An Algorithm-Bug ! (on absolution and clipping)

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1 parent 4a20967b
Showing 6 changed files with 23 additions and 14 deletions Show diff stats
msteg/__init__.pyc
msteg/steganalysis/MPB.py
msteg/steganalysis/MPB.pyc
msteg/steganography/F3.pyc
msteg/steganography/LSB.pyc
res/lopez5.jpg
@@ -7,9 +7,11 @@ import time
 import math
 import numpy as np
  
-from .. import *
-from ...mjpeg import Jpeg,colorMap
-from ...common import *
+# from .. import *
+import mjpeg
+from msteg import *
+from mjpeg import Jpeg, colorMap
+from common import *
  
 import csv
 import json
@@ -43,14 +45,14 @@ class MPB(StegBase):
         :param T: signed integer, usually 1~7
         :return: TPM - 3-D tensor, numpy array of size (2*T+1, 2*T+1, 4)
         """
-        ciq = np.absolute(ciq).clip(0, T)
+        ciq = np.absolute(ciq)
         TPM = np.zeros((2 * T + 1, 2 * T + 1, 4), np.float64)
         # Fh = np.diff(ciq, axis=-1)
         # Fv = np.diff(ciq, axis=0)
-        Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
-        Fv = ciq[:-1, :-1] - ciq[1:, :-1]
-        Fd = ciq[:-1, :-1] - ciq[1:, 1:]
-        Fm = ciq[:-1, 1:] - ciq[1:, :-1]
+        Fh = (ciq[:-1, :-1] - ciq[:-1, 1:]).clip(-T, T)
+        Fv = (ciq[:-1, :-1] - ciq[1:, :-1]).clip(-T, T)
+        Fd = (ciq[:-1, :-1] - ciq[1:, 1:]).clip(-T, T)
+        Fm = (ciq[:-1, 1:] - ciq[1:, :-1]).clip(-T, T)
  
         Fh1 = Fh[:-1, :-1]
         Fh2 = Fh[:-1, 1:]
@@ -101,14 +103,21 @@ class MPB(StegBase):
  
  
         # timer = Timer()
-        ciq = np.absolute(ciq).clip(0, T)
+        # ciq = np.absolute(ciq).clip(0, T) # Fool !!!
+        ciq = np.absolute(ciq)
         TPM = np.zeros((2 * T + 1, 2 * T + 1, 4), np.float64)
         # Fh = np.diff(ciq, axis=-1)
         # Fv = np.diff(ciq, axis=0)
-        Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
-        Fv = ciq[:-1, :-1] - ciq[1:, :-1]
-        Fd = ciq[:-1, :-1] - ciq[1:, 1:]
-        Fm = ciq[:-1, 1:] - ciq[1:, :-1]
+
+        # Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
+        # Fv = ciq[:-1, :-1] - ciq[1:, :-1]
+        # Fd = ciq[:-1, :-1] - ciq[1:, 1:]
+        # Fm = ciq[:-1, 1:] - ciq[1:, :-1]
+
+        Fh = (ciq[:-1, :-1] - ciq[:-1, 1:]).clip(-T, T)
+        Fv = (ciq[:-1, :-1] - ciq[1:, :-1]).clip(-T, T)
+        Fd = (ciq[:-1, :-1] - ciq[1:, 1:]).clip(-T, T)
+        Fm = (ciq[:-1, 1:] - ciq[1:, :-1]).clip(-T, T)
  
         Fh1 = Fh[:-1, :-1].ravel()
         Fh2 = Fh[:-1, 1:].ravel()
@@ -135,7 +144,7 @@ class MPB(StegBase):
         # 1.459668s
         # timer.mark()
         # for i in range(len(Fh1)):
-        #     TPM[Fh1[i], Fh2[i], 0] += 1
+        # TPM[Fh1[i], Fh2[i], 0] += 1
         # for i in range(len(Fv1)):
         #     TPM[Fv1[i], Fv2[i], 1] += 1
         # for i in range(len(Fd1)):
...	...	@@ -7,9 +7,11 @@ import time
7	7	import math
8	8	import numpy as np
9	9
10		-from .. import *
11		-from ...mjpeg import Jpeg,colorMap
12		-from ...common import *
	10	+# from .. import *
	11	+import mjpeg
	12	+from msteg import *
	13	+from mjpeg import Jpeg, colorMap
	14	+from common import *
13	15
14	16	import csv
15	17	import json
...	...	@@ -43,14 +45,14 @@ class MPB(StegBase):
43	45	:param T: signed integer, usually 1~7
44	46	:return: TPM - 3-D tensor, numpy array of size (2T+1, 2T+1, 4)
45	47	"""
46		- ciq = np.absolute(ciq).clip(0, T)
	48	+ ciq = np.absolute(ciq)
47	49	TPM = np.zeros((2 * T + 1, 2 * T + 1, 4), np.float64)
48	50	# Fh = np.diff(ciq, axis=-1)
49	51	# Fv = np.diff(ciq, axis=0)
50		- Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
51		- Fv = ciq[:-1, :-1] - ciq[1:, :-1]
52		- Fd = ciq[:-1, :-1] - ciq[1:, 1:]
53		- Fm = ciq[:-1, 1:] - ciq[1:, :-1]
	52	+ Fh = (ciq[:-1, :-1] - ciq[:-1, 1:]).clip(-T, T)
	53	+ Fv = (ciq[:-1, :-1] - ciq[1:, :-1]).clip(-T, T)
	54	+ Fd = (ciq[:-1, :-1] - ciq[1:, 1:]).clip(-T, T)
	55	+ Fm = (ciq[:-1, 1:] - ciq[1:, :-1]).clip(-T, T)
54	56
55	57	Fh1 = Fh[:-1, :-1]
56	58	Fh2 = Fh[:-1, 1:]
...	...	@@ -101,14 +103,21 @@ class MPB(StegBase):
101	103
102	104
103	105	# timer = Timer()
104		- ciq = np.absolute(ciq).clip(0, T)
	106	+ # ciq = np.absolute(ciq).clip(0, T) # Fool !!!
	107	+ ciq = np.absolute(ciq)
105	108	TPM = np.zeros((2 * T + 1, 2 * T + 1, 4), np.float64)
106	109	# Fh = np.diff(ciq, axis=-1)
107	110	# Fv = np.diff(ciq, axis=0)
108		- Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
109		- Fv = ciq[:-1, :-1] - ciq[1:, :-1]
110		- Fd = ciq[:-1, :-1] - ciq[1:, 1:]
111		- Fm = ciq[:-1, 1:] - ciq[1:, :-1]
	111	+
	112	+ # Fh = ciq[:-1, :-1] - ciq[:-1, 1:]
	113	+ # Fv = ciq[:-1, :-1] - ciq[1:, :-1]
	114	+ # Fd = ciq[:-1, :-1] - ciq[1:, 1:]
	115	+ # Fm = ciq[:-1, 1:] - ciq[1:, :-1]
	116	+
	117	+ Fh = (ciq[:-1, :-1] - ciq[:-1, 1:]).clip(-T, T)
	118	+ Fv = (ciq[:-1, :-1] - ciq[1:, :-1]).clip(-T, T)
	119	+ Fd = (ciq[:-1, :-1] - ciq[1:, 1:]).clip(-T, T)
	120	+ Fm = (ciq[:-1, 1:] - ciq[1:, :-1]).clip(-T, T)
112	121
113	122	Fh1 = Fh[:-1, :-1].ravel()
114	123	Fh2 = Fh[:-1, 1:].ravel()
...	...	@@ -135,7 +144,7 @@ class MPB(StegBase):
135	144	# 1.459668s
136	145	# timer.mark()
137	146	# for i in range(len(Fh1)):
138		- # TPM[Fh1[i], Fh2[i], 0] += 1
	147	+ # TPM[Fh1[i], Fh2[i], 0] += 1
139	148	# for i in range(len(Fv1)):
140	149	# TPM[Fv1[i], Fv2[i], 1] += 1
141	150	# for i in range(len(Fd1)):
...	...