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文章目录- 前言
- 一、依赖JAR
- 二、代码工具类
- 三、main测试
- 总结
前言 ## Java实现pdf转图片 ** 置顶@@@
提示：以下是本篇文章正文内容，下面案例可供参考
一、依赖JAR
com.itextpdf
itextpdf
5.4.2
org.apache.pdfbox
pdfbox
2.0.15
org.apache.pdfbox
fontbox
2.0.15
二、代码工具类
package com.example.demo.utils;
import com.google.common.collect.Maps;
import org.apache.pdfbox.pdmodel.PDdocument;
import org.apache.pdfbox.rendering.ImageType;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
public class PDFToImage {
private static final Logger LOGGER = LoggerFactory.getLogger(PDFToImage.class);
public static List pdfToImagePaths(String filePath, String savePath, String subStr) {
List list = new ArrayList<>();
String fileDirectory = filePath.substring(0, filePath.lastIndexOf("."));
String imagePath;
File file = new File(filePath);
try {
File f = new File(fileDirectory);
if (!f.exists()) {
f.mkdir();
}
PDdocument doc = PDdocument.load(file);
PDFRenderer renderer = new PDFRenderer(doc);
int pageCount = doc.getNumberOfPages();
for (int i = 0; i < pageCount; i++) {
//方式2,第二个参数是设置缩放比(即像素) 第二个参数越大生成图片分辨率越高，转换时间也就越长
BufferedImage image = renderer.renderImage(i, 1.25f);
imagePath = savePath + File.separator + subStr + "-" + i + ".jpg";
ImageIO.write(image, "PNG", new File(imagePath));
list.add(imagePath);
}
} catch (Exception e) {
LOGGER.error(e.getMessage());
}
return list;
}
public static void pdfMultiImage(String pdfFile, String outpath) {
try {
ArrayList piclist = new ArrayList<>();
File file = new File(pdfFile);
PDdocument doc = PDdocument.load(file);
//pdfbox 1.8
//pdfbox2.0以后
int pages = doc.getNumberOfPages();
//分辨率
int dpi = 200;
for (int i = 0; i < pages; i++) {
BufferedImage image = new PDFRenderer(doc).renderImageWithDPI(i, dpi, ImageType.RGB);
piclist.add(image);
}
yPic(piclist, outpath);
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
private static void pdf2multiImage(String pdfFile, String outpath, int maxPage) {
//try {
// InputStream is = new FileInputStream(pdfFile);
// PDdocument pdf = PDdocument.load(is, true);
// List pages = pdf.getdocumentCatalog().getAllPages();
// List piclist = new ArrayList();
// // pdf中实际的页数
// int actSize = pages.size();
// if (actSize < maxPage) {
// maxPage = actSize;
// }
// for (int i = 0; i < maxPage; i++) {
// piclist.add(pages.get(i).convertToImage());
// }
// yPic(piclist, outpath);
// is.close();
//} catch (IOException e) {
// e.printStackTrace();
//}
}
public static void yPic(List piclist, String outPath) {
if (piclist == null || piclist.size() <= 0) {
LOGGER.error("图片数组为空!");
return;
}
try {
// 总高度,总宽度 ,临时的高度 , 或保存偏移高度,临时的高度，主要保存每个高度,图片的数量
int height = 0, width = 0, _height, __height, picNum = piclist.size();
// 保存每个文件的高度
int[] heightArray = new int[picNum];
// 保存图片流
BufferedImage buffer;
// 保存所有的图片的RGB
List imgRgb = new ArrayList<>();
// 保存一张图片中的RGB数据
int[] _imgRGB;
for (int i = 0; i < picNum; i++) {
buffer = piclist.get(i);
// 图片高度
heightArray[i] = _height = buffer.getHeight();
if (i == 0) {
// 图片宽度
width = buffer.getWidth();
}
// 获取总高度
height += _height;
// 从图片中读取RGB
_imgRGB = new int[width * _height];
_imgRGB = buffer.getRGB(0, 0, width, _height, _imgRGB, 0, width);
imgRgb.add(_imgRGB);
}
// 设置偏移高度为0
_height = 0;
// 生成新图片
BufferedImage imageResult = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
for (int i = 0; i < picNum; i++) {
__height = heightArray[i];
// 计算偏移高度
if (i != 0) {
_height += __height;
}
imageResult.setRGB(0, _height, width, __height, imgRgb.get(i), 0, width);
}
File outFile = new File(outPath);
// 写图片
ImageIO.write(imageResult, "jpg", outFile);
} catch (Exception e) {
LOGGER.error(e.getMessage());
}
}
public static ArrayList getDirPathFiles(String path) {
ArrayList files = new ArrayList<>();
Map map = Maps.newHashMap();
File file = new File(path);
File[] tempList = file.listFiles();
for (int i = 0; i < Objects.requireNonNull(tempList).length; i++) {
if (tempList[i].isFile()) {
files.add(tempList[i].toString());
map.put(tempList[i].getAbsolutePath(), tempList[i].getName());
}
}
return files;
}
}
三、main测试
public static void main(String[] args) {
//ArrayList files = new ArrayList<>();
//Map map = Maps.newHashMap();
ArrayList list = getDirPathFiles("D:\pdfile");
//File file = new File("D:\pdfile");
//File[] tempList = file.listFiles();
//for (int i = 0; i < Objects.requireNonNull(tempList).length; i++) {
// if (tempList[i].isFile()) {
// files.add(tempList[i].toString());
// map.put(tempList[i].getAbsolutePath(), tempList[i].getName().substring(0, tempList[i].getName().lastIndexOf(".")));
// }
//}
//for (int i = 0; i < files.size(); i++) {
// try {
// String filePath = files.get(i);
// List stringList = pdfToImagePaths(filePath, "D:\pacsFile", map.get(filePath) + "-" + i + "");
// System.out.println(stringList);
// } catch (Exception e) {
// e.printStackTrace();
// }
//}
pdfMultiImage("D:\pdfile\PdfReport.pdf", "D:\pacsFile\pdf.jpg");
}
总结
pdfbox 1.6/1.8实现的有稍微差别 注意！！！！
