/// <reference types="node" />
import { Transform, TransformCallback, TransformOptions } from 'stream';
import { RawData } from '../interfaces';
export interface FilterTransformOptions extends TransformOptions {
    filterFn: (data: RawData) => boolean;
}
export declare class FilterTransform extends Transform {
    private opts;
    constructor(opts?: FilterTransformOptions);
    _transform(chunk: Buffer, encoding: string, callback: TransformCallback): void;
    _flush(callback: TransformCallback): void;
}