/// <reference types="node" />
import { Transform } from 'stream';
export declare class EncryptTransform extends Transform {
    private cryptoService;
    private hash;
    private prev;
    constructor(cryptoService: any, hash: string, options?: any);
    _transform(chunk: any, encoding: string, callback: (error?: Error | null) => void): void;
    _flush(callback: (error?: Error | null) => void): void;
}