使用Java pdfbox将jpg文件插入到PDF文档中，只有1/4的图像显示在PDF文档中

Question

我正在尝试使用Java PDFBox库将宽度为1680，高度为1080的jpg文件插入PDF文档。我正在尝试在文档的20,20处插入图像，而PDF中仅显示图像的1/4。我需要将多个图像和每个图像插入一个单独的页面。这是我的代码，请告诉我我做错了什么？

import java.io.IOException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;

public class pdfAddingPages {

public static void main(String[] args) {
     //Creating PDF document object 
      PDDocument document = new PDDocument();


         PDPage Page1 = new PDPage();

         //Adding the blank page to the document
         document.addPage( Page1 );


    //Creating PDImageXObject object
    PDImageXObject pdImage = null;
    try {
        pdImage = PDImageXObject.createFromFile("C:/Test/image1680x1080.jpeg",document);
    } catch (IOException e4) {
        // TODO Auto-generated catch block
        e4.printStackTrace();
    }

      //creating the PDPageContentStream object
      PDPageContentStream contents;
    try {
        contents = new PDPageContentStream(document, Page1);
        contents.drawImage(pdImage, 20, 20);  // positon at 20,20
        //contents.drawImage(pdImage, 0, 0, 1638, 1080);

        contents.close();
        //int chartWidth = 1638;  //2000, 1900, 1800
            //int chartHeight = 1080 ;

    } catch (IOException e3) {
        // TODO Auto-generated catch block
        e3.printStackTrace();
    }
    //Saving the document
    try {
        document.save("C:/Test/my_doc_image.pdf");
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
      System.out.println("PDF created");

      //Closing the document
      try {
        document.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

}

Answer 1

要以较小的尺寸绘制图像，请使用比例因子：

contents.drawImage(pdImage, 20, 20, pdImage.getWidth() / 4, pdImage.getHeight() / 4);