added a shift parameter for the lsb module. closes #25

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Cédric Bonhomme 2019-06-01 11:53:07 +02:00
parent 37aeb39167
commit c3f6f392f3
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GPG key ID: A1CB94DE57B7A70D
2 changed files with 25 additions and 10 deletions

View file

@ -20,9 +20,9 @@
# along with this program. If not, see <http://www.gnu.org/licenses/>
__author__ = "Cedric Bonhomme"
__version__ = "$Revision: 0.7 $"
__version__ = "$Revision: 0.8 $"
__date__ = "$Date: 2016/08/04 $"
__revision__ = "$Date: 2017/05/16 $"
__revision__ = "$Date: 2019/06/01 $"
__license__ = "GPLv3"
try:
@ -58,6 +58,9 @@ group_secret.add_argument("-f", dest="secret_file",
parser_hide.add_argument("-o", "--output", dest="output_image_file",
required=True, help="Output image containing the secret.")
# Shift the message to hide
parser_hide.add_argument("-s", "--shift", dest="shift", default=0,
help="Shift for the message to hide")
# Subparser: Reveal
parser_reveal = subparsers.add_parser('reveal', help='reveal help')
@ -69,7 +72,9 @@ parser_reveal.add_argument("-e", "--encoding", dest="encoding",
" UTF-8 (default) or UTF-32LE.")
parser_reveal.add_argument("-o", dest="secret_binary",
help="Output for the binary secret (Text or any binary file).")
# Shift the message to reveal
parser_reveal.add_argument("-s", "--shift", dest="shift", default=0,
help="Shift for the reveal")
arguments = parser.parse_args()
@ -81,7 +86,7 @@ if arguments.command == 'hide':
secret = tools.binary2base64(arguments.secret_file)
img_encoded = lsb.hide(arguments.input_image_file, secret,
arguments.encoding)
arguments.encoding, int(arguments.shift))
try:
img_encoded.save(arguments.output_image_file)
except Exception as e:
@ -89,7 +94,8 @@ if arguments.command == 'hide':
print(e)
elif arguments.command == 'reveal':
secret = lsb.reveal(arguments.input_image_file, arguments.encoding)
secret = lsb.reveal(arguments.input_image_file, arguments.encoding,
int(arguments.shift))
if arguments.secret_binary != None:
data = tools.base642binary(secret)
with open(arguments.secret_binary, "wb") as f:

View file

@ -1,7 +1,7 @@
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Stéganô - Stéganô is a basic Python Steganography module.
# Stéganô - Stegano is a basic Python Steganography module.
# Copyright (C) 2010-2019 Cédric Bonhomme - https://www.cedricbonhomme.org
#
# For more information : https://github.com/cedricbonhomme/Stegano
@ -20,9 +20,9 @@
# along with this program. If not, see <http://www.gnu.org/licenses/>
__author__ = "Cedric Bonhomme"
__version__ = "$Revision: 0.3 $"
__version__ = "$Revision: 0.4 $"
__date__ = "$Date: 2016/08/04 $"
__revision__ = "$Date: 2017/05/04 $"
__revision__ = "$Date: 2019/06/01 $"
__license__ = "GPLv3"
from typing import IO, Union
@ -34,6 +34,7 @@ def hide(
input_image: Union[str, IO[bytes]],
message: str,
encoding: str = "UTF-8",
shift: int = 0,
auto_convert_rgb: bool = False,
):
"""Hide a message (string) in an image with the
@ -72,6 +73,9 @@ def hide(
)
for row in range(height):
for col in range(width):
if shift != 0:
shift -= 1
continue
if index + 3 <= len_message_bits:
# Get the colour component.
@ -97,7 +101,10 @@ def hide(
return encoded
def reveal(input_image: Union[str, IO[bytes]], encoding="UTF-8"):
def reveal(input_image: Union[str, IO[bytes]],
encoding: str = "UTF-8",
shift: int = 0
):
"""Find a message in an image (with the LSB technique).
"""
img = tools.open_image(input_image)
@ -107,7 +114,9 @@ def reveal(input_image: Union[str, IO[bytes]], encoding="UTF-8"):
limit = None
for row in range(height):
for col in range(width):
if shift != 0:
shift -= 1
continue
# pixel = [r, g, b] or [r,g,b,a]
pixel = img.getpixel((col, row))
if img.mode == "RGBA":