/**
 * Laplacian of gaussian filter
 */
export default class LoG {
    /**
     * @param {number} th Threshold
     */
    constructor(th: number);
    _threshold: number;
    _k: number;
    _s: number;
    _convolute(x: any, kernel: any): any[][];
    /**
     * Returns predicted edge flags.
     * @param {Array<Array<number>>} x Training data
     * @returns {Array<Array<boolean>>} Predicted values. `true` if a pixel is edge.
     */
    predict(x: Array<Array<number>>): Array<Array<boolean>>;
}