Load document from FTP

using (Annotator annotator = new Annotator(GetFileFromFtp("sample.pdf")))
{
	AreaAnnotation area = new AreaAnnotation()
	{
		Box = new Rectangle(100, 100, 100, 100),
		BackgroundColor = 65535,
	};
	annotator.Add(area);
	annotator.Save("result.pdf");
}

private static Stream GetFileFromFtp(string filePath)
{
	Uri uri = new Uri(filePath);
	FtpWebRequest request = CreateRequest(uri);
	using (WebResponse response = request.GetResponse())
                return GetFileStream(response);
}

private static FtpWebRequest CreateRequest(Uri uri)
{
	FtpWebRequest request = (FtpWebRequest)WebRequest.Create(uri);
	request.Method = WebRequestMethods.Ftp.DownloadFile;
		return request;
}

private static Stream GetFileStream(WebResponse response)
{
	MemoryStream fileStream = new MemoryStream();
	using (Stream responseStream = response.GetResponseStream())
		responseStream.CopyTo(fileStream);
		fileStream.Position = 0;
		return fileStream;
}