import { type VisualThreshold } from './thresholds.js';
export type ComparePngImagesInput = {
    expectedPath: string;
    actualPath: string;
    diffPath?: string;
    threshold?: VisualThreshold;
    strict?: boolean;
};
export type ImageDimensions = {
    width: number;
    height: number;
};
export type VisualDiffCategory = 'dimension-mismatch' | 'broad-framing-or-layout' | 'localized-change' | 'sparse-text-or-antialiasing' | 'color-or-token-drift';
export type VisualDiffBoundingBox = {
    x: number;
    y: number;
    width: number;
    height: number;
};
export type VisualDiffDiagnostics = {
    summary: string;
    categories: VisualDiffCategory[];
    boundingBox?: VisualDiffBoundingBox;
    changedAreaRatio?: number;
    density?: number;
    colorDelta?: {
        average: number;
        max: number;
    };
    distribution?: {
        horizontal: {
            left: number;
            center: number;
            right: number;
        };
        vertical: {
            top: number;
            middle: number;
            bottom: number;
        };
    };
    likelyCauses: string[];
};
export type ImageDiffResult = {
    status: 'pass' | 'warn' | 'fail';
    classification: 'visual-match' | 'visual-diff' | 'visual-dimension-mismatch';
    width?: number;
    height?: number;
    expected: ImageDimensions;
    actual: ImageDimensions;
    diffPixels: number;
    diffRatio: number;
    dimensionMismatch: boolean;
    threshold?: VisualThreshold;
    thresholdReason?: 'maxDiffPixels' | 'maxDiffPixelRatio';
    diffPath?: string;
    diagnostics?: VisualDiffDiagnostics;
};
export declare function comparePngImages(input: ComparePngImagesInput): Promise<ImageDiffResult>;
export declare function formatVisualDiagnosticsDetails(diagnostics: VisualDiffDiagnostics | undefined): string | undefined;