PDFBox-将2个纵向页面合并到单个并排横向页面上

Question

我正在尝试编写pdf转换，它将采用包含1-up纵向页面的pdf，并创建一个新文档，但是每2页合并为一个2-up横向页面

即。

下面的代码将内容缩小50％，但是我无法弄清楚如何使新页面成为横向，同时将另一页面作为纵向注入，并注入到中心的左上角和右边

public static void main(String[] args) throws IOException, DocumentException, COSVisitorException {
    scalePages("c:/pdf/in.pdf", "c:/pdf/out" + new Date().getTime() + ".pdf", 0.50f);
}

public static void scalePages(String inFile, String outFile, float scale ) throws IOException, COSVisitorException {      
    PDDocument doc1 = null;      
    try {          
        doc1 = PDDocument.load( inFile );  
        List allPages = doc1.getDocumentCatalog().getAllPages();          
        for( int i=0; i<allPages.size(); i++ ) {              
            PDPage page1 = (PDPage)allPages.get(i ); 
            PDRectangle mediaBox = page1.getMediaBox();

            float oldX = mediaBox.getUpperRightX();
            float newX = oldX * scale;

            float oldY = mediaBox.getUpperRightY();
            float newY = oldY * scale;

            mediaBox.setUpperRightX(newX); 
            mediaBox.setUpperRightY(newY);
            PDFStreamParser parser = new PDFStreamParser(page1.getContents());              
            parser.parse();
            List tokens = parser.getTokens();              
            tokens.add(0,new COSFloat(scale));              
            tokens.add(1,new COSInteger(0));
            tokens.add(2,new COSInteger(0));
            tokens.add(3,new COSFloat(scale));             
            tokens.add(4,new COSInteger(0));
            tokens.add(5,new COSInteger(0));
            tokens.add(6,PDFOperator.getOperator("cm"));
            PDStream newContents = new PDStream( doc1 );              
            ContentStreamWriter writer = new ContentStreamWriter( newContents.createOutputStream() );
            writer.writeTokens( tokens );              
            newContents.addCompression();
            page1.setContents(newContents);
            //page1.setRotation(90);
            mediaBox.setUpperRightX(oldX);
            mediaBox.setUpperRightY(oldY);
        }          
        doc1.save( outFile );
    } finally {          
        if( doc1 != null )   {
            doc1.close();    
        }      
    }  
}

所以结果如下

任何指针将不胜感激

Answer 1

这是一个示例，该示例并排“缝合”两个一页PDF，并使用PDFBox将结果保存到新文件中。请享用！

function void generateSideBySidePDF() {
    File pdf1File = new File(FILE1_PATH);
    File pdf2File = new File(FILE2_PATH);
    File outPdfFile = new File(OUTFILE_PATH);
    PDDocument pdf1 = null;
    PDDocument pdf2 = null;
    PDDocument outPdf = null;
    try {
        pdf1 = PDDocument.load(pdf1File);
        pdf2 = PDDocument.load(pdf2File);
        outPdf = new PDDocument();

        // Create output PDF frame
        PDRectangle pdf1Frame = pdf1.getPage(0).getCropBox();
        PDRectangle pdf2Frame = pdf2.getPage(0).getCropBox();
        PDRectangle outPdfFrame = new PDRectangle(pdf1Frame.getWidth()+pdf2Frame.getWidth(), Math.max(pdf1Frame.getHeight(), pdf2Frame.getHeight()));

        // Create output page with calculated frame and add it to the document
        COSDictionary dict = new COSDictionary();
        dict.setItem(COSName.TYPE, COSName.PAGE);
        dict.setItem(COSName.MEDIA_BOX, outPdfFrame);
        dict.setItem(COSName.CROP_BOX, outPdfFrame);
        dict.setItem(COSName.ART_BOX, outPdfFrame);
        PDPage outPdfPage = new PDPage(dict);
        outPdf.addPage(outPdfPage);

        // Source PDF pages has to be imported as form XObjects to be able to insert them at a specific point in the output page
        LayerUtility layerUtility = new LayerUtility(outPdf);
        PDFormXObject formPdf1 = layerUtility.importPageAsForm(pdf1, 0);
        PDFormXObject formPdf2 = layerUtility.importPageAsForm(pdf2, 0);

        // Add form objects to output page
        AffineTransform afLeft = new AffineTransform();
        layerUtility.appendFormAsLayer(outPdfPage, formPdf1, afLeft, "left");
        AffineTransform afRight = AffineTransform.getTranslateInstance(pdf1Frame.getWidth(), 0.0);
        layerUtility.appendFormAsLayer(outPdfPage, formPdf2, afRight, "right");

        outPdf.save(outPdfFile);
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            if (pdf1 != null) pdf1.close();
            if (pdf2 != null) pdf2.close();
            if (outPdf != null) outPdf.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}