LatexUtils.java

package com.subsidy.util;

import org.scilab.forge.jlatexmath.TeXConstants;
import org.scilab.forge.jlatexmath.TeXFormula;
import org.scilab.forge.jlatexmath.TeXIcon;

import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;

/**
 * @author: tuyp
 * @create: 2020-08-08 21:19
 */
public class LatexUtils {

    /**
     * @Description: 将base64编码字符串转换为图片
     * @Author:
     * @CreateTime:
     * @param imgStr
     *            base64编码字符串
     * @param path
     *            图片路径-具体到文件
     * @return
     */
    public static boolean generateImage(String imgStr, String path) {
        if (imgStr == null) {
            return false;
        }
//        BASE64Decoder decoder = new BASE64Decoder();
        try {
//            byte[] b = decoder.decodeBuffer(imgStr);
//            for (int i = 0; i < b.length; i++) {
//                if (b[i] < 0) {
//                    b[i] += 256;
//                }
//            }
//            OutputStream out = new FileOutputStream(path);
//            out.write(b);
//            out.flush();
//            out.close();
            return true;
        } catch (Exception e) {
            // TODO: handle exception
            return false;
        }
    }

    /**
     * @Description: 根据图片地址转换为base64编码字符串
     * @Author:
     * @CreateTime:
     * @return
     */
//    public static String getImageStr(String imgFile) {
//        InputStream inputStream = null;
//        byte[] data = null;
//        try {
//            inputStream = new FileInputStream(imgFile);
//            data = new byte[inputStream.available()];
//            inputStream.read(data);
//            inputStream.close();
//        } catch (IOException e) {
//            e.printStackTrace();
//        }
//        // 加密
//        BASE64Encoder encoder = new BASE64Encoder();
//        return encoder.encode(data);
//    }

    // latex 转 imgbase64
    public static String latex2Png(String latex) {
        try {
            TeXFormula formula = new TeXFormula(latex);
            // render the formla to an icon of the same size as the formula.
            TeXIcon icon = formula.createTeXIcon(TeXConstants.STYLE_DISPLAY, 20);
            // insert a border
            icon.setInsets(new Insets(1, 1, 1, 1));
            // now create an actual image of the rendered equation
            BufferedImage image = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_BYTE_GRAY);
            Graphics2D g2 = image.createGraphics();
            g2.setColor(Color.white);
            g2.fillRect(0, 0, icon.getIconWidth(), icon.getIconHeight());
            JLabel jl = new JLabel();
            jl.setForeground(new Color(0, 0, 0));
            icon.paintIcon(jl, g2, 0, 0);
            // at this point the image is created, you could also save it with ImageIO
            // saveImage(image, "png", "F:\\b.png");
//             ImageIO.write(image, "png", new File("F:\\c.png"));
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            try {
                ImageIO.write(image, "png", outputStream);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                return null;
            }
            byte[] buffer = outputStream.toByteArray();
//            BASE64Encoder encoder = new BASE64Encoder();
            return ("data:image/png;base64,");
        } catch (Exception e) {
            // e.printStackTrace();
            // ExceptionUtil.log(log, e);
            System.err.println("公式解析有误：\n" + latex);
            // e.printStackTrace();
            return null;
        }
    }

    public static void main(String[] args) {
        String str = latex2Png("\\(\\sqrt[3]{2+x}\\)");
        System.out.println(str);




//        String omml =Latex_Word.latexToWord(str);
//        System.out.println(omml);
    }

}