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复现代码
注：
代码不可商用！
代码不可商用！
代码不可商用！
from skimage import io
import matplotlib.pyplot as plt
import numpy as np
class Test:
def __init__(self):
self.data = np.array(
[[251, 252, 253, 253],
[252, 254, 252, 251],
[252, 252, 252, 252],
[252, 253, 252, 255]]
)
def int2bin(x, length):
string = ''
while x != 0:
string = str(x % 2) + string
x = x // 2
if len(string) > length:
raise Exception("The length of x is longer actually!")
elif len(string) < length:
return '0' * (length - len(string)) + string
else:
return string
def countMiu(x1, x2, x3, x4):
delta = []
miu = 0
x1 = float(x1)
x2 = float(x2)
x3 = float(x3)
x4 = float(x4)
if x4 != -1:
delta.append(abs(x1 - x2))
delta.append(abs(x2 - x3))
delta.append(abs(x3 - x4))
delta.append(abs(x4 - x1))
deltaAvg = (delta[0] + delta[1] + delta[2] + delta[3]) / 4
for i in range(4):
miu += (delta[i] - deltaAvg) ** 2
return miu / 4
elif x3 != -1:
delta.append(abs(x1 - x2))
delta.append(abs(x2 - x3))
delta.append(abs(x3 - x1))
deltaAvg = (delta[0] + delta[1] + delta[2]) / 3
for i in range(3):
miu += (delta[i] - deltaAvg) ** 2
return miu / 3
else:
return 10 ** 5
def countPrdMiu(img, row, column):
if row == 0 and column == 0:
prd = (int(img[0][1]) + int(img[1][0])) // 2
miu = countMiu(int(img[0][1]), int(img[1][0]), -1, -1)
elif row == (img.shape[0] - 1) and column == (img.shape[1] - 1):
prd = (int(img[img.shape[0] - 2][img.shape[0] - 1]) + int(img[img.shape[0] - 1][img.shape[1] - 2])) // 2
miu = countMiu(int(img[img.shape[0] - 2][img.shape[0] - 1]), int(img[img.shape[0] - 1][img.shape[1] - 2]), -1,
-1)
elif row == 0:
prd = (int(img[0][column - 1]) + int(img[0][column + 1]) + int(img[1][column])) // 3
miu = countMiu(int(img[0][column - 1]), int(img[0][column + 1]), int(img[1][column]), -1)
elif row == img.shape[0] - 1:
prd = (int(img[row][column - 1]) + int(img[row][column + 1]) + int(img[row - 1][column])) // 3
miu = countMiu(int(img[row][column - 1]), int(img[row][column + 1]), int(img[row - 1][column]), -1)
elif column == 0:
prd = (int(img[row - 1][0]) + int(img[row + 1][0]) + int(img[row][1])) // 3
miu = countMiu(int(img[row - 1][0]), int(img[row + 1][0]), int(img[row][1]), -1)
elif column == img.shape[1] - 1:
prd = (int(img[row - 1][column]) + int(img[row + 1][column]) + int(img[row][column - 1])) // 3
miu = countMiu(int(img[row - 1][column]), int(img[row + 1][column]), int(img[row][column - 1]), -1)
else:
prd = (int(img[row - 1][column]) + int(img[row + 1][column])
+ int(img[row][column - 1]) + int(img[row][column + 1])) // 4
miu = countMiu(int(img[row - 1][column]), int(img[row + 1][column]),
int(img[row][column - 1]), int(img[row][column + 1]))
return prd, miu
def HistogramShift(origin, prd, Tn, Tp, b):
d = origin - prd
if Tn <= d <= Tp:
D = 2 * d + b
elif d > Tp:
D = d + Tp + 1
else:
D = d + Tn
return D
def judgeTwiceFlow(origin, prd, Tn, Tp):
if origin < prd:
origin2 = prd + HistogramShift(origin, prd, Tn, Tp, 0)
if origin2 < 0:
return 1
else:
if prd + HistogramShift(origin2, prd, Tn, Tp, 0) < 0:
return 0
else:
return -1
else:
origin2 = prd + HistogramShift(origin, prd, Tn, Tp, 1)
if origin2 > 255:
return 1
else:
if prd + HistogramShift(origin2, prd, Tn, Tp, 1) > 255:
return 0
else:
return -1
def embed(img, row, column, origin, prd, Tn, Tp, b):
img[row][column] = prd + HistogramShift(origin, prd, Tn, Tp, b)
def countPosition(img, place):
row = place // img.shape[1]
if img.shape[1] % 2 == 1:
column = place % img.shape[1]
elif row % 2 == 0:
column = place % img.shape[1]
else:
column = place % img.shape[1] + 1
return row, column
def embedOnePattern(place, Tn, Tp, P, processed):
encrypted = processed
Slsb = ''
head = int2bin(-Tn, 7) + int2bin(Tp, 7) + int2bin(len(P), 20)
row_dic = []
row_dic_list = []
row_dic_list_sorted = []
for z in range(encrypted.shape[0]):
row_dic.append({})
row_dic_list.append(z)
row_dic_list_sorted.append(z)
start = 1
locationMap = ''
needDot = True
while place < img.shape[0] * img.shape[1]:
row, column = countPosition(img, place)
if (place + 2) // img.shape[1] == row:
prd, miu = countPrdMiu(img, row, column)
origin = img[row][column]
row_dic[row][row, column, origin, prd] = miu
else:
prd, miu = countPrdMiu(img, row, column)
origin = img[row][column]
row_dic[row][row, column, origin, prd] = miu
row_dic_list[row] = list(zip(row_dic[row].values(), row_dic[row].keys()))
row_dic_list_sorted[row] = sorted(row_dic_list[row])
# 没有放在外面是因为接着判断为换行，在处理这个行尾的时候，用这个固定的row，直接sorting完这一行
for i in range(len(row_dic_list_sorted[row])):
# 标记出位图
if start == 1 and judgeTwiceFlow(row_dic_list_sorted[row][i][1][2],
row_dic_list_sorted[row][i][1][3], Tn, Tp) >= 0:
continue
else:
start = 0
if judgeTwiceFlow(row_dic_list_sorted[row][i][1][2],
row_dic_list_sorted[row][i][1][3], Tn, Tp) != -1:
locationMap += str(judgeTwiceFlow(row_dic_list_sorted[row][i][1][2],
row_dic_list_sorted[row][i][1][3], Tn, Tp))
place += 2
start = 1
embedded_message = locationMap
# 利用之前算出来的sorting顺序，直接进行嵌入embed
for x in range(img.shape[0]):
for y in range(len(row_dic_list_sorted[x])):
if x * img.shape[1] + y < 34:
encrypted[row_dic_list_sorted[x][y][1][0]][row_dic_list_sorted[x][y][1][1]] = \
img[row_dic_list_sorted[x][y][1][0]][row_dic_list_sorted[x][y][1][1]] // 2 * 2 + int(head[0])
Slsb += str(img[row_dic_list_sorted[x][y][1][0]][row_dic_list_sorted[x][y][1][1]] % 2)
head = head[1:]
else:
if start == 1:
embedded_message = locationMap + Slsb + P
start = 0
d = row_dic_list_sorted[x][y][1][2] - row_dic_list_sorted[x][y][1][3]
if Tn <= d <= Tp and len(embedded_message) > 0:
embed(encrypted, row_dic_list_sorted[x][y][1][0], row_dic_list_sorted[x][y][1][1],
row_dic_list_sorted[x][y][1][2], row_dic_list_sorted[x][y][1][3], Tn, Tp,
int(embedded_message[0]))
embedded_message = embedded_message[1:]
else:
embed(encrypted, row_dic_list_sorted[x][y][1][0], row_dic_list_sorted[x][y][1][1],
row_dic_list_sorted[x][y][1][2], row_dic_list_sorted[x][y][1][3], Tn, Tp,
0) # 超过界限就嵌入0
if len(embedded_message) > len(P):
raise Exception("Didn't finish embedding lacation map and Slsb!")
if len(embedded_message) == 0:
print("No need to embed Dot set!")
needDot = False
return encrypted, embedded_message, needDot
def encode(img, Tn, Tp, P):
'''
Encode the original imagine.
:param img: original imagine
:param Tn: start threshold
:param Tp: end threshold
:param P: payload
:return: The encrypted imagine and the bool value sign whether need Dot pattern encoding.
'''
if img.shape[0] * img.shape[1] < 34 * 4:
raise Exception("The imagine is too small!")
if Tn >= 0:
raise Exception("Tn need to be negative!")
if Tp < 0:
raise Exception("Tp need to be positive!")
encrypted = np.array(img)
encrypted, embedded_message, needDot = embedOnePattern(0, Tn, Tp, P, encrypted)
if needDot is True:
encrypted, embedded_message, needDot = embedOnePattern(1, Tn, Tp, P, encrypted)
if len(embedded_message) > 0:
raise Exception("Length of P,", len(P), ", is much more than this picture can be embedded!")
else:
return encrypted, True
else:
return encrypted, False
def Slsb2int(string):
if len(string) != 34:
raise Exception("Given string's length isn't 34!")
T = [0, 0]
P = 0
cut = [string[0:7], string[7:14], string[14: 34]]
for i in range(2):
for j in range(7):
T[i] += int(cut[i][-1]) * 2 ** j
cut[i] = cut[i][0:-1]
for j in range(20):
P += int(cut[2][-1]) * 2 ** j
cut[2] = cut[2][0:-1]
return T[0], T[1], P
def countPattenNum(isOdd, place, img):
if isOdd is False:
return img.shape[0] * img.shape[1] // 2
if isOdd is True:
if place == 0:
return img.shape[0] * img.shape[1] // 2 + 1
else:
return img.shape[0] * img.shape[1] // 2
def judgeOnceFlow(origin, prd, Tn, Tp):
if origin < prd:
if prd + HistogramShift(origin, prd, Tn, Tp, 0) < 0:
return True
else:
return False
else:
if prd + HistogramShift(origin, prd, Tn, Tp, 1) > 255:
return True
else:
return False
def extractPixel(origin, prd):
result = (origin - prd) % 2
return result
def decodeShift(origin, prd, Tn, Tp):
D = origin - prd
if 2 * Tn <= D <= 2 * Tp + 1:
d = D // 2
elif D > 2 * Tp + 1:
d = D - Tp - 1
else:
d = D - Tn
return d
def restoreImg(needResumed, message, bitNum, row_dic_list_sorted, Tn, Tp):
processed = needResumed
start = 1
bitPosition = 0
Slsb = message[bitNum:bitNum + 34]
for i in range(processed.shape[0]):
for j in range(len(row_dic_list_sorted[i])):
if i * processed.shape[0] + j < 34:
processed[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] = \
processed[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] - \
processed[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] % 2 + int(Slsb[0])
Slsb = Slsb[1:]
else:
if start == 1 and judgeOnceFlow(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3], Tn, Tp) is True:
continue
else:
start = 0
if judgeOnceFlow(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3], Tn, Tp) is False:
processed[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] \
= row_dic_list_sorted[i][j][1][3] \
+ decodeShift(row_dic_list_sorted[i][j][1][2], row_dic_list_sorted[i][j][1][3], Tn, Tp)
else:
if message[bitPosition] == 0:
processed[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] \
= row_dic_list_sorted[i][j][1][3] \
+ decodeShift(row_dic_list_sorted[i][j][1][2], row_dic_list_sorted[i][j][1][3], Tn, Tp)
else:
pass
bitPosition += 1
return processed
def decodeOnePattern(place, encrypted):
resumed = encrypted
odd = False
if encrypted.shape[0] % 2 != 0 and encrypted.shape[1] % 2 != 0:
odd = True
head = ''
start = 1
startRow = 0
message = ''
bitPosition = 0
row_dic = []
row_dic_list = []
row_dic_list_sorted = []
for z in range(encrypted.shape[0]):
row_dic.append({})
row_dic_list.append(z)
row_dic_list_sorted.append(z)
for i in range(countPattenNum(odd, place, encrypted)):
row, column = countPosition(encrypted, place)
if (place + 2) // encrypted.shape[1] == row:
prd, miu = countPrdMiu(encrypted, row, column)
modified = encrypted[row][column]
row_dic[row][row, column, modified, prd] = miu
else:
prd, miu = countPrdMiu(encrypted, row, column)
modified = encrypted[row][column]
row_dic[row][row, column, modified, prd] = miu
row_dic_list[row] = list(zip(row_dic[row].values(), row_dic[row].keys()))
row_dic_list_sorted[row] = sorted(row_dic_list[row])
place += 2
place = 0
needBreak = False
for i in range(encrypted.shape[0]):
for j in range(len(row_dic_list_sorted[i])):
if i * encrypted.shape[1] + j >= 34:
needBreak = True
if needBreak is True:
break
head += str(encrypted[row_dic_list_sorted[i][j][1][0]][row_dic_list_sorted[i][j][1][1]] % 2)
if needBreak is True:
break
Tn, Tp, P = Slsb2int(head)
Tn = -Tn
if Tn >= 0:
raise Exception("The extracted Tn isn't negative!")
if Tp < 0:
raise Exception("The extracted Tp isn't positive!")
for i in range(encrypted.shape[0]):
for j in range(len(row_dic_list_sorted[i])):
if i * encrypted.shape[1] + j < 34:
pass
else:
if start == 1 and judgeOnceFlow(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3], Tn, Tp) is True:
continue
else:
start = 0
if judgeOnceFlow(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3], Tn, Tp) is False:
D = row_dic_list_sorted[i][j][1][2] - row_dic_list_sorted[i][j][1][3]
if 2 * Tn <= D <= 2 * Tp + 1:
message += str(extractPixel(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3]))
else:
if message[bitPosition] == 0:
D = row_dic_list_sorted[i][j][1][2] - row_dic_list_sorted[i][j][1][3]
if 2 * Tn <= D <= 2 * Tp + 1:
message += str(extractPixel(row_dic_list_sorted[i][j][1][2],
row_dic_list_sorted[i][j][1][3]))
bitPosition += 1
elif message[bitPosition] == 1:
bitPosition += 1
resumed = restoreImg(resumed, message, bitPosition, row_dic_list_sorted, Tn, Tp)
info = message[bitPosition + 34:bitPosition + 34 + P]
return resumed, info
# 还有第二次嵌入要处理一下，到时候写
def decode(encrypted, needDot):
'''
Decode the encrypted imagine.
:param encrypted: the encrypted imagine
:param needDot: whether you need decoding Dot set or not
:return: The original imagine and the secret information.
'''
if img.shape[0] * img.shape[1] < 34 * 4:
raise Exception("The imagine is too small!")
if needDot is False:
imagine, info = decodeOnePattern(0, encrypted)
else:
encrypted1, info1 = decodeOnePattern(1, encrypted)
imagine, info2 = decodeOnePattern(0, encrypted1)
info = info1 + info2
return imagine, info
if __name__ == "__main__":
img = io.imread("../img/lena_gray_512.tif") # 在这里放你要处理的图像 place your imagine here
# img = Test().data
# print(img)
encrypted, needDot = encode(img, -1, 0, '100000')
print("need Dot:", needDot)
resumedImg, info = decode(encrypted, needDot)
print("The secret info is:", info)
print("img == resumedImg:")
print(img == resumedImg)
plt.set_cmap(cmap="gray")
plt.subplot(131)
plt.imshow(img)
plt.title("Original imagery")
plt.subplot(132)
plt.imshow(encrypted)
plt.title("Encrypted imagery")
plt.subplot(133)
plt.imshow(resumedImg)
plt.title("Resumed imagery")
plt.show()
结果如下：
代码只写了处理嵌入Cross集的，如果嵌入信息超过Cross集容量上限而要用到Dot集嵌入的我还没写完，看以后有机会补充没有。