import type { CropArea } from '../typings';
export interface ImagePosition {
    offsetX: number;
    offsetY: number;
}
export interface BaseDisplaySize {
    width: number;
    height: number;
}
export interface InitialCropAreaResult {
    baseDisplayHeight: number;
    baseDisplayWidth: number;
    cropArea: CropArea;
    imagePosition: ImagePosition;
}
/**
 * Calculate base scale for image to cover canvas (both dimensions).
 */
export declare function getBaseScale(rect: DOMRect, img: HTMLImageElement): number;
/**
 * Calculate base display size of image.
 */
export declare function getBaseDisplaySize(rect: DOMRect, img: HTMLImageElement): BaseDisplaySize;
/**
 * Calculate initial crop area and image position.
 */
export declare function calculateInitialCropArea(img: HTMLImageElement, rect: DOMRect, aspectRatio?: number): InitialCropAreaResult;
/**
 * Constrain image position to ensure it covers crop area.
 */
export declare function constrainImagePosition(newOffsetX: number, newOffsetY: number, displayWidth: number, displayHeight: number, cropArea: CropArea): ImagePosition;
/**
 * Check if two crop areas are similar (within threshold).
 */
export declare function isCropAreaSimilar(a: CropArea | null, b: CropArea | null, threshold?: number): boolean;
/**
 * Check if two image positions are similar (within threshold).
 */
export declare function isImagePositionSimilar(a: ImagePosition | null, b: ImagePosition | null, threshold?: number): boolean;