import BN from 'bn.js';
import { PrivateKey } from './key_private';
import { PublicKey } from './key_public';
export declare class Signature {
    r: BN;
    s: BN;
    i: number;
    constructor(r: BN, s: BN, i: number);
    static fromBuffer(buffer: Buffer): Signature;
    toBuffer(): Buffer;
    static signBuffer(buf: Buffer, private_key: PrivateKey | string): Signature;
    static signBufferSha256(buf_sha256: Buffer, private_key: PrivateKey | string): Signature;
    static isCanonical(r: Buffer, s: Buffer): boolean;
    static sign(string: string, private_key: PrivateKey | string): Signature;
    verifyBuffer(buf: Buffer, public_key: PublicKey): boolean;
    verifyHash(hash: Buffer, public_key: PublicKey): boolean;
    static fromHex(hex: string): Signature;
    toHex(): string;
}