@SuppressWarnings("unchecked")
public PDFHighlightImage call() throws Exception {
PdfDecoder pdf = new PdfDecoder();
PdfDecoder.setFontReplacements(pdf);
pdf.openPdfFile(pdfFile.toString());
pdf.setPageParameters(zoom, pageNum);
pdf.decodePage(pageNum);
BufferedImage pdfImage = pdf.getPageAsImage(pageNum);
PdfGroupingAlgorithms grouping = pdf.getGroupingObject();
PdfPageData page = pdf.getPdfPageData();