def test_hideBit5(self):
b = byte_tools.hide_data(42, 2, 4)
self.assertEqual(34, b)
def hide(self, bin_data, order_num=0, bad_bits_num=1):
bin_data = pack(">L", len(bin_data)) + bin_data
if len(bin_data) > self.container_space(bad_bits_num):
raise ContainerException("Too much data to hide. {}: but max={}".format(
len(bin_data), self.container_space())
)
order_inspector = ORDER_INSPECTORS[order_num](self.container_space())
sample_id = 0
pos = 0
hidden_data_byte = 0
bits_data = byte_tools.to_bits(bin_data)
for i in range(len(bits_data)):
hidden_data_byte = hidden_data_byte * 2 + bits_data[i]
pos += 1
if (pos == bad_bits_num) or (i + 1 == len(bits_data)):
if i + 1 == len(bits_data) and not (pos == bad_bits_num):
while pos != bad_bits_num:
hidden_data_byte *= 2
pos += 1
self[sample_id] = byte_tools.hide_data(self[sample_id], hidden_data_byte, bad_bits_num)
pos = 0
hidden_data_byte = 0
sample_id = order_inspector.next()
def test_hideBit2(self):
b = byte_tools.hide_data(0, 0)
self.assertEqual(0, b)
def test_reveal(self):
byte = 234213
hidden_data = 9
number_of_bad_bits = 15
bad_byte = byte_tools.hide_data(byte, hidden_data, number_of_bad_bits)
released_data = byte_tools.reveal_data(bad_byte, number_of_bad_bits)
self.assertEqual(hidden_data, released_data)
def test_hideBit4(self):
b = byte_tools.hide_data(567, 5)
self.assertEqual(565, b)
def test_hideBit3(self):
b = byte_tools.hide_data(250, 1)
self.assertEqual(251, b)
def test_hideBit1(self):
b = byte_tools.hide_data(0, 1)
self.assertEqual(1, b)
