public PdfManipulator(OutputStream os, InputStream in, float[] rect) throws IOException {
		this.pdfreader = new PdfReader(in);
		this.originSize = pdfreader.getPageSize(1);
		if (rect == null || rect.length != 2) {
			document = new Document(PageSize.A4, 36f, 36f, 36f, 36f);
		} else {
			this.rectangle = new Rectangle(rect[0], rect[1]);
			document = new Document(rectangle, 36f, 36f, 36f, 36f);
		}
		try {
			pdfwriter = PdfWriter.getInstance(document, os);
		} catch (DocumentException e) {
			e.printStackTrace();
		}
		document.open();
	}