SpectrogramPointEventDetail

  Type definition

pointHover

CustomEvent.detail type: SpectrogramPointEventDetail | null. Event names are case-sensitive.

Event name: pointHover. Names are case-sensitive. Read the payload from detail on CustomEvent<SpectrogramPointEventDetail | null>.

chart.addEventListener('pointHover', event => {
  console.log(event.detail); // SpectrogramPointEventDetail | null
});

• SpectrogramPointEventDetail

  Type definition

crosshairMove

CustomEvent.detail type: CartesianCrosshairEventDetail | null. Event names are case-sensitive.

Event name: crosshairMove. Names are case-sensitive. Read the payload from detail on CustomEvent<CartesianCrosshairEventDetail | null>.

chart.addEventListener('crosshairMove', event => {
  console.log(event.detail); // CartesianCrosshairEventDetail | null
});

• CartesianCrosshairEventDetail

  Type definition

pointContextMenu

CustomEvent.detail type: ChartPointContextMenuEventDetail<SpectrogramPointEventDetail>. Event names are case-sensitive.

Event name: pointContextMenu. Names are case-sensitive. Read the payload from detail on CustomEvent<ChartPointContextMenuEventDetail<SpectrogramPointEventDetail>>.

chart.addEventListener('pointContextMenu', event => {
  console.log(event.detail); // ChartPointContextMenuEventDetail<SpectrogramPointEventDetail>
});

• ChartPointContextMenuEventDetail

  Type definition

• SpectrogramPointEventDetail

  Type definition

appended

CustomEvent.detail type: { count: number }. Event names are case-sensitive.

Event name: appended. Names are case-sensitive. Read the payload from detail on CustomEvent<{ count: number }>.

chart.addEventListener('appended', event => {
  console.log(event.detail); // { count: number }
});

windowSlid

CustomEvent.detail type: { dropped: number }. Event names are case-sensitive.

Event name: windowSlid. Names are case-sensitive. Read the payload from detail on CustomEvent<{ dropped: number }>.

chart.addEventListener('windowSlid', event => {
  console.log(event.detail); // { dropped: number }
});

chartAnimationStart

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: chartAnimationStart. Names are case-sensitive. Read the payload from detail on CustomEvent<void>.

chart.addEventListener('chartAnimationStart', event => {
  console.log(event.detail); // void
});

chartAnimationEnd

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: chartAnimationEnd. Names are case-sensitive. Read the payload from detail on CustomEvent<void>.

chart.addEventListener('chartAnimationEnd', event => {
  console.log(event.detail); // void
});

chartAnimationInterrupted

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: chartAnimationInterrupted. Names are case-sensitive. Read the payload from detail on CustomEvent<void>.

chart.addEventListener('chartAnimationInterrupted', event => {
  console.log(event.detail); // void
});

tooltipShow

Whether to display the built-in tooltip.

Event name: tooltipShow. Names are case-sensitive. Read the payload from detail on CustomEvent<CartesianTooltipEventDetail>.

chart.addEventListener('tooltipShow', event => {
  console.log(event.detail); // CartesianTooltipEventDetail
});

• CartesianTooltipEventDetail

  Type definition

tooltipHide

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: tooltipHide. Names are case-sensitive. Read the payload from detail on CustomEvent<void>.

chart.addEventListener('tooltipHide', event => {
  console.log(event.detail); // void
});

tooltipAction

CustomEvent.detail type: CartesianTooltipActionEventDetail. Event names are case-sensitive.

Event name: tooltipAction. Names are case-sensitive. Read the payload from detail on CustomEvent<CartesianTooltipActionEventDetail>.

chart.addEventListener('tooltipAction', event => {
  console.log(event.detail); // CartesianTooltipActionEventDetail
});

• CartesianTooltipActionEventDetail

  Type definition

zoomChange

Zoom — every zoom / pan change (drag, keyboard, wheel, pinch, API, reset); null zoom = the full extent.

Event name: zoomChange. Names are case-sensitive. Read the payload from detail on CustomEvent<CartesianZoomChangeEventDetail>.

chart.addEventListener('zoomChange', event => {
  console.log(event.detail); // CartesianZoomChangeEventDetail
});

• CartesianZoomChangeEventDetail

  Type definition

getDataTable

Current normalized table, including the retained stream; independent of GPU availability.

getDataTable(): Promise<ChartDataTable>

Return type: Promise<ChartDataTable>. Call the method after element registration and await its Promise result.

• ChartDataTable

  Type definition

redraw

Redraw the chart using its current data and options. Inspect the rendered result after the returned Promise resolves.

redraw(): Promise<SpectrogramRenderResult>

Return type: Promise<SpectrogramRenderResult>. Call the method after element registration and await its Promise result.

• SpectrogramRenderResult

  Type definition

getActiveTier

An asynchronous method. Check the argument and return types below.

getActiveTier(): Promise<SpectrogramEngineTier>

Return type: Promise<SpectrogramEngineTier>. Call the method after element registration and await its Promise result.

• SpectrogramEngineTier

  Type definition

getUnavailableReason

The reason the renderer cannot run (undefined while it runs).

getUnavailableReason(): Promise<string | undefined>

Return type: Promise<string | undefined>. Call the method after element registration and await its Promise result.

setData

Replace the bar set.

setData(data: SpectrogramInput): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

• SpectrogramInput

  Type definition

appendFrame

An asynchronous method. Check the argument and return types below.

appendFrame(frame: SpectrogramFrame): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

• SpectrogramFrame

  Type definition

appendBatch

Append multiple values to the stream. Check the argument type and the licensing requirements for streaming.

appendBatch(frames: ReadonlyArray<SpectrogramFrame>): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

• SpectrogramFrame

  Type definition

shift

Drop the count oldest frames — the data frames too (they fold into the internal source on the first shift as on the first append). (carry-over C8) — shift(n) drops the n oldest frames on screen. With an internal source the recording is folded into it (it shifts them itself); under an EXTERNAL source the recording's leading frames go first (before the source lost its frames while the recording's old frames came back into the window), then the source.

shift(count: number): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

replace

Swap the streamed set (replace([]) clears it); the base values never leave. Without chart.streaming the dies upsert into the base like a batch (quietly: no appended, no binChanged, as a ring replace).

replace(frames: ReadonlyArray<SpectrogramFrame>): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

• SpectrogramFrame

  Type definition

getStreamSource

The stream session's source (Chart Pro): like the stream methods it waits for a license still being confirmed.

getStreamSource(): Promise<SpectrogramStreamSource | undefined>

Return type: Promise<SpectrogramStreamSource | undefined>. Call the method after element registration and await its Promise result.

• SpectrogramStreamSource

  Type definition

setAnimation

An asynchronous method. Check the argument and return types below.

setAnimation(options: { duration?: number; easing?: SpectrogramEasing; enabled?: boolean; type?: SpectrogramAnimationType }): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

• SpectrogramEasing

  Type definition

• SpectrogramAnimationType

  Type definition

pauseAnimation

Pause the current animation.

pauseAnimation(): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

resumeAnimation

Resume a paused animation.

resumeAnimation(): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

replayAnimation

Replay the initial sweep from min → value(s). No-op when animation is off / reduced.

replayAnimation(): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

hitTest

The cell under host-relative CSS coordinates, or null.

hitTest(cssX: number, cssY: number): Promise<SpectrogramPointEventDetail | null>

Return type: Promise<SpectrogramPointEventDetail | null>. Call the method after element registration and await its Promise result.

• SpectrogramPointEventDetail

  Type definition

showTooltipAtCell

open the tooltip on a cell (frame / bin), honouring the tooltip input; null when the tooltip is off or the cell is outside.

showTooltipAtCell(frame: number, bin: number): Promise<CartesianTooltipEventDetail | null>

Return type: Promise<CartesianTooltipEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianTooltipEventDetail

  Type definition

showTooltipAtIndex

open the tooltip on a cell by its index (frame * bins + bin; the facade's showTooltipAtPoint).

showTooltipAtIndex(index: number): Promise<CartesianTooltipEventDetail | null>

Return type: Promise<CartesianTooltipEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianTooltipEventDetail

  Type definition

hideTooltip

Close the currently visible tooltip.

hideTooltip(): Promise<void>

Return type: Promise<void>. Call the method after element registration and await its Promise result.

focusCellAt

move the keyboard focus ring to a cell and announce it (null outside the grid).

focusCellAt(frame: number, bin: number): Promise<SpectrogramPointEventDetail | null>

Return type: Promise<SpectrogramPointEventDetail | null>. Call the method after element registration and await its Promise result.

• SpectrogramPointEventDetail

  Type definition

getValue

The dB value of a cell (null when empty or outside the grid).

getValue(frame: number, bin: number): Promise<number | null>

Return type: Promise<number | null>. Call the method after element registration and await its Promise result.

getValueExtent

The dB extent of the plane (min / max over the finite cells).

getValueExtent(): Promise<SpectrogramValueExtent | null>

Return type: Promise<SpectrogramValueExtent | null>. Call the method after element registration and await its Promise result.

• SpectrogramValueExtent

  Type definition

getGridSize

Columns × rows of the current grid.

getGridSize(): Promise<{ frames: number; bins: number; cells: number; dropped: number }>

Return type: Promise<{ frames: number; bins: number; cells: number; dropped: number }>. Call the method after element registration and await its Promise result.

getRanges

The time and frequency ranges the plane spans.

getRanges(): Promise<SpectrogramRanges>

Return type: Promise<SpectrogramRanges>. Call the method after element registration and await its Promise result.

• SpectrogramRanges

  Type definition

appendSamples

feed raw samples: every completed window becomes a frame (appended through the stream); the rest waits.

appendSamples(samples: ArrayLike<number>): Promise<SpectrogramAppendSamplesResult>

Return type: Promise<SpectrogramAppendSamplesResult>. Call the method after element registration and await its Promise result.

• SpectrogramAppendSamplesResult

  Type definition

getFftInfo

the FFT pipeline's resolved parameters (bins, bin width, frame seconds, the window's coherent gain).

getFftInfo(): Promise<SpectrogramFftInfo>

Return type: Promise<SpectrogramFftInfo>. Call the method after element registration and await its Promise result.

• SpectrogramFftInfo

  Type definition

setVisualMap

Bind (or clear with null) a visual-map snapshot; it wins over the visualMap prop until the prop changes again.

setVisualMap(binding: VisualMapBinding | null): Promise<VisualMapBinding | null>

Return type: Promise<VisualMapBinding | null>. Call the method after element registration and await its Promise result.

• VisualMapBinding

  Type definition

getVisualMap

An asynchronous method. Check the argument and return types below.

getVisualMap(): Promise<VisualMapBinding | null>

Return type: Promise<VisualMapBinding | null>. Call the method after element registration and await its Promise result.

• VisualMapBinding

  Type definition

getVisualExtent

The extent of a dimension: value = dB, x = time (s), y = frequency (Hz), index = the cell indexes.

getVisualExtent(request?: VisualMapExtentRequest): Promise<VisualMapExtent | null>

Return type: Promise<VisualMapExtent | null>. Call the method after element registration and await its Promise result.

• VisualMapExtent

  Type definition

• VisualMapExtentRequest

  Type definition

zoomTo

Zoom to explicit windows in axis units: x (seconds) / y (Hz) as { min, max } or [min, max] (null clears that orientation).

zoomTo(request: CartesianZoomRequest): Promise<CartesianZoomChangeEventDetail | null>

Return type: Promise<CartesianZoomChangeEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianZoomChangeEventDetail

  Type definition

• CartesianZoomRequest

  Type definition

zoomBy

Scale the current windows by factor (< 1 zooms in) around anchorFraction (0..1, default centre).

zoomBy(factor: number, anchorFraction?: number): Promise<CartesianZoomChangeEventDetail | null>

Return type: Promise<CartesianZoomChangeEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianZoomChangeEventDetail

  Type definition

panBy

Slide the zoomed windows by axis units ({ x?: seconds, y?: Hz }); a no-op at the full extent.

panBy(delta: { x?: number; y?: number }): Promise<CartesianZoomChangeEventDetail | null>

Return type: Promise<CartesianZoomChangeEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianZoomChangeEventDetail

  Type definition

resetZoom

Reset the zoomed or panned range to the original data range.

resetZoom(): Promise<CartesianZoomChangeEventDetail | null>

Return type: Promise<CartesianZoomChangeEventDetail | null>. Call the method after element registration and await its Promise result.

• CartesianZoomChangeEventDetail

  Type definition

getZoom

Read the current zoom range. Check the return type's nullability and the range for each axis.

getZoom(): Promise<CartesianZoomState | null>

Return type: Promise<CartesianZoomState | null>. Call the method after element registration and await its Promise result.

• CartesianZoomState

  Type definition

getZoomExtent

The full extent (and key) of the primary — or the named — axes: the time span in seconds, the frequency span in Hz.

getZoomExtent(request?: CartesianZoomExtentRequest): Promise<CartesianZoomExtentDetail | null>

Return type: Promise<CartesianZoomExtentDetail | null>. Call the method after element registration and await its Promise result.

• CartesianZoomExtentDetail

  Type definition

• CartesianZoomExtentRequest

  Type definition

getEngineStatus

Requested engine vs what runs, and why (CHART-ADD-08): the decision for the current inputs, read without side effects (ProChartLicense.engineStatus); a renderer that failed at run time reports engine-unsupported.

getEngineStatus(): Promise<ChartEngineStatus>

Return type: Promise<ChartEngineStatus>. Call the method after element registration and await its Promise result.

• ChartEngineStatus

  Type definition