/**
 * ImageDataHelper
 *
 * Utility class for working with image data, including raster and SVG sources.
 * Provides methods to render images (data URLs, inline SVG strings, external URLs) into a canvas
 * and to convert them into Uint8Array (PNG bytes by default).
 *
 * Features:
 * - Supports raster and SVG input
 * - Handles inline SVG strings, data:image/svg+xml URLs, and external SVG URLs
 * - Preserves aspect ratio by default, can disable if needed
 * - Produces crisp rendering for SVG when resizing
 * - Backward-compatible: does not modify existing functions in your code
 */
export declare class ImageDataHelper {
    /**
     * Convert a canvas to Uint8Array (PNG by default).
     */
    static canvasToUint8Array(canvas: HTMLCanvasElement, type?: string, quality?: number): Promise<Uint8Array>;
    /**
     * Detect whether input is an SVG (data URL or inline string).
     */
    private static isSvgSource;
    /**
     * Decode an SVG from a data: URL or return raw SVG string.
     */
    private static decodeSvgStringIfNeeded;
    /**
     * Extract intrinsic width/height or viewBox from SVG text.
     */
    private static getSvgIntrinsicSize;
    /**
     * Inject/replace width/height and preserveAspectRatio attributes in SVG text.
     */
    private static setSvgSize;
    /**
     * Render any image (raster or SVG) into a canvas of the requested size.
     * - Works with inline SVG, data:image/svg+xml, and external SVG URLs (fetched if same-origin or CORS allowed).
     * - Preserves aspect ratio by default.
     */
    static imageDataToCanvasWithSize(src: string, targetWidth?: number, targetHeight?: number, keepAspectRatio?: boolean): Promise<HTMLCanvasElement>;
    /**
     * High-level helper:
     * Render the provided image into a canvas of the given size and return the PNG bytes as Uint8Array.
     *
     * @param src - raster or SVG source (data URL, inline string, external URL)
     * @param targetWidth - output width in pixels (optional)
     * @param targetHeight - output height in pixels (optional)
     * @param keepAspectRatio - preserve aspect ratio (default: true)
     */
    static dataUrlToUint8ArrayWithSize(src: string, targetWidth?: number, targetHeight?: number, keepAspectRatio?: boolean): Promise<Uint8Array>;
}