requirements.txt

Pillow==3.3.1

test_external.py

import urllib2
from io import BytesIO
from PIL import Image

url = 'http://cdn1.www.st-hatena.com/users/da/daiiz/profile.gif?1451834248'

filePointer = urllib2.urlopen(url)
data = filePointer.read()
filePointer.close()

image = Image.open(BytesIO(data))
image.show()

test_jpegdata.py

from PIL import Image
from io import BytesIO
import base64

data = 'R0lGODlhDwAPAKECAAAAzMzM/////wAAACwAAAAADwAPAAACIISPeQHsrZ5ModrLlN48CXF8m2iQ3YmmKqVlRtW4MLwWACH+H09wdGltaXplZCBieSBVbGVhZCBTbWFydFNhdmVyIQAAOw=='
bytesdata = BytesIO(base64.b64decode(data))

im = Image.open(bytesdata)
im.show()