/// <reference types="node" />
/// <reference types="node" />
import * as zlib from "zlib";
import stream from "node:stream";
import { Header } from "./header";
import { Filter, FilterOrder } from "./filter";
import { ResponseContext } from "./response";
import { RequestContext } from "./request-context";
export declare abstract class Encoding extends Header implements Filter {
    protected constructor(format?: string, _qualityValue?: number);
    filter(_: RequestContext, responseContext?: ResponseContext): void;
    order(): FilterOrder;
    abstract getCompressor(): stream.Readable;
}
export declare class GzipEncoding extends Encoding {
    private readonly _zlibOptions?;
    constructor(zlibOptions?: zlib.ZlibOptions);
    getCompressor(): stream.Readable;
}