将pdf转化为图片的方法

package com.pdf.change2img;import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.springframework.util.Base64Utils;import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;/*** @author * @Description* @Date 2021/10/22 下午9:19*/
public class PdfToImageUtil {/*** dpi越大转换后越清晰，相对转换速度越慢*/private static final Integer DPI = 100;/*** 转换后的图片类型*/private static final String IMG_TYPE = "png";/*** PDF转图片** @param fileContent PDF文件的二进制流* @return 图片文件的二进制流*/public static List<byte[]> pdfToImage(byte[] fileContent) throws IOException {List<byte[]> result = new ArrayList<>();try (PDDocument document = PDDocument.load(fileContent)) {PDFRenderer renderer = new PDFRenderer(document);for (int i = 0; i < document.getNumberOfPages(); ++i) {BufferedImage bufferedImage = renderer.renderImageWithDPI(i, DPI);ByteArrayOutputStream out = new ByteArrayOutputStream();ImageIO.write(bufferedImage, IMG_TYPE, out);result.add(out.toByteArray());}}return result;}/**** @param base64PDF* @return* @throws IOException*/public static List<String> pdfToImage2(String base64PDF) throws IOException {List<String> result = new ArrayList<>();byte[] decodePDF = Base64Utils.decode(base64PDF.getBytes());try (PDDocument document = PDDocument.load(decodePDF)) {PDFRenderer renderer = new PDFRenderer(document);for (int i = 0; i < document.getNumberOfPages(); ++i) {BufferedImage bufferedImage = renderer.renderImageWithDPI(i, DPI);ByteArrayOutputStream out = new ByteArrayOutputStream();ImageIO.write(bufferedImage, IMG_TYPE, out);result.add(Base64Utils.encodeToString(out.toByteArray()));}}return result;}
}