How to send image as bytes, and send json data together in the same HTTP request?

Question

I'm trying to send image as bytes because bandwidth is being killed by base64 strings. I've seen examples about transferring it as stream https://stackoverflow.com/a/17573179/8359785 but the problem is that I'm not sure how to transfer json data with it at the same http request

Add a field in the `JSON` to accommodate the **image** `Bytes`. — Saif Ahmad, Jan 09 '18 at 12:16
How to do that when json can't handle binary data ,_, or am i missing something here? — Waseem, Jan 09 '18 at 12:20
Use multipart? One part for the Json and one part for the image. I would try and provide some useful information/example code but I don't know what libraries you're using, etc. — BeUndead, Jan 09 '18 at 12:46

score 1 · Answer 1 · answered Jan 09 '18 at 12:34

1

You could add a field in the JSON to accommodate the Byte[] of your Image.

JSON could be like this:

{
    ...,

    "Image": [83, 97, 105, 102, 32, 115, 97, 121, 115, 32, 104, 101, 108, 108, 111],//Byte array of your image

    ...
}

answered Jan 09 '18 at 12:34

Saif Ahmad

1,118
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That actually worked, didn't expect it to. Thanks a lot! I'll also try other solutions though to see which saves as much bandwidth as possible. – Waseem Jan 09 '18 at 13:05
After testing the difference, this appears to use double the amount of bandwidth than when transferring base64.. But still, good to know that bytes can be included in json – Waseem Jan 09 '18 at 13:37
I gave answer for **How to accommodate Byte in JSON** if you want to save bandwidth, there is a better of doing it. – Saif Ahmad Jan 09 '18 at 18:18

BluEOS · Accepted Answer · 2018-01-09T13:11:45.890

1

If you need to reduce the bandwidth usage to its maximum, just send data like this :

DataOutputStream dOut = new DataOutputStream(socket.getOutputStream());
dOut.writeInt(imageBytes.length); 
dOut.write(imageBytes);
dOut.writeInt(jsonBytes.length); 
dOut.write(jsonBytes);

Receive code:

DataInputStream dIn = new DataInputStream(socket.getInputStream());
int imageBytesLength = dIn.readInt();  
byte[] imageBytes= new byte[imageBytesLength];
dIn.readFully(imageBytes, 0, imageBytesLength); 
int jsonBytesLength = dIn.readInt();  
byte[] jsonBytes= new byte[jsonBytesLength ];
dIn.readFully(jsonBytesLength , 0, jsonBytesLength );

edited Jan 09 '18 at 13:11

answered Jan 09 '18 at 13:00

BluEOS

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And how would the two things be received in the server? O.o – Waseem Jan 09 '18 at 13:04
@BluEOS the OP asked for HTTP post but you gave answer for Socket? – Saif Ahmad Jan 09 '18 at 18:11

How to send image as bytes, and send json data together in the same HTTP request?

2 Answers2