JAVA怎么将PDF的base64转换成jpg的base64

发布网友发布时间：2022-04-21 15:26

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热心网友时间：2022-04-24 08:19

package com.aiait.base.util;

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 com.aiait.base.service.impl.base.SearchServiceImpl;

import org.apache.pdfbox.*;

import java.awt.image.BufferedImage;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.net.URL;

import java.text.DecimalFormat;

import java.util.Date;

import javax.imageio.ImageIO;

import org.apache.commons.lang3.StringUtils;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

public class PDFUtil {

// logger

private static final Logger lOGGER = LoggerFactory.getLogger(PDFUtil.class);

public static void main(String[] args) {

//pdfTojpg("C://Test//eClaimPDF//1//Others.pdf","C://Test//eClaimPDF//WrittenConfirmation.jpg");

Date timeDiffE = null;

Date timeDiffL = null;

timeDiffE = new Date();

base64PdfToJpg(pdfBase64);

timeDiffL = new Date();

lOGGER.info("base64PdfToJpg use time: " + getDiffTime(timeDiffL, timeDiffE) + "s");

}

private static String base64PdfToJpg(String base64Pdf) {

String jpg_base64 = null;

int pdfdpi = 400;

BASE64Decoder decoder = new BASE64Decoder();

byte[] pdf_bytes = null;

try {

pdf_bytes = decoder.decodeBuffer(base64Pdf);

} catch (IOException e1) {

e1.printStackTrace();

}

try (final PDDocument document = PDDocument.load(pdf_bytes)) {

int size = document.getNumberOfPages();

/*图像合并使用参数*/

// 定义宽度

int width = 0;

// 保存一张图片中的RGB数据

int[] singleImgRGB;

// 定义高度，后面用于叠加

int shiftHeight = 0;

//保存每张图片的像素值

BufferedImage imageResult = null;

// 利用PdfBox生成图像

PDDocument pdDocument = document;

PDFRenderer renderer = new PDFRenderer(pdDocument);

/*根据总页数, 按照50页生成一张长图片的逻辑, 进行拆分*/

// 每50页转成1张图片

int pageLength = size; //有多少转多少

// 总计循环的次数

int totalCount = pdDocument.getNumberOfPages() / pageLength + 1;

for (int m = 0; m < totalCount; m++) {

for (int i = 0; i < pageLength; i++) {

int pageIndex = i + (m * pageLength);

if (pageIndex == pdDocument.getNumberOfPages()) {

System.out.println("m = " + m);

break;

}

// 96为图片的dpi，dpi越大，则图片越清晰，图片越大，转换耗费的时间也越多

BufferedImage image = renderer.renderImageWithDPI(pageIndex, 106, ImageType.RGB);

int imageHeight = image.getHeight();

int imageWidth = image.getWidth();

if (i == 0) {

//计算高度和偏移量

//使用第一张图片宽度;

width = imageWidth;

// 保存每页图片的像素值

// 加个判断：如果m次循环后所剩的图片总数小于pageLength，则图片高度按剩余的张数绘制，否则会出现长图片下面全是黑色的情况

if ((pdDocument.getNumberOfPages() - m * pageLength) < pageLength) {

imageResult = new BufferedImage(width, imageHeight * (pdDocument.getNumberOfPages() - m * pageLength), BufferedImage.TYPE_INT_RGB);

} else {

imageResult = new BufferedImage(width, imageHeight * pageLength, BufferedImage.TYPE_INT_RGB);

}

} else {

// 将高度不断累加

shiftHeight += imageHeight;

}

singleImgRGB = image.getRGB(0, 0, width, imageHeight, null, 0, width);

imageResult.setRGB(0, shiftHeight, width, imageHeight, singleImgRGB, 0, width);

}

// System.out.println("m = " + m);

File outFile = new File("C://Test//eClaimPDF//WrittenConfirmation.png");

System.out.println(outFile.getName());

// 写图片

ImageIO.write(imageResult, "png", outFile);

// 这个很重要，下面会有说明

shiftHeight = 0;

}

pdDocument.close();

ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

ImageIO.write(imageResult, "png", baos);//写入流中

byte[] jpg_Bytes = baos.toByteArray();//转换成字节

BASE64Encoder encoder = new BASE64Encoder();

jpg_base64 = encoder.encodeBuffer(jpg_Bytes).trim();//转换成base64串

jpg_base64 = jpg_base64.replaceAll("\n", "").replaceAll("\r", "");//删除 \r\n

// System.out.println("值为："+"data:image/jpg;base64,"+jpg_base64);

} catch (Exception e) {

e.printStackTrace();

}

return "data:image/jpg;base64,"+jpg_base64;

}

// private static String base64PdfToJpg(String base64Pdf) {

// String jpg_base64 = null;

// int pdfdpi = 400;

// BASE64Decoder decoder = new BASE64Decoder();

// byte[] pdf_bytes = null;

//try {

//pdf_bytes = decoder.decodeBuffer(base64Pdf);

//} catch (IOException e1) {

//e1.printStackTrace();

//}

// try (final PDDocument document = PDDocument.load(pdf_bytes)) {

// int size = document.getNumberOfPages();

// for (int i = 0; i < size; i++) {

// BufferedImage image = new PDFRenderer(document).renderImageWithDPI(i, pdfdpi, ImageType.RGB);

// BufferedImage image = new PDFRenderer(document).

// ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

// ImageIO.write(image, "jpg", baos);//写入流中

// byte[] jpg_Bytes = baos.toByteArray();//转换成字节

// BASE64Encoder encoder = new BASE64Encoder();

// jpg_base64 = encoder.encodeBuffer(jpg_Bytes).trim();//转换成base64串

// jpg_base64 = jpg_base64.replaceAll("\n", "").replaceAll("\r", "");//删除 \r\n

// System.out.println("值为："+"data:image/jpg;base64,"+jpg_base64);

// }

// } catch (Exception e) {

// e.printStackTrace();

// }

// return "data:image/jpg;base64,"+jpg_base64;

// }

private static void pdfTojpg(String pdfFilePath, String jpgFilePath) {

File pdfFile = new File(pdfFilePath);

int idx = jpgFilePath.lastIndexOf('.');

String jpgprefix = StringUtils.substring(jpgFilePath, 0, idx);

int pdfdpi = 400;

BASE64Decoder decoder = new BASE64Decoder();

byte[] bytes = null;

try {

bytes = decoder.decodeBuffer(pdfBase64);

} catch (IOException e1) {

e1.printStackTrace();

}

// try (final PDDocument document = PDDocument.load(pdfFile, "")) {

try (final PDDocument document = PDDocument.load(bytes)) {

int size = document.getNumberOfPages();

for (int i = 0; i < size; i++) {

BufferedImage image = new PDFRenderer(document).renderImageWithDPI(i, pdfdpi, ImageType.RGB);

* ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流

* ImageIO.write(image, "jpg", baos);//写入流中 byte[] imgBytes =

* baos.toByteArray();//转换成字节 BASE64Encoder encoder = new BASE64Encoder();

* String png_base64 = encoder.encodeBuffer(imgBytes).trim();//转换成base64串

* png_base64 = png_base64.replaceAll("\n", "").replaceAll("\r", "");//删除 \r\n

* System.out.println("值为："+"data:image/jpg;base64,"+png_base64);

File jpgFile = new File(jpgprefix + "_" + i + ".jpg");

ImageIO.write(image, "jpg", jpgFile);

}

} catch (Exception e) {

e.printStackTrace();

}

private static Double getDiffTime(Date lateTime, Date earlyTime) {

DecimalFormat df=new DecimalFormat("0.00");//设置保留位数

return Double.valueOf(df.format((double)(lateTime.getTime() - earlyTime.getTime()) / 1000));

}

public static String pdfBase64 = "***" //from web 网页链接, upload a PDF to get the base64 string (Base64 - Online Base64 decoder and encoder)

}

热心网友时间：2022-04-24 09:37

如果桌面没有迅雷快捷方式，可以到开始菜单里的【所有程序】里查找

热心网友时间：2022-04-24 11:12

base64不就是一串字符吗、这还有格式？