How to convert an Image to base64 string in java?

Question

It may be a duplicate but i am facing some problem to convert the image into Base64 for sending it for Http Post. I have tried this code but it gave me wrong encoded string.

 public static void main(String[] args) {

           File f =  new File("C:/Users/SETU BASAK/Desktop/a.jpg");
             String encodstring = encodeFileToBase64Binary(f);
             System.out.println(encodstring);
       }

       private static String encodeFileToBase64Binary(File file){
            String encodedfile = null;
            try {
                FileInputStream fileInputStreamReader = new FileInputStream(file);
                byte[] bytes = new byte[(int)file.length()];
                fileInputStreamReader.read(bytes);
                encodedfile = Base64.encodeBase64(bytes).toString();
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return encodedfile;
        }

Output: [B@677327b6

But i converted this same image into Base64 in many online encoders and they all gave the correct big Base64 string.

Edit: How is it a duplicate?? The link which is duplicate of mine doesn't give me solution of converting the string what i wanted.

What am i missing here??

How are you determining that this be the incorrect base 64 string? — Tim Biegeleisen, Apr 08 '16 at 05:23
Can you provide code for the POST method ? I'm in the same problem ( post an image ... ) Thanks!! — Yekatandilburg, Feb 24 '17 at 16:52

score 38 · Accepted Answer · answered Apr 08 '16 at 05:34

38

The problem is that you are returning the toString() of the call to Base64.encodeBase64(bytes) which returns a byte array. So what you get in the end is the default string representation of a byte array, which corresponds to the output you get.

Instead, you should do:

encodedfile = new String(Base64.encodeBase64(bytes), "UTF-8");

answered Apr 08 '16 at 05:34

Lolo

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That solved my issue – Setu Kumar Basak Apr 08 '16 at 05:35
5

String strBase64=Base64.encodeToString(byteArray, 0) – Patel Vicky Apr 08 '16 at 05:46

score 18 · Answer 2 · answered Apr 08 '16 at 05:32

18

I think you might want:

String encodedFile = Base64.getEncoder().encodeToString(bytes);

answered Apr 08 '16 at 05:32

Joels Elf

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import org.apache.commons.codec.binary.Base64; I am importing this.. here Base64 doesn't have getEncoder() like things – Setu Kumar Basak Apr 08 '16 at 05:34
1

@setubasak it is about `java.util.Base64` added in Java 8. – Pshemo Apr 08 '16 at 05:38

score 7 · Answer 3 · edited Nov 23 '16 at 12:06

7

this did it for me. you can vary the options for the output format to Base64.Default whatsoever.

// encode base64 from image
ByteArrayOutputStream baos = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
byte[] b = baos.toByteArray();
encodedString = Base64.encodeToString(b, Base64.URL_SAFE | Base64.NO_WRAP);

edited Nov 23 '16 at 12:06

Flummox - don't be evil SE

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answered Apr 08 '16 at 05:23

MojioMS

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where to feed my image file?? – Setu Kumar Basak Apr 08 '16 at 05:26
here, it is loaded into imageBitmap. method .compress converts and encodes it into baos – MojioMS Apr 08 '16 at 05:28
Base64.URL_SAFE these are not working for me?? what is to import?? – Setu Kumar Basak Apr 08 '16 at 05:30
sorry, i just noticed this is not about android. I will look up for a working solution – MojioMS Apr 08 '16 at 05:30

How to convert an Image to base64 string in java?

3 Answers3

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