python - Broken image when decoding base64 string -

i'm trying send user image ios app python script through firebase creating base64 string image , posting string firebase , decoding in python. however, corrupted image produced. how fix this? here swift code:

    func imagepickercontroller(picker: uiimagepickercontroller, didfinishpickingmediawithinfo info: [string : anyobject]) {     var bytearray = nsdata()     if let file = info[uiimagepickercontrolleroriginalimage] as? uiimage {         bytearray = uiimagejpegrepresentation(file, 1.0)!     }     let b64 = bytearray.base64encodedstringwithoptions(nsdatabase64encodingoptions(rawvalue: 0))     firdatabase.database().reference().child("datauploaded").setvalue(b64)     uploaded = true     dismissviewcontrolleranimated(true, completion: nil)     } 

and python code:

from firebase import firebase import os pil import image import numpy np import io  fb = firebase.firebaseapplication("https://xxxxxx.firebaseio.com/", none) = fb.get('/datauploaded', none)  filename = 'image.png' open(filename, 'wb') f: f.write(a)