Steganalysis/total_test.py

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2021-12-30 11:48:37 +00:00
# -*- coding: utf-8 -*-
"""
Created on Wed Jun 12 09:36:29 2019
@author: Administrator
"""
import math
import numpy as np
import DCT
class Jsteg:
def __init__(self):
self.sequence_after_dct=None
def set_sequence_after_dct(self,sequence_after_dct):
self.sequence_after_dct=sequence_after_dct
self.available_info_len=len([i for i in self.sequence_after_dct if i not in (-1,1,0)]) # 不是绝对可靠的
print ("Load>> 可嵌入",self.available_info_len,'bits')
def get_sequence_after_dct(self):
return self.sequence_after_dct
def write(self,info):
"""先嵌入信息的长度，然后嵌入信息"""
info=self._set_info_len(info)
info_len=len(info)
info_index=0
im_index=0
while True:
if info_index>=info_len:
break
data=info[info_index]
if self._write(im_index,data):
info_index+=1
im_index+=1
#print(self.sequence_after_dct)
b={0:0,1:0,2:0,3:0,4:0,5:0,6:0,7:0,8:0,-1:0,-2:0,-3:0,-4:0,-5:0,-6:0,-7:0,-8:0}
for i in self.sequence_after_dct:
if i in b:
b[i]+=1
print("经过信息隐藏后JPEG的DCT系数变化")
print(b)
def read(self):
"""先读出信息的长度，然后读出信息"""
_len,sequence_index=self._get_info_len()
info=[]
info_index=0
while True:
if info_index>=_len:
break
data=self._read(sequence_index)
if data!=None:
info.append(data)
info_index+=1
sequence_index+=1
return info
#===============================================================#
def _set_info_len(self,info):
l=int(math.log(self.available_info_len,2))+1
info_len=[0]*l
_len=len(info)
info_len[-len(bin(_len))+2:]=[int(i) for i in bin(_len)[2:]]
#print(info_len+info)
return info_len+info
def _get_info_len(self):
l=int(math.log(self.available_info_len,2))+1
len_list=[]
_l_index=0
_seq_index=0
while True:
if _l_index>=l:
break
_d=self._read(_seq_index)
if _d!=None:
len_list.append(str(_d))
_l_index+=1
_seq_index+=1
_len=''.join(len_list)
_len=int(_len,2)
return _len,_seq_index
# 注意经过DCT会有负值，此处最低有效位的嵌入方式与空域LSB略有不同
def _write(self,index,data):
origin=self.sequence_after_dct[index]
if origin in (-1,1,0):
return False
lower_bit=origin%2
if lower_bit==data:
pass
elif origin>0:
if (lower_bit,data) == (0,1):
self.sequence_after_dct[index]=origin+1
elif (lower_bit,data) == (1,0):
self.sequence_after_dct[index]=origin-1
elif origin<0:
if (lower_bit,data) == (0,1):
self.sequence_after_dct[index]=origin-1
elif (lower_bit,data) == (1,0):
self.sequence_after_dct[index]=origin+1
return True
def _read(self,index):
if self.sequence_after_dct[index] not in (-1,1,0):
return self.sequence_after_dct[index]%2
else:
return None
class F3(Jsteg):
def __init__(self):
Jsteg.__init__(self)
def set_sequence_after_dct(self,sequence_after_dct):
self.sequence_after_dct=sequence_after_dct
sum_len=len(self.sequence_after_dct)
zero_len=len([i for i in self.sequence_after_dct if i==0])
one_len=len([i for i in self.sequence_after_dct if i in (-1,1)])
self.available_info_len=sum_len-zero_len-one_len # 不是特别可靠
print ("Load>> 大约可嵌入",sum_len-zero_len-int(one_len/2),'bits')
print ("Load>> 最少可嵌入",self.available_info_len,'bits\n')
def _write(self,index,data):
origin=self.sequence_after_dct[index]
if origin == 0:
return False
elif origin in (-1,1) and data==0:
self.sequence_after_dct[index]=0
return False
lower_bit=origin%2
if lower_bit==data:
pass
elif origin>0:
self.sequence_after_dct[index]=origin-1
elif origin<0:
self.sequence_after_dct[index]=origin+1
return True
def _read(self,index):
if self.sequence_after_dct[index] != 0:
return self.sequence_after_dct[index]%2
else:
return None
class F4(Jsteg):
def __init__(self):
Jsteg.__init__(self)
def set_sequence_after_dct(self,sequence_after_dct):
self.sequence_after_dct=sequence_after_dct
sum_len=len(self.sequence_after_dct)
zero_len=len([i for i in self.sequence_after_dct if i==0])
one_len=len([i for i in self.sequence_after_dct if i in (-1,1)])
self.available_info_len=sum_len-zero_len-one_len # 不是特别可靠
print ("Load>> 大约可嵌入",sum_len-zero_len-int(one_len/2),'bits')
print ("Load>> 最少可嵌入",self.available_info_len,'bits\n')
def _write(self,index,data):
origin=self.sequence_after_dct[index]
if origin == 0:
return False
elif origin == 1 and data==0:
self.sequence_after_dct[index]=0
return False
elif origin == -1 and data==1:
self.sequence_after_dct[index]=0
return False
lower_bit=origin%2
if origin >0:
if lower_bit!=data:
self.sequence_after_dct[index]=origin-1
else:
if lower_bit==data:
self.sequence_after_dct[index]=origin+1
return True
def _read(self,index):
if self.sequence_after_dct[index] >0:
return self.sequence_after_dct[index]%2
elif self.sequence_after_dct[index]<0:
return (self.sequence_after_dct[index]+1)%2
else:
return None
if __name__=="__main__":
jsteg=Jsteg()
f3=F3()
f4=F4()
# 写
sequence_after_dct=DCT.after_dct
jsteg.set_sequence_after_dct(sequence_after_dct)
f3.set_sequence_after_dct(sequence_after_dct)
f4.set_sequence_after_dct(sequence_after_dct)
a={0:0,1:0,2:0,3:0,4:0,5:0,6:0,7:0,8:0,-1:0,-2:0,-3:0,-4:0,-5:0,-6:0,-7:0,-8:0}
for i in sequence_after_dct:
if i in a:
a[i]+=1
print("JPEG的DCT系数")
print(a)
info1=[int(i+0.5) for i in np.random.rand(200000)]
print("Jsteg begin writing!")
print(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>")
jsteg.write(info1)
print("F3steg begin writing!")
print(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>")
f3.write(info1)
print("F4steg begin writing!")
print(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>")
f4.write(info1)
'''
# 读
sequence_after_dct2=jsteg.get_sequence_after_dct()
sequence_after_dct3=f3.get_sequence_after_dct()
sequence_after_dct4=f4.get_sequence_after_dct()
jsteg.set_sequence_after_dct(sequence_after_dct2)
f3.set_sequence_after_dct(sequence_after_dct3)
f4.set_sequence_after_dct(sequence_after_dct4)
info2=jsteg.read()
info3=f3.read()
info4=f4.read()
'''