ecb encrypted result

aes_ecb_test.py

# -*- coding: utf-8 -*-

from Crypto.Cipher import AES

f = open('before.bmp','rb')
bid_header = f.read(54)
raw_data = f.read()
f.close()

pad = lambda s: s + (16 - len(s) % 16) * chr(16 - len(s) % 16)
cryptor = AES.new('use for ecb test', AES.MODE_ECB)
cipher_data = cryptor.encrypt(pad(raw_data))

f = open('after.bmp','wb')
f.write(bid_header)
f.write(cipher_data)
f.close()

emmm, multimedia course lecturer says .bmp use run length encoding...