export interface CaptchaHollowOptions {
    ctx: CanvasRenderingContext2D;
    /**
     * The x coordinate of slide target center
     */
    x: number;
    /**
     * The y coordinate of slide target center
     */
    y: number;
    /**
     * Current canvas width
     */
    width: number;
    /**
     * Current canvas height
     */
    height: number;
}
/**
 * Specify the react of the hollow's shape
 */
export declare type CaptchaHollowResult = [
    x: number,
    y: number,
    width: number,
    height: number
];
export declare type CaptchaHollowProcess = (options: CaptchaHollowOptions) => CaptchaHollowResult;
export declare type CaptchaHollowType = 'square' | 'puzzle' | 'shield' | 'heart';
export declare const squarePath: CaptchaHollowProcess;
export declare const puzzlePath: CaptchaHollowProcess;
export declare const shieldPath: CaptchaHollowProcess;
export declare const heartPath: CaptchaHollowProcess;