How can I pass images in a server's response using JSON? Base64?

Question

In my android app, I show some users in a ListView. I want to display (user's pic, first_name, last_name). Right now, it works only with first_name and last_name. I want to add the picture. The data JSON I receive from my server (python) is like this:

[{"profil":"first_name": "Jim", "last_name": "Carrey"}}, "_id": {"$oid": "4d595cda1d41c81536000000"}}, {"profil":{"first_name": "Mathieu", "last_name": "Polnari"}}, "_id": {"$oid": "4d5916581d41c80e88000000"}}, {"profil": {"first_name": "Vincent", "last_name": "Fatou"}}, "_id": {"$oid": "4d58fc7e1d41c8090e000000"}}...] 

It should be better if I add one parameter in that JSON for the picture.

Do you think it is a good idea to return the picture as a string in the JSON et use Base64 to decode it?

Answer 1

Technically it's perfectly ok to encode binary data as base64 string and include it in JSON.

But, as @servermanfail noted, you might be better off with embedding links to images into JSON and downloading them in the second step.

The added benefit would be size/speed of transfer, as base64 stream is 4/3 the size of the original binary stream (33% overhead).

Also, in this case, you could cache images.

Answer 2

I would suggest adding a JSON parameter which contains a URL to the resource.

For added security, you could create encrypted URLs by adding a md5 with salt checksum to the resource, like http://server.com/images/1234567890123456789012345678901234567890/image.jpg - this is the method facebook.com uses.