StegoEncrypt.py

#!/usr/bin/python
__author__ = 'kilroy'
#  (c) 2014, WasHere Consulting, Inc.
#  Written for Infinite Skills

# need pycrypto package
from Crypto.Cipher import AES
# need PIL and stepic packages
import Image, stepic
import binascii

# key has to be 16, 24 or 32 bytes long
cryptObj = AES.new("This is my key42", AES.MODE_CBC, "16 character vec")
#  notice the spaces -- that's to pad it out to a multiple of 16 bytes
plaintext = "This is some text we need to encrypt because it's very secret   "
ciphertext = cryptObj.encrypt(plaintext)

#  we need to convert to ASCII to store it nicely
binval = binascii.b2a_base64(ciphertext)
i = Image.open("bullpuppies.jpg")

print("ASCII: ", binval)
stego = stepic.encode(i, binval)
stego.save("stegencrypt.bmp", "BMP")

newim = Image.open("stegencrypt.bmp")
data = stepic.decode(newim).rstrip('\n')

print("What we have out: ", data)
#  convert from ASCII back to binary
encrypted = binascii.a2b_base64(data)

newcryptObj = AES.new("This is my key42", AES.MODE_CBC, "16 character vec")
result = newcryptObj.decrypt(encrypted)

print(result)