使用java将图像转换为base64

Question

I need to convert a image object to a base64 object so I can load it into the tag on my client side.我需要将图像对象转换为 base64 对象，以便可以将其加载到客户端的标签中。

However I can't seem to figure out how to pull this off.但是我似乎无法弄清楚如何解决这个问题。 Is there anyone who has a piece of code for this that I could use easily?有没有人有一段我可以轻松使用的代码？

This is what I use to turn the external image link into a image object这就是我用来将外部图像链接转换为图像对象的方法

Image image = null;
URL url = new URL(request.getParameter("hdn_path"));
image = ImageIO.read(url);

not sure if I'm going about this the correct way.不知道我是否以正确的方式解决这个问题。

Answer 1

Using Apache IOUtils and Base64 :使用 Apache IOUtils和Base64 ：

byte[] imageBytes = IOUtils.toByteArray(new URL("...")));
String base64 = Base64.getEncoder().encodeToString(imageBytes);

Answer 2

write using ImageIO.write().使用 ImageIO.write() 写入。
ByteArrayOutputStream wraps the byte array so it can be used as an output stream. ByteArrayOutputStream 包装字节数组，因此它可以用作输出流。
convert the byte array to aa base64 string using DatatypeConverter, in core Java since 6, no extra libraries required使用 DatatypeConverter 将字节数组转换为 base64 字符串，在核心 Java 中，从 6 开始，不需要额外的库

Example例子

ByteArrayOutputStream output = new ByteArrayOutputStream();
ImageIO.write(image, "png", output);
DatatypeConverter.printBase64Binary(output.toByteArray());

Answer 3

Accepted answer reads the file from URL, if any one looking for image to Base64 encoding by reading the image from file system, below snippet can be used.接受的答案从 URL 读取文件，如果有人通过从文件系统读取图像来寻找 Base64 编码的图像，则可以使用以下代码段。

import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Base64;
import org.apache.commons.io.IOUtils;

public String img2Text(){
    String base64="";
    try{
        InputStream iSteamReader = new FileInputStream("featured-700x467.png");
        byte[] imageBytes = IOUtils.toByteArray(iSteamReader);
        base64 = Base64.getEncoder().encodeToString(imageBytes);
        System.out.println(base64);
    }catch(Exception e){
        e.printStackTrace();
    }
    return "data:image/png;base64,"+base64;
}

Returned base64 text can be used in HTML pages like below example返回的 base64 文本可用于 HTML 页面，如下例所示

 <!DOCTYPE html> <html> <body> <img src="data:image/png;base64,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 " alt="Smiley face" width="42" height="42"> </body> </html>

Answer 4

String imageURL = "https://avatars.githubusercontent.com/u/12166061?v=4" //I was saved image from remote address 
  
Base64.getEncoder().encodeToString(IOUtils.toByteArray(new URL(imageURL).openStream()))

使用java将图像转换为base64

问题描述

4 个解决方案

解决方案1
15 已采纳 2015-02-01 22:19:54

解决方案2
5 2015-02-01 22:15:53

解决方案3
4 2018-07-16 21:38:40

解决方案4
-1 2022-06-16 12:20:30

使用java将图像转换为base64

问题描述

4 个解决方案

解决方案1 15 已采纳 2015-02-01 22:19:54

解决方案2 5 2015-02-01 22:15:53

解决方案3 4 2018-07-16 21:38:40

解决方案4 -1 2022-06-16 12:20:30

解决方案1
15 已采纳 2015-02-01 22:19:54

解决方案2
5 2015-02-01 22:15:53

解决方案3
4 2018-07-16 21:38:40

解决方案4
-1 2022-06-16 12:20:30