import { _PdfBaseStream } from './base-stream';
import { _PdfDecodeStream } from './decode-stream';
import { _Cipher } from './security/encryptors/cipher';
/**
 * Decrypting stream that reads encrypted data from an underlying stream and
 * exposes the decrypted bytes.
 *
 * @private
 */
export declare class _PdfDecryptStream extends _PdfDecodeStream {
    /**
     * Size of chunks read and decrypted from the underlying stream.
     *
     * @private
     */
    readonly _chunkSize: number;
    /**
     * True after the first chunk has been read and initialized.
     *
     * @private
     */
    _initialized: boolean;
    /**
     * Buffer holding the next chunk read ahead from the underlying stream.
     *
     * @private
     */
    _nextChunk: Uint8Array;
    /**
     * Cipher instance used to decrypt blocks read from the underlying stream.
     *
     * @private
     */
    _cipher: _Cipher;
    constructor(stream: _PdfBaseStream, maybeLength: number, cipher: _Cipher);
    readBlock(): void;
}