/**
 * Return 1/x where x is perceptible (not unlimited or infinitesimal).
 *
 * @param x
 *
 * @see https://imagemagick.org/api/MagickCore/pixel-accessor_8h_source.html#l00234 PerceptibleReciprocal()
 * at ImageMagick source.
 */
export declare function perceptibleReciprocal(x: number): number;