/** A palette measured off a real display; the same tuples dither.nim holds. */
type Rgb = readonly [number, number, number];
/** The panel kinds a preview can be shown through. */
export type PanelPaletteKey = 'spectra6' | 'sevenColor' | 'fourColor' | 'blackWhiteRed' | 'blackWhiteYellow' | 'sixteenGray' | 'fourGray' | 'blackWhite';
type PanelPalette = {
    readonly key: PanelPaletteKey;
    readonly label: string;
    readonly colors: readonly Rgb[];
} | {
    readonly key: PanelPaletteKey;
    readonly label: string;
    readonly grayLevels: number;
};
/** In the order the picker offers them: colour panels first, then greys. */
export declare const panelPalettes: readonly PanelPalette[];
export declare function panelPaletteFor(key: string | null | undefined): PanelPalette | null;
/**
 * Re-colours an RGBA frame in place the way `panel` would show it. Alpha is
 * left alone; the runtime hands us opaque frames, the same picture the
 * driver dithers.
 */
export declare function ditherFrame(data: Uint8ClampedArray, width: number, height: number, panel: PanelPalette): void;
export {};