Handling Base64 files

更新时间:
复制 MD 格式

Some Alibaba Cloud Visual Intelligence API services accept Base64-encoded files. The platform decodes these files before processing them.

Note

If you have questions about API access, usage, or other features of the Visual Intelligence API, you can join our DingTalk group (23109592) to contact us.

Test sample

To verify that your Base64 content is encoded correctly, you can use the following test sample: base64Test.

You can download the sample file and encode it to Base64. The correct result is:

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

Using a tool

You can search for and use a Base64 tool, or install a command line interface to encode the file.

The following example uses a macOS environment:

  1. You can install the base64 tool using Homebrew. For more information, see Homebrew.

    brew install base64
  2. You can encode the file using the base64 tool.

    base64Test.png is the name of your file.

    base64 base64Test.png

Code Processing

You can also encode a file to Base64 using code. The following example uses Java.

Java code example:

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Base64;

public class Main {

    public static String encryptToBase64(String filePath) {
        if (filePath == null) {
            return null;
        }
        try {
            byte[] b = Files.readAllBytes(Paths.get(filePath));
            return Base64.getEncoder().encodeToString(b);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null;
    }

    public static void main(String[] args) {
        System.out.println(encryptToBase64("/tmp/base64Test.png"));
    }

}
Note

This example requires Java 8 or later.

FAQ

What if my string has a data:image/png;base64, prefix?

If you obtain a Base64 string in a format such as data:image/png;base64,xxxx, do not include the data:image/png;base64, prefix when you pass the string to the API. Send only the part that starts with xxxx.