def __init__(self, image_path):
super(Steganography, self).__init__()
self._image_path = image_path
if self._image_path[-4:] != ".bmp":
raise NotBMPError("File is not type BMP")
self._pixel_data = PixelData(self._image_path)
class Steganography(object):
"""hide text information from the console or input file in BMP "
"format image. Or removal of text from the image in BMP format "
"console or output text file"""
def __init__(self, image_path):
super(Steganography, self).__init__()
self._image_path = image_path
if self._image_path[-4:] != ".bmp":
raise NotBMPError("File is not type BMP")
self._pixel_data = PixelData(self._image_path)
def _bin_message(self, information, len_byte_message):
bin_information_len = bin(len_byte_message)[2:].zfill(32)
bin_information = []
bin_information.append(bin_information_len)
for byte in information:
bin_byte = bin(byte)[2:].zfill(8)
bin_information.append(bin_byte)
else:
bin_information = ''.join(bin_information)
list_bit = tuple(map(int, bin_information))
return list_bit
def _separation(self, bin_message, pixel_data):
"""divides the binary data is too big"""
separation_bin_message = []
size_image = pixel_data.get_width() *\
pixel_data.get_height() * pixel_data.get_pixel_size()
valueblock = len(bin_message) // size_image
ost = len(bin_message) % size_image
for i in range(valueblock):
block = bin_message[size_image * i:size_image * (i + 1)]
separation_bin_message.append(block)
else:
try:
block = bin_message[
size_image * (i + 1):size_image * (i + 1) + ost]
except UnboundLocalError:
block = bin_message[:ost]
if block:
separation_bin_message.append(block)
return separation_bin_message
@staticmethod
def _set_bit(byte, index, bit):
"""sets bit number"""
mask = 1 << index
byte &= ~mask
if bit:
byte |= mask
return byte
def hide_information(
self, information, out_file=None):
"""hide information in the image data"""
if type(information) is str:
information = information.encode()
len_byte_message = len(information)
capacity_image = self._pixel_data.get_height() *\
self._pixel_data.get_width() * self._pixel_data.get_pixel_size()
if capacity_image < len_byte_message + 4:
raise LengthError('Information does not fit into the picture. \
Length of the information: {0}. Сapacity image: \
{1}'.format(len_byte_message, capacity_image))
bin_message = self._bin_message(information, len_byte_message)
separation_bin_message =\
self._separation(bin_message, self._pixel_data)
byte_array = self._pixel_data.get_pixel_data()
number_bit = 0
byte_array = list(byte_array)
for piece_bin_message in separation_bin_message:
setBit = (i for i in piece_bin_message)
for i in range(len(byte_array)):
try:
nextBit = next(setBit)
byte_array[i] = Steganography._set_bit(
byte_array[i], number_bit, nextBit)
except StopIteration:
break
number_bit += 1
self._pixel_data.write_new_image(bytes(byte_array), out_file)
@staticmethod
def _get_bit(byte, index):
"""returns the number of bits"""
bit = str(int(byte & 1 << index != 0))
return bit
@staticmethod
def _get_allByte(bin_information):
"""returns all bytes of binary information"""
counter = 0
byte = ""
all_bytes = []
for bit in bin_information:
byte += bit
counter += 1
if counter == 8:
all_bytes.append(int(byte, 2))
byte = ""
counter = 0
return bytes(all_bytes)
def unhide_information(self, out_file=None):
"""discloses information from image"""
byteArray = self._pixel_data.get_pixel_data()
len_bit_information = ""
len_information = None
number_bit = 0
get_byte = (i for i in byteArray)
for i in range(32):
try:
nextByte = next(get_byte)
len_bit_information +=\
Steganography._get_bit(nextByte, number_bit)
except StopIteration:
number_bit += 1
get_byte = (i for i in byteArray)
nextByte = next(get_byte)
len_bit_information +=\
Steganography._get_bit(nextByte, number_bit)
else:
len_information = int(len_bit_information, 2) * 8
information_need_bits = ""
for i in range(len_information):
try:
nextByte = next(get_byte)
information_need_bits +=\
Steganography._get_bit(nextByte, number_bit)
except StopIteration:
number_bit += 1
get_byte = (i for i in byteArray)
nextByte = next(get_byte)
information_need_bits +=\
Steganography._get_bit(nextByte, number_bit)
comlete_information = Steganography._get_allByte(information_need_bits)
if out_file:
with open(out_file, "wb") as out_file:
out_file.write(comlete_information)
else:
print(comlete_information.decode('utf-8'))
@staticmethod
def test():
"""testing method"""
stegH = Steganography(os.path.join(path[0], "test", "in_image.bmp"))
lever = False
print("Test hide/unhide english txt:")
with open(os.path.join(
path[0], "test", "input1.txt"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output1.txt"))
if getsize(os.path.join(path[0], "test", "input1.txt")) == getsize(
os.path.join(path[0], "test", "output1.txt")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Test hide/unhide russian txt:")
with open(os.path.join(
path[0], "test", "input5.txt"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output5.txt"))
if getsize(os.path.join(path[0], "test", "input5.txt")) == getsize(
os.path.join(path[0], "test", "output5.txt")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Test hide/unhide en/ru txt:")
with open(os.path.join(
path[0], "test", "input6.txt"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output6.txt"))
if getsize(os.path.join(path[0], "test", "input6.txt")) == getsize(
os.path.join(path[0], "test", "output6.txt")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Test hide/unhide png:")
with open(os.path.join(
path[0], "test", "input2.png"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output2.png"))
if getsize(os.path.join(path[0], "test", "input2.png")) == getsize(
os.path.join(path[0], "test", "output2.png")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Test hide/unhide rar:")
with open(os.path.join(
path[0], "test", "input3.rar"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output3.rar"))
if getsize(os.path.join(path[0], "test", "input3.rar")) == getsize(
os.path.join(path[0], "test", "output3.rar")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Test hide/unhide exe:")
with open(os.path.join(
path[0], "test", "input4.exe"), 'rb') as inputFile:
stegH.hide_information(
inputFile.read(), os.path.join(path[0], "test", "steg.bmp"))
stegU = Steganography(os.path.join(path[0], "test", "steg.bmp"))
stegU.unhide_information(
os.path.join(path[0], "test", "output4.exe"))
if getsize(os.path.join(
path[0], "test", "input4.exe")) == getsize(
os.path.join(path[0], "test", "output4.exe")):
print("Verification was successful")
else:
print("Validation fails")
lever = True
print("Complete test")
return lever