如何在java中将PDF (只包含tiff图像)转换为JPG图像

import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;

File pdfFile = new File("path/to/pdf/file.pdf");
PDDocument document = PDDocument.load(pdfFile);

PDFRenderer renderer = new PDFRenderer(document);
int numPages = document.getNumberOfPages();

for (int i = 0; i < numPages; i++) {
    BufferedImage image = renderer.renderImageWithDPI(i, 300); // 设置图像分辨率为300dpi
    ImageIO.write(image, "jpg", new File("path/to/output/image" + i + ".jpg"));
}