PdfReader reader = new PdfReader(src);
        PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(targetPdf));
        stamper.setRotateContents(false);
        List<PdfCleanUpLocation> cleanUpLocations = new ArrayList<PdfCleanUpLocation>();
        Rectangle rectangle = new Rectangle(400, 600, 500, 650);
        cleanUpLocations.add(new PdfCleanUpLocation(1, rectangle, BaseColor.BLACK));
        PdfCleanUpProcessor cleaner = new PdfCleanUpProcessor(cleanUpLocations, stamper);
        cleaner.cleanUp();
        stamper.close();
        reader.close()