/**
 * Canvas utilities - creates and styles the glow canvas.
 * Like YouTube's web player glow (minus the thumbnail spritesheet service).
 *
 * @module lib/canvas
 * @internal
 */
import type { NormalizedGlowOptions } from '../types';
/**
 * Creates the main glow canvas.
 *
 * @param options - Glow styling options.
 * @returns Canvas ready to add to DOM.
 *
 * @internal
 */
export declare function createGlowCanvas(options: NormalizedGlowOptions): HTMLCanvasElement;
/**
 * Creates a temp canvas for processing frames.
 *
 * @returns Temp canvas.
 *
 * @internal
 */
export declare function createTempCanvas(): HTMLCanvasElement;
/**
 * Gets 2D context from canvas with optimized settings.
 *
 * @param canvas - Canvas to get context from.
 * @param canvasName - Name for error messages.
 * @returns The 2D context.
 * @throws {Error} If 2D context unavailable.
 *
 * @internal
 */
export declare function getCanvasContext(canvas: HTMLCanvasElement, canvasName?: string): CanvasRenderingContext2D;
/**
 * Styles the canvas with blur, brightness, etc.
 *
 * @param canvas - Canvas to style.
 * @param options - Glow options.
 *
 * @internal
 */
export declare function applyCanvasStyles(canvas: HTMLCanvasElement, options: NormalizedGlowOptions): void;
/**
 * Updates canvas filters when options change.
 *
 * @param canvas - Canvas to update.
 * @param options - New glow options.
 *
 * @internal
 */
export declare function updateCanvasFilterStyles(canvas: HTMLCanvasElement, options: NormalizedGlowOptions): void;
/**
 * Makes sure parent has positioning (sets to relative if needed).
 *
 * @param parent - Parent element to fix.
 *
 * @internal
 */
export declare function ensureParentPositioning(parent: HTMLElement): void;