import type { CanvasDocument } from './canvasDocument.js';
export type CanvasExportFormat = 'png' | 'jpeg' | 'json';
/** Parse CSS color alpha; `transparent` / missing → 0. */
export declare function backgroundAlpha(color: string | undefined): number;
/** Renders the artboard at 1:1 document pixels into an offscreen canvas. */
export declare function renderCanvasDocument(doc: CanvasDocument, opts?: {
    opaqueBackground?: boolean;
}): Promise<HTMLCanvasElement>;
export declare function exportCanvasBlob(doc: CanvasDocument, format?: 'png' | 'jpeg', quality?: number): Promise<Blob>;
export declare function downloadBlob(blob: Blob, filename: string): void;