/// <reference types="node" />
import { PNGDiffer, DiffResult } from '../interfaces/png-differ';
export interface Color {
    r: number;
    g: number;
    b: number;
}
export interface PixelDifferOptions {
    /**
     * The color used to mark different pixels.
     */
    diffColor?: Color;
    /**
     * A number between `0` and `1` representing the max difference in %
     * between 2 pixels to be considered identical.
     *
     * @example
     * `0` means the pixel need to be identical.
     *
     * @example
     * `1` means two completely different images will be identical. If the
     * images have different dimension then the comparison will fail.
     *
     * @example
     * `0.1` means black (`#000`) and 90% gray (`#0a0a0a`) will be identical.
     */
    threshold?: number;
}
/**
 * Compare screenshots pixel by pixel using
 * [pixelmatch](https://github.com/mapbox/pixelmatch).
 *
 * Images with different dimensions will always fail comparison and a diff
 * indicating the extra region will be returned. The images will be overlaid
 * starting from the top left corner and then compared. All of the pixels that
 * are outside of the intersection will be considered different, no matter the
 * {@link PixelDifferOptions.threshold | threshold}.
 *
 * ![pixel-differ-explanation](media://pixel-differ-explanation.png)
 *
 * See the examples below to understand how images with different sizes will be
 * compared.
 *
 * ![pixel-differ-examples](media://pixel-differ-examples.png)
 */
export declare class PixelDiffer implements PNGDiffer {
    private readonly diffColor;
    private readonly threshold;
    /**
     * @param __namedParameters {@link PixelDifferOptions}
     */
    constructor({ diffColor, threshold, }?: PixelDifferOptions);
    compare: (expected: Buffer, actual: Buffer) => Promise<DiffResult>;
}