python Image PIL to binary Hex

问题

from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
import urllib.request
import io
import binascii

data = urllib.request.urlopen('http://pastebin.ca/raw/2311595').read()
r_data = binascii.unhexlify(data)
stream = io.BytesIO(r_data)
img = Image.open(stream)
draw = ImageDraw.Draw(img)
font = ImageFont.truetype("arial.ttf",14)
draw.text((0, 220),"This is a test11",(0,255,0),font=font)
draw = ImageDraw.Draw(img)

with open(img,'rb') as in_file: #error on here invalid file:
     hex_data = in_file.read()
# Unhexlify the data.
bin_data = binascii.unhexlify(bytes(hex_data))
print(bin_data)

Question

converting hex to image and draw a text on the image, after that convert image to binary hex,but having the problem at here with open(img,'rb') as in_file:, how to convert img to hex?

回答1:

The img object needs to be saved again; write it to another BytesIO object:

output = io.BytesIO()
img.save(output, format='JPEG')

then get the written data with the .getvalue() method:

hex_data = output.getvalue()

The PIL-for-python-3 landscape is rather muddled at the moment. The Pillow fork looks to be the best, maintained version out there at the moment. It includes fixes that make saving to a BytesIO object work. If you run into a io.UnsupportedOperation: fileno exception using the above code, you have a version that was not yet fixed, in which case you'll have to resort to using a temporary file instead.

来源：https://stackoverflow.com/questions/14921055/python-image-pil-to-binary-hex