import { CoseProtectedHeaders, CoseUnprotectedHeaders } from "../cose";
/**
 * Get a header value from the COSE headers.
 *
 * If both protected and unprotected headers give the header, the
 * function will return the kid given in the  protected header
 *
 *
 * @param protectedHeaders
 * @param unprotectedHeaders
 * @param headerKey
 */
export declare const extractHeader: (protectedHeaders: CoseProtectedHeaders, unprotectedHeaders: CoseUnprotectedHeaders, headerKey: number) => unknown;