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tech
n
iq
u
es
h
a
v
e
b
ee
n
p
r
o
p
o
s
ed
b
y
v
ar
i
o
u
s
r
esear
ch
er
s
to
m
a
in
ta
i
n
h
ig
h
q
u
alit
y
o
f
s
te
g
o
i
m
ag
e
f
o
r
a
g
i
v
e
n
e
m
b
ed
d
in
g
ca
p
ac
it
y
a
f
ter
s
ec
r
et
d
ata
e
m
b
ed
d
in
g
,
f
o
r
e
x
a
m
p
le
in
[
6
]
an
d
[
7
]
.
I
n
[
8
]
,
a
Di
f
f
er
e
n
ce
E
x
p
an
s
io
n
(
DE
)
b
ased
d
ata
h
i
d
in
g
a
lg
o
r
it
h
m
w
a
s
p
r
o
p
o
s
ed
.
A
s
o
n
e
o
f
s
p
atial
d
o
m
ai
n
tech
n
iq
u
e
s
,
th
is
alg
o
r
ith
m
e
x
p
lo
its
r
ed
u
n
d
an
c
y
i
n
f
o
r
m
atio
n
b
et
w
ee
n
p
ix
els
to
h
id
e
a
s
ec
r
et
m
es
s
a
g
e.
I
n
[
9
]
,
a
h
ig
h
e
m
b
ed
d
in
g
ca
p
ac
it
y
f
o
r
lo
w
d
is
to
r
tio
n
o
f
h
o
s
t
i
m
ag
e
w
as
d
ev
elo
p
ed
w
h
er
e
a
n
R
GB
i
m
a
g
e
w
as
u
s
ed
a
n
d
s
ec
r
et
b
its
ar
e
in
s
er
ted
b
ased
o
n
p
ix
el
b
lo
c
k
clas
s
i
f
icatio
n
.
I
n
g
en
er
al,
it
is
a
c
h
alle
n
g
i
n
g
p
r
o
b
lem
to
d
ev
elo
p
a
d
ata
h
id
in
g
m
et
h
o
d
th
at
s
u
p
p
o
r
ts
b
o
th
h
ig
h
v
i
s
u
al
q
u
alit
y
an
d
p
ay
lo
ad
ca
p
ac
ity
b
ec
a
u
s
e
th
ese
t
w
o
f
ac
to
r
s
ar
e
in
v
er
s
el
y
p
r
o
p
o
r
tio
n
al
[
1
0
]
,
[
1
1
]
.
I
n
th
i
s
p
ap
er
,
w
e
p
r
o
p
o
s
e
a
n
e
w
b
ase
p
o
in
t
i
n
th
e
co
m
p
u
tatio
n
o
f
d
if
f
er
e
n
ce
s
b
et
w
ee
n
p
ix
els
o
f
i
m
a
g
e
i
n
co
m
b
i
n
atio
n
w
it
h
a
n
e
w
r
ed
u
ce
d
d
i
f
f
er
e
n
ce
e
x
p
an
s
io
n
to
m
i
n
i
m
ize
t
h
e
d
i
f
f
er
en
c
e
b
ef
o
r
e
s
ec
r
et
d
ata
e
m
b
ed
d
in
g
p
r
o
ce
s
s
ta
k
es p
lac
e.
Hen
ce
,
th
e
q
u
ali
t
y
o
f
s
te
g
o
im
ag
e
i
s
en
h
a
n
ce
d
f
o
r
a
g
i
v
en
p
ay
lo
ad
ca
p
ac
i
t
y
.
T
h
is
p
ap
er
is
o
r
g
an
ized
in
5
s
ec
tio
n
s
.
I
n
Sectio
n
1
,
w
e
g
iv
e
a
n
o
v
er
v
ie
w
o
f
t
h
e
r
esear
ch
p
r
o
b
le
m
s
.
I
n
Sectio
n
2
,
w
e
d
escr
ib
e
th
e
l
it
er
atu
r
e
s
tu
d
y
o
n
d
ata
h
id
i
n
g
b
ased
o
n
d
if
f
er
en
ce
e
x
p
an
s
io
n
m
et
h
o
d
.
Sectio
n
3
ex
p
lain
s
th
e
p
r
o
p
o
s
ed
m
e
th
o
d
w
h
ile
i
n
Secti
o
n
4
,
th
e
ev
al
u
atio
n
o
f
t
h
e
m
et
h
o
d
an
d
its
r
e
s
u
lt
s
ar
e
p
r
esen
ted
w
h
ic
h
ar
e
t
h
e
n
co
m
p
ar
ed
w
i
th
p
r
ev
io
u
s
m
eth
o
d
s
.
W
e
en
d
u
p
t
h
e
w
o
r
k
i
n
Sectio
n
5
b
y
p
r
o
v
id
i
n
g
t
h
e
co
n
clu
s
io
n
r
e
m
ar
k
s
a
n
d
th
e
f
u
tu
r
e
w
o
r
k
s
.
2.
RE
S
E
ARCH
M
E
T
H
O
D
I
n
[
8
]
,
a
d
ata
h
id
in
g
alg
o
r
it
h
m
t
h
at
u
s
es
d
if
f
er
e
n
ce
ex
p
an
s
io
n
w
as
p
r
o
p
o
s
ed
.
T
h
e
alg
o
r
ith
m
h
id
e
s
s
ec
r
et
in
f
o
r
m
atio
n
w
it
h
in
th
e
d
if
f
er
e
n
ce
b
et
w
ee
n
t
w
o
ad
j
ac
en
t
p
ix
el
s
.
Her
e,
th
e
d
if
f
er
en
ce
an
d
av
er
ag
e
ar
e
co
m
p
u
ted
th
e
n
a
m
es
s
a
g
e
is
e
m
b
ed
d
ed
w
it
h
in
th
e
d
i
f
f
er
en
c
e
w
h
ile
t
h
e
a
v
er
ag
e
i
s
u
s
ed
d
u
r
in
g
t
h
e
cr
ea
tio
n
o
f
s
teg
o
p
i
x
els
a
n
d
i
n
t
h
e
ex
tr
ac
t
io
n
p
r
o
ce
s
s
.
T
h
e
alg
o
r
ith
m
is
p
r
esen
ted
as
f
o
llo
w
.
S
u
p
p
o
s
e,
th
e
co
v
er
i
m
a
g
e
i
s
d
iv
id
ed
in
to
b
lo
ck
s
co
m
p
r
is
i
n
g
t
w
o
s
u
cc
e
s
s
i
v
e
p
ix
el
s
.
L
et
b
e
th
e
d
if
f
er
e
n
ce
w
it
h
o
u
t
s
ec
r
et
m
es
s
ag
e
a
n
d
d
if
f
er
e
n
ce
w
it
h
s
ec
r
et
m
es
s
ag
e
e
m
b
ed
d
ed
,
r
esp
ec
tiv
el
y
;
w
h
ile
is
t
h
e
p
i
x
el
wh
o
s
e
d
if
f
er
e
n
ce
co
n
tain
s
th
e
s
ec
r
et
d
ata
.
I
n
th
e
p
ap
er
,
tak
es
t
h
e
v
al
u
e
0
to
1
b
ec
au
s
e
a
b
lo
ck
is
co
m
p
o
s
e
d
o
f
t
w
o
p
ix
el
s
an
d
o
n
l
y
a
s
in
g
le
d
i
f
f
er
e
n
ce
is
co
m
p
u
ted
w
h
ich
m
ea
n
s
f
o
r
d
if
f
er
en
ce
i
s
s
u
b
j
ec
ted
to
b
e
1
.
T
h
e
in
d
ex
is
a
n
in
d
ex
f
o
r
s
ec
r
et
m
e
s
s
a
g
e
th
at
tak
es
1
b
ec
au
s
e
o
n
l
y
a
s
i
n
g
le
b
it
f
r
o
m
a
s
ec
r
et
m
ess
a
g
e
is
e
m
b
ed
d
ed
w
i
th
i
n
a
d
if
f
er
e
n
ce
.
I
n
ad
d
itio
n
,
̅
d
en
o
tes
th
e
a
v
er
ag
e
b
e
t
w
ee
n
t
h
o
s
e
t
w
o
p
i
x
els.
T
h
e
s
te
g
o
p
i
x
els
ar
e
o
b
tain
ed
th
r
o
u
g
h
t
h
e
p
r
o
ce
s
s
es
f
r
o
m
E
q
u
atio
n
s
(
1
)
to
(
5
)
.
(
1
)
̅
⌊
⌋
(
2
)
(
3
)
̅
⌊
⌋
(
4
)
̅
⌊
⌋
(
5
)
I
n
t
h
e
ex
tr
ac
tio
n
p
r
o
ce
s
s
,
t
h
e
d
if
f
er
e
n
ce
b
et
w
ee
n
s
teg
o
p
i
x
e
ls
is
co
m
p
u
ted
.
T
h
en
t
h
e
lea
s
t
s
ig
n
i
f
ica
n
t
b
it
f
u
n
ctio
n
is
ap
p
lied
to
ex
tr
ac
t
th
e
s
ec
r
et
m
ess
a
g
e.
T
h
er
ea
f
ter
,
th
e
o
r
ig
in
al
d
if
f
er
en
ce
is
c
alcu
lated
w
h
ic
h
in
tu
r
n
is
u
s
ed
to
co
m
p
u
te
o
r
ig
in
a
l
p
ix
e
ls
.
F
ir
s
t,
t
h
e
d
i
f
f
er
en
ce
b
et
w
ee
n
s
te
g
o
p
ix
e
ls
i
s
ca
lcu
lated
u
s
i
n
g
.
Seco
n
d
l
y
,
th
e
s
ec
r
et
m
es
s
ag
e
is
ta
k
en
f
r
o
m
ea
ch
o
f
th
e
d
if
f
er
en
ce
s
as
s
h
o
w
n
i
n
.
Af
ter
g
etti
n
g
th
e
s
ec
r
et
m
es
s
ag
e,
t
h
e
o
r
ig
i
n
al
d
i
f
f
er
en
ce
i
s
o
b
tain
ed
b
y
u
s
i
n
g
E
q
u
atio
n
(
6
)
w
h
er
e
th
e
d
if
f
er
en
ce
co
m
p
u
te
d
f
r
o
m
t
h
e
s
te
g
o
i
m
ag
e
i
s
r
ig
h
t
s
h
if
ted
.
T
h
e
o
r
ig
in
al
p
ix
el
ar
e
g
iv
en
b
ac
k
b
y
u
s
i
n
g
E
q
u
atio
n
s
(
7
)
an
d
(
8
)
w
h
er
e
th
e
f
o
r
m
er
is
u
s
ed
to
co
m
p
u
te
t
h
e
o
r
ig
in
a
l
f
ir
s
t
p
ix
e
l
w
h
ile
t
h
e
latter
is
u
s
ed
to
g
et
th
e
s
ec
o
n
d
o
n
e.
T
h
is
d
e
m
o
n
s
tr
ate
s
th
at
d
if
f
er
en
ce
ex
p
an
s
io
n
i
s
a
r
ev
er
s
ib
le
d
ata
h
id
in
g
m
et
h
o
d
w
h
er
e
b
o
th
s
ec
r
et
m
e
s
s
a
g
e
an
d
co
v
er
ar
e
ex
tr
ac
ted
an
d
r
ec
o
v
er
ed
r
esp
ec
tiv
el
y
w
it
h
o
u
t a
n
y
d
a
m
a
g
e.
⌊
⌋
(
6
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
4
,
A
u
g
u
s
t 2
0
1
8
:
2
4
6
8
–
2
4
7
6
2470
̅
⌊
⌋
(
7
)
̅
⌊
⌋
(
8
)
T
h
e
m
et
h
o
d
s
u
f
f
er
s
to
u
n
d
er
f
l
o
w
o
r
o
v
er
f
lo
w
i
s
s
u
e.
I
n
all
g
r
a
y
s
ca
le
i
m
ag
e
s
,
o
v
er
f
lo
w
h
ap
p
en
s
if
t
h
e
r
esu
lted
p
ix
e
l
v
al
u
e
i
s
g
r
ea
ter
th
a
n
2
5
5
,
w
h
ile
u
n
d
er
f
lo
w
h
ap
p
en
s
if
it
is
les
s
th
a
n
0
.
T
o
en
s
u
r
e
t
h
at
th
e
p
r
o
b
l
e
m
is
av
o
id
ed
,
th
e
E
q
u
atio
n
(
9
)
is
v
e
r
f
ied
.
≤
̅
⌊
⌋
≤
≤
̅
⌊
⌋
≤
(
9
)
I
n
th
i
s
m
eth
o
d
,
a
p
ix
el
b
lo
ck
m
a
y
h
a
v
e
o
n
e
o
f
th
r
ee
p
o
s
s
ib
l
e
ch
ar
ac
ter
is
tic
s
:
ex
p
a
n
d
ab
le,
ch
an
g
ea
b
le
o
r
n
o
n
-
c
h
a
n
g
ea
b
le.
Her
e,
a
b
l
o
ck
is
co
n
s
id
er
ed
as
ex
p
a
n
d
ab
le
if
E
q
u
a
tio
n
(
1
0
)
is
s
at
is
f
ied
an
d
as
c
h
an
g
ea
b
le
if
eq
u
atio
n
(
1
1
)
is
f
u
lf
i
lled
.
T
h
e
n
o
n
-
c
h
an
g
ea
b
le
b
lo
ck
s
ar
e
ig
n
o
r
ed
b
ec
au
s
e
th
e
y
ca
u
s
e
ei
th
er
an
o
v
er
f
lo
w
o
r
u
n
d
er
f
lo
w
p
r
o
b
le
m
.
Ma
n
y
al
g
o
r
ith
m
s
h
av
e
b
ee
n
p
r
o
p
o
s
e
d
to
im
p
r
o
v
e
t
h
e
alg
o
r
it
h
m
eith
er
b
y
i
n
cr
ea
s
i
n
g
qu
alit
y
o
f
s
te
g
o
i
m
a
g
e
[
1
0
]
,
p
a
y
lo
ad
ca
p
ac
it
y
[
1
2
]
,
[
1
3
]
o
r
b
o
th
[
1
4
]
,
[
1
5
]
.
|
h
n
s
i
|
≤
m
in
(
x
̅
)
x
̅
(1
0
)
|
⌊
⌋
|
≤
(
(
̅
)
)
̅
(
1
1
)
I
n
[
1
2
]
,
A
lattar
p
r
o
p
o
s
ed
a
d
ata
h
id
i
n
g
m
et
h
o
d
b
ased
o
n
q
u
ad
p
ix
els
b
lo
ck
th
at
ai
m
s
to
i
m
p
r
o
v
e
t
h
e
e
m
b
ed
d
in
g
ca
p
ac
it
y
.
T
o
m
ak
e
th
i
s
,
t
h
e
b
lo
ck
s
ize
i
n
cr
ea
s
es
f
r
o
m
1
2
to
2
2
p
ix
els.
T
h
is
ti
m
e,
th
e
m
et
h
o
d
is
ab
le
to
ca
r
r
y
t
h
r
ee
s
ec
r
et
b
it
s
i
n
a
s
in
g
le
p
i
x
el
b
lo
ck
i
n
s
tead
o
f
o
n
e
s
ec
r
et
b
it.
T
h
e
d
i
f
f
er
e
n
ce
in
te
g
er
tr
an
s
f
o
r
m
is
co
m
p
u
ted
b
y
u
s
i
n
g
E
q
u
atio
n
(
1
2
)
w
h
er
e
th
e
f
ir
s
t
d
if
f
er
en
ce
is
co
n
s
id
er
ed
as
th
e
av
er
ag
e
o
f
all
f
o
u
r
p
i
x
el
s
in
a
s
i
n
g
le
b
lo
ck
.
{
⌊
⌋
(
1
2
)
I
n
h
i
s
m
e
th
o
d
,
th
e
s
ec
r
et
d
ata
e
m
b
ed
d
in
g
i
s
p
er
f
o
r
m
ed
i
n
th
e
s
a
m
e
w
a
y
as i
n
[
8
]
ex
ce
p
t th
a
t th
er
e
ar
e
th
r
ee
d
i
f
f
er
e
n
ce
s
to
ca
r
r
y
th
r
ee
s
e
cr
et
b
its
.
T
h
er
ea
f
ter
,
t
h
e
i
n
v
er
s
e
i
n
te
g
er
s
tr
an
s
f
o
r
m
s
ch
e
m
e
to
o
b
tain
o
r
ig
i
n
al
p
i
x
els i
s
ca
lcu
lated
u
s
in
g
E
q
u
atio
n
(
1
3
)
.
{
⌊
⌋
(
1
3
)
I
n
an
o
t
h
er
r
esear
ch
d
o
n
e
to
i
m
p
r
o
v
e
t
h
e
v
is
u
al
q
u
alit
y
o
f
s
teg
o
i
m
a
g
e,
L
i
u
et
a
l
[
1
6
]
p
r
o
p
o
s
ed
to
r
ed
u
ce
th
e
d
i
f
f
er
en
ce
b
e
f
o
r
e
t
h
e
e
m
b
ed
d
i
n
g
p
r
o
ce
s
s
.
T
h
e
r
e
d
u
ctio
n
i
s
p
er
f
o
r
m
ed
if
an
d
o
n
l
y
i
f
t
h
e
d
i
f
f
er
e
n
ce
is
g
r
ea
ter
t
h
an
2
,
o
th
er
w
is
e
it
is
n
o
t r
ed
u
ce
d
,
s
ee
E
q
u
a
tio
n
(
1
4
)
w
h
er
e
is
th
e
r
ed
u
ce
d
d
i
f
f
e
r
en
ce
.
Af
ter
g
e
tti
n
g
,
th
e
e
m
b
ed
d
in
g
an
d
ex
tr
ac
tio
n
p
r
o
ce
s
s
h
a
v
e
b
ec
o
m
e
t
h
e
s
a
m
e
as
t
h
e
m
eth
o
d
p
r
o
p
o
s
ed
in
[
8
]
.
T
h
e
lo
ca
tio
n
m
ap
(
)
s
p
ec
if
ied
in
E
q
u
a
tio
n
(
1
5
)
w
as
u
s
ed
f
o
r
th
e
p
u
r
p
o
s
e
o
f
r
ev
e
r
s
ib
i
lit
y
.
{
⌊
⌋
(
1
4
)
{
⌊
⌋
⌊
⌋
⌊
⌋
(
1
5
)
A
t
th
e
r
ec
ei
v
er
s
id
e,
t
h
e
s
ec
r
e
t
m
e
s
s
a
g
e
b
its
ar
e
e
x
tr
ac
ted
f
r
o
m
th
e
e
m
b
ed
d
ed
d
if
f
er
e
n
ce
s
b
y
u
s
i
n
g
th
e
f
u
n
ctio
n
.
Ne
x
t,
t
h
e
o
r
ig
i
n
al
d
if
f
er
en
ce
i
s
r
ec
o
v
er
ed
b
y
u
s
i
n
g
E
q
u
atio
n
(
1
6
)
.
On
ce
t
h
e
v
al
u
e
h
as
b
ee
n
o
b
tain
ed
,
th
e
o
r
ig
i
n
al
p
ix
el
is
r
ec
o
v
er
ed
u
s
i
n
g
t
h
e
s
a
m
e
ex
p
r
ess
io
n
i
n
[
8
]
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
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&
C
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SS
N:
2
0
8
8
-
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P
r
o
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g
Da
ta
b
y
I
mp
r
o
vin
g
Qu
a
lity o
f S
teg
o
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ma
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b
a
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(
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ta
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b
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i
)
2471
{
⌊
⌋
⌊
⌋
(
1
6
)
I
n
[
1
7
]
,
an
im
p
r
o
v
ed
q
u
ad
an
d
R
ed
u
ce
d
Dif
f
er
e
n
ce
E
x
p
an
s
io
n
(
R
DE
)
d
ata
h
id
in
g
alg
o
r
ith
m
w
a
s
p
r
esen
ted
.
I
n
th
i
s
m
et
h
o
d
,
th
e
q
u
alit
y
o
f
s
te
g
o
i
m
ag
e
h
a
s
in
cr
ea
s
ed
d
u
e
to
f
u
r
th
er
r
ed
u
ctio
n
o
f
d
i
f
f
er
e
n
c
e
b
et
w
ee
n
ad
j
ac
en
t
p
ix
els.
I
n
a
d
d
itio
n
,
h
ig
h
p
a
y
lo
ad
ca
p
ac
ity
is
m
ai
n
tai
n
ed
.
Di
f
f
er
e
n
t
f
r
o
m
i
n
teg
er
tr
a
n
s
f
o
r
m
s
ch
e
m
e
in
[
1
2
]
an
d
[
1
8
]
,
th
e
f
ir
s
t
d
if
f
er
e
n
ce
w
a
s
p
r
o
p
o
s
ed
to
b
e
0
an
d
th
e
in
teg
er
tr
an
s
f
o
r
m
f
u
n
ctio
n
w
as
p
er
f
o
r
m
ed
u
s
i
n
g
E
q
u
atio
n
(
1
7
)
.
{
(
1
7
)
In
o
r
d
er
to
r
ed
u
ce
i
m
a
g
e
d
is
to
r
tio
n
af
ter
e
m
b
ed
d
in
g
p
r
o
ce
s
s
,
d
if
f
er
e
n
ce
r
ed
u
ctio
n
f
o
r
m
u
la
p
r
o
p
o
s
ed
in
[
1
6
]
is
i
m
p
r
o
v
ed
to
g
e
t
s
m
all
er
d
if
f
er
en
ce
s
,
a
s
d
ep
icted
i
n
E
q
u
atio
n
(
1
8
)
w
h
er
e
v
ar
ies
f
r
o
m
0
to
3
.
T
h
at
is
,
th
e
r
ed
u
ctio
n
i
s
p
er
f
o
r
m
ed
f
o
r
b
o
th
n
e
g
ati
v
e
a
n
d
p
o
s
iti
v
e
d
if
f
er
e
n
ce
v
alu
e
s
e
x
ce
p
t
th
e
d
if
f
er
e
n
ce
t
h
at
i
s
eq
u
al
to
0
o
r
1
w
h
ic
h
m
a
y
ca
u
s
e
eith
er
o
v
er
f
lo
w
o
r
u
n
d
er
f
lo
w
.
{
⌊
⌋
⌊
⌋
(
1
8
)
T
h
e
ca
teg
o
r
y
o
f
p
i
x
el
b
lo
c
k
is
s
li
g
h
tl
y
d
i
f
f
er
e
n
t
f
r
o
m
t
h
e
p
r
ev
io
u
s
o
n
e
[
1
6
]
b
ec
au
s
e
h
er
e,
t
h
e
ex
p
an
d
ab
le
is
cla
s
s
i
f
ied
i
n
to
eith
er
R
DE
ex
p
an
d
ab
le
o
r
R
D
E
n
o
n
-
ex
p
a
n
d
ab
le.
I
n
th
i
s
ca
s
e,
if
a
b
lo
ck
is
R
D
E
ex
p
an
d
ab
le,
th
e
d
i
f
f
er
en
ce
i
s
r
ed
u
ce
d
b
ef
o
r
e
th
e
e
m
b
ed
d
in
g
p
r
o
ce
s
s
;
b
u
t
i
f
it
i
s
R
DE
n
o
n
-
e
x
p
an
d
ab
le,
t
h
e
n
th
e
e
m
b
ed
d
in
g
i
s
p
er
f
o
r
m
ed
d
ir
ec
tl
y
to
th
e
o
r
ig
i
n
al
d
i
f
f
er
en
ce
s
.
T
h
e
d
r
a
w
b
ac
k
o
f
th
e
m
et
h
o
d
is
th
at
t
h
e
s
i
m
ilar
it
y
b
et
w
ee
n
th
e
h
o
s
t
i
m
ag
e
a
n
d
s
teg
o
i
m
a
g
e
is
s
ti
l
l
lo
w
.
I
n
th
e
n
e
x
t
s
ec
tio
n
,
w
e
illu
s
tr
ate
a
n
e
w
ap
p
r
o
ac
h
to
im
p
r
o
v
e
th
i
s
m
eth
o
d
.
3.
I
M
P
RO
VING
T
H
E
Q
U
AL
I
T
Y
O
F
ST
E
G
O
I
M
AG
E
I
n
t
h
is
p
ap
er
,
to
i
m
p
r
o
v
e
th
e
q
u
alit
y
o
f
s
te
g
o
i
m
a
g
e
w
e
p
r
o
p
o
s
ed
a
n
e
w
d
ata
h
id
in
g
ap
p
r
o
ac
h
b
ased
o
n
th
e
p
r
ev
io
u
s
m
et
h
o
d
s
,
esp
ec
iall
y
t
h
at
o
f
Ah
m
ad
et
a
l
[
1
7
]
.
A
n
e
w
b
ase
p
o
in
t
i
s
d
ef
i
n
ed
an
d
a
r
ed
u
ce
d
d
if
f
er
e
n
ce
f
o
r
m
u
la
i
s
p
r
o
p
o
s
ed
.
T
h
at
is
,
t
h
e
d
ata
h
id
i
n
g
a
p
p
r
o
ac
h
is
p
er
f
o
r
m
ed
i
n
t
w
o
s
u
cc
e
s
s
i
v
e
p
h
ase
s
:
e
m
b
ed
d
in
g
a
n
d
ex
tr
ac
tio
n
p
r
o
ce
s
s
es.
3
.
1
.
T
he
e
m
b
eddi
ng
pro
ce
s
s
Si
m
i
lar
to
o
th
er
r
ed
u
ce
d
d
if
f
er
en
ce
e
x
p
an
s
io
n
al
g
o
r
ith
m
s
p
r
o
p
o
s
ed
in
[
1
2
]
,
[
1
6
]
an
d
[
1
7
]
,
th
e
e
m
b
ed
d
in
g
p
r
o
ce
s
s
s
tar
ts
b
y
s
p
litt
in
g
i
m
a
g
e
i
n
to
p
ix
el
b
lo
ck
s
.
A
l
s
o
,
as
in
[
1
2
]
an
d
[
1
7
]
,
w
e
u
s
e
th
e
b
lo
ck
o
f
4
p
ix
els
an
d
d
if
f
er
en
ce
s
b
et
w
ee
n
ad
j
ac
en
t
p
ix
els
ar
e
co
m
p
u
te
d
b
ased
o
n
f
ix
ed
p
ix
el
v
al
u
e
in
ea
ch
b
lo
ck
.
I
n
th
i
s
w
o
r
k
,
t
h
e
f
i
x
ed
p
ix
el
i
s
lo
ca
te
d
at
th
e
to
p
r
ig
h
t
i
n
ea
c
h
b
lo
ck
.
I
n
a
2
2
p
ix
el
b
lo
ck
,
th
e
u
s
e
d
f
ix
ed
p
i
x
el
is
at
th
e
s
ec
o
n
d
p
o
s
itio
n
o
n
t
h
e
to
p
r
ig
h
t
co
r
n
er
.
T
h
e
p
r
o
p
o
s
ed
in
teg
e
r
tr
an
s
f
o
r
m
s
c
h
e
m
e
i
s
s
h
o
w
n
i
n
E
q
u
atio
n
(
1
9
)
.
Her
e
,
th
e
d
if
f
e
r
en
ce
s
ar
e
co
m
p
u
ted
b
y
s
u
b
tr
ac
tin
g
th
e
f
i
x
ed
p
ix
el
f
r
o
m
ea
ch
p
ix
el
in
a
b
lo
ck
.
T
h
er
ea
f
ter
,
th
e
d
if
f
er
e
n
ce
s
ar
e
s
av
ed
in
to
a
v
ec
to
r
as:
.
I
n
E
q
u
atio
n
(
1
9
)
,
th
e
s
ec
o
n
d
d
if
f
er
e
n
ce
is
eq
u
al
to
b
ec
au
s
e
th
e
p
ix
e
l i
s
f
i
x
ed
.
{
(
1
9
)
Af
ter
co
m
p
u
tin
g
t
h
e
d
if
f
er
en
ce
s
,
th
e
ch
ar
ac
ter
is
t
ic
o
f
b
lo
ck
s
is
co
n
s
id
er
ed
in
o
r
d
er
to
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ed
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ce
th
e
d
if
f
er
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n
ce
b
ef
o
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e
e
m
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ed
d
in
g
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o
th
er
w
i
s
e,
th
e
p
a
y
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ad
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ed
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ed
d
ir
ec
tly
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th
e
d
if
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er
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ce
w
it
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o
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t
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ed
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ctio
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ch
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ch
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le.
A
d
if
f
er
en
ce
is
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ed
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ce
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i
f
it
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ca
teg
o
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ized
as
ex
p
a
n
d
ab
le
w
h
ich
i
s
s
u
b
d
iv
id
ed
in
to
R
DE
ex
p
an
d
ab
le
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d
n
o
n
-
R
DE
ex
p
an
d
ab
le.
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e,
R
DE
ex
p
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n
d
ab
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is
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ed
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ce
d
f
o
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p
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s
itiv
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d
n
e
g
ati
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al
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e
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g
E
q
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(
2
0
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w
h
ile
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o
n
-
R
DE
e
x
p
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is
n
o
t
r
ed
u
ce
d
.
T
h
is
is
s
i
m
il
ar
to
ch
an
g
ea
b
le
p
ix
el
b
lo
ck
s
,
w
h
er
e
th
e
e
m
b
ed
d
in
g
is
d
o
n
e
at
th
e
o
r
ig
in
al
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
n
t J
E
lec
&
C
o
m
p
E
n
g
,
Vo
l.
8
,
No
.
4
,
A
u
g
u
s
t 2
0
1
8
:
2
4
6
8
–
2
4
7
6
2472
d
if
f
er
e
n
ce
;
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n
th
e
o
t
h
er
h
an
d
,
n
o
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-
ch
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g
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le
p
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lo
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s
a
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e
ig
n
o
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ed
d
u
e
to
o
v
e
r
f
lo
w
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d
u
n
d
er
f
lo
w
is
s
u
e
s
.
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h
e
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ed
u
ctio
n
is
d
o
n
e
as
f
o
llo
w
.
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f
t
h
e
d
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ce
b
et
w
ee
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s
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g
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ea
ter
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a
n
1
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en
th
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ir
s
t
ex
p
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io
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f
E
q
u
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(
2
0
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is
u
s
ed
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if
,
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n
t
h
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o
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d
ex
p
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ess
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n
is
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n
s
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ter
th
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d
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er
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ce
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ed
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cti
o
n
,
s
ec
r
et
d
a
ta
ar
e
em
b
ed
d
ed
.
{
(
⌊
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(
2
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≤
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T
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e
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in
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tify
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l
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w
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er
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e
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it
s
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1
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e
ass
ig
n
ed
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th
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ies:
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h
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e
x
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is
class
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ied
as
e
x
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a
b
le
R
DE
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d
n
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n
-
ex
p
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d
ab
le
R
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.
Fo
r
ex
p
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d
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le
R
DE
,
is
ass
ig
n
ed
th
e
v
al
u
e
(
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ile
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o
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ex
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n
o
n
-
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it
is
g
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e
n
th
e
v
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e
0
(
)
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e,
th
e
e
m
b
ed
d
in
g
is
p
er
f
o
r
m
ed
u
s
i
n
g
(
2
1
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f
o
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ex
p
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d
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le
p
ix
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en
,
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e
lo
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m
a
p
f
r
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m
u
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til
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e
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if
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l
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f
th
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f
ir
s
t
p
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t
o
f
E
q
u
atio
n
(
2
2
)
is
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er
if
ied
f
o
r
p
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itiv
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d
if
f
er
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s
g
r
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ter
th
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(
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.
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th
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l
y
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t
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ied
.
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is
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d
o
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e
f
o
r
n
eg
ati
v
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d
if
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er
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ce
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at
ar
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less
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h
a
n
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1
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.
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h
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m
ap
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en
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r
r
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i
n
g
s
ec
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et
d
ata.
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r
t
h
e
e
x
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le
n
o
n
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DE
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t
h
e
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m
b
ed
d
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er
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o
r
m
ed
o
n
th
e
o
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ig
i
n
al
d
if
f
er
e
n
ce
w
i
th
o
u
t
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ed
u
ctio
n
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d
t
h
e
lo
ca
tio
n
m
a
p
,
ar
e
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iv
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n
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al
u
e
1
an
d
0
r
esp
ec
tiv
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y
.
{
(
2
1
)
{
(
⌊
(
)
⌋
⌊
√
⌊
⌋
⌋
)
(
⌊
⌋
⌊
√
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⌋
⌋
)
(
2
2
)
Fo
r
ch
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g
ea
b
le
p
ix
el
b
lo
ck
s
,
t
h
e
s
ec
r
e
t
d
ata
e
m
b
ed
d
in
g
i
s
d
o
n
e
u
s
i
n
g
E
q
u
atio
n
(
2
3
)
.
T
h
e
n
,
th
e
p
ix
e
l
b
lo
ck
is
id
en
tif
ied
u
s
in
g
th
e
l
o
ca
tio
n
m
ap
b
y
co
n
s
id
er
i
n
g
th
e
o
r
ig
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al
d
if
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er
e
n
ce
as
f
o
llo
w.
I
f
is
o
d
d
,
th
en
th
e
lo
ca
tio
n
m
a
p
f
r
o
m
o
to
is
ass
i
g
n
ed
t
h
e
v
al
u
e
1
;
i
f
t
h
e
o
r
ig
i
n
al
d
i
f
f
er
e
n
ce
is
e
v
en
,
t
h
e
lo
ca
tio
n
m
ap
f
r
o
m
u
n
til
is
as
s
i
g
n
ed
th
e
v
al
u
e
0
.
Di
f
f
er
en
t
f
r
o
m
[
1
2
]
,
th
e
o
v
er
f
lo
w
o
r
u
n
d
er
f
lo
w
is
s
u
e
is
allev
iated
b
y
u
s
i
n
g
th
e
E
q
u
a
t
io
n
(
2
4
)
w
h
ic
h
m
u
s
t
b
e
ch
ec
k
ed
b
ef
o
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th
e
co
n
s
tr
u
ctio
n
o
f
n
e
w
p
i
x
el
(
s
te
g
o
p
ix
el)
u
s
i
n
g
(
2
5
)
w
h
ich
later
g
iv
es
s
te
g
o
i
m
ag
e.
Her
e,
th
e
p
i
x
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at
th
e
s
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o
n
d
p
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s
itio
n
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s
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o
t
ch
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g
ed
a
n
d
it
i
s
ad
d
ed
to
ea
ch
e
m
b
ed
d
ed
d
if
f
e
r
en
ce
.
{
⌊
⌋
⌊
⌋
⌊
⌋
(
2
3
)
Af
ter
e
m
b
ed
d
in
g
p
h
a
s
e,
t
h
e
r
e
m
ai
n
in
g
s
tep
i
s
to
co
n
s
tr
u
ct
th
e
f
u
ll
s
te
g
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i
m
ag
e
w
h
ic
h
i
s
th
e
n
s
en
t
to
g
eth
er
w
it
h
lo
ca
tio
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m
ap
to
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r
ec
eiv
er
th
r
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g
h
a
p
u
b
lic
n
et
w
o
r
k
w
h
er
e
th
e
s
ec
r
et
m
e
s
s
a
g
e
is
ex
tr
ac
ted
an
d
co
v
er
i
m
a
g
e
is
r
esto
r
ed
.
{
≤
≤
≤
≤
≤
≤
(
2
4
)
{
(
2
5
)
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
P
r
o
tectin
g
Da
ta
b
y
I
mp
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o
vin
g
Qu
a
lity o
f S
teg
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a
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d
R
ed
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ce
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(
Ma
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r
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N
ta
h
o
b
a
r
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)
2473
3
.
2
.
T
he
ex
t
ra
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n pro
ce
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th
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tr
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tio
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p
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s
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t
w
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n
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id
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ed
.
T
h
ese
ar
e
th
e
d
if
f
er
e
n
ce
b
et
w
ee
n
t
wo
p
ix
els
o
f
s
teg
o
i
m
a
g
e
an
d
lo
ca
tio
n
m
ap
.
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h
e
ex
tr
ac
tio
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p
r
o
ce
s
s
s
tar
ts
b
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id
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n
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s
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g
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m
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to
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t
h
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s
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ize
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h
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s
ize
o
f
a
b
lo
c
k
u
s
e
d
in
t
h
e
e
m
b
ed
d
in
g
p
r
o
ce
s
s
.
Af
ter
t
h
at,
t
h
e
d
if
f
er
en
ce
b
etw
ee
n
t
h
e
p
ix
el
s
t
h
at
m
ak
e
s
s
te
g
o
p
ix
el
b
lo
ck
is
c
o
m
p
u
ted
.
T
h
en
,
th
e
s
ec
r
et
m
ess
a
g
e
ex
tr
ac
tio
n
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s
p
er
f
o
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m
e
d
d
ir
ec
tly
f
r
o
m
th
e
d
if
f
er
e
n
ce
b
y
ta
k
i
n
g
th
e
least
s
ig
n
i
f
ica
n
t
b
it
(
L
SB
)
f
r
o
m
ea
c
h
d
if
f
er
en
ce
u
s
in
g
eq
u
a
tio
n
[
1
2
]
w
h
er
e
tak
es
v
a
lu
e
s
0
,
1
,
2
(
th
r
ee
b
its
to
b
e
ex
tr
ac
ted
)
.
T
h
e
o
b
tain
ed
d
if
f
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ce
f
r
o
m
s
te
g
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im
a
g
e
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t
h
e
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n
e
th
at
h
as
t
h
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r
et
m
e
s
s
a
g
e.
Du
e
to
t
h
e
d
if
f
er
en
ce
r
ed
u
c
ti
o
n
th
at
h
as
b
ee
n
p
er
f
o
r
m
ed
d
u
r
in
g
e
m
b
ed
d
in
g
p
r
o
ce
s
s
w
h
en
th
e
b
lo
ck
w
as
ex
p
an
d
ab
le
R
DE
,
t
h
is
d
i
f
f
e
r
en
ce
is
r
i
g
h
t
s
h
if
ted
to
r
etu
r
n
to
th
e
r
ed
u
ce
d
d
if
f
er
e
n
ce
.
T
h
e
o
r
ig
in
al
d
if
f
er
en
ce
s
ar
e
r
ec
o
v
er
ed
u
s
i
n
g
E
q
u
atio
n
(
2
6
)
.
{
⌊
|
|
⌋
⌊
√
⌊
⌋
⌋
i
o
⌊
|
|
⌋
⌊
√
⌊
⌋
⌋
i
o
(
2
6
)
Fo
r
n
o
n
-
R
DE
e
x
p
an
d
ab
le,
w
e
h
av
e
ad
ap
ted
th
e
f
o
r
m
u
la
p
r
o
p
o
s
ed
b
y
A
lattar
i
n
[
1
2
]
to
r
ec
o
v
er
th
e
o
r
ig
in
al
d
if
f
er
en
ce
s
u
s
i
n
g
E
q
u
atio
n
(
2
7
)
.
I
f
th
e
b
lo
ck
i
s
c
h
an
g
ea
b
le
a
n
d
d
if
f
er
en
ce
v
a
l
u
e
i
s
e
v
en
,
t
h
e
n
t
h
e
o
r
ig
in
al
d
i
f
f
er
e
n
ce
is
r
ec
o
v
er
e
d
u
s
i
n
g
t
h
e
f
ir
s
t
e
x
p
r
ess
io
n
o
f
E
q
u
atio
n
(
2
8
)
,
w
h
i
le
f
o
r
th
e
o
d
d
d
if
f
e
r
en
ce
v
alu
e
th
e
s
ec
o
n
d
p
ar
t
o
f
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q
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ted
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p
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eth
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[
1
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]
is
illu
s
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ated
in
T
ab
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1
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T
h
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s
tag
es
o
f
e
m
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h
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l b
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icted
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Fig
u
r
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1
,
i
n
th
e
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r
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1
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ar
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M
eth
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[
1
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]
M
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h
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A
h
mad
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[
1
7
]
d
y
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a
-
mi
c
{
{
⌊
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---
P
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(
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≤
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
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2474
Fig
u
r
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1
.
T
h
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p
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ed
d
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n
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tr
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4.
E
XP
E
R
I
M
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A
L
RE
SUL
T
S AN
D
D
I
SC
USS
I
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I
n
th
e
i
m
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m
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r
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ith
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its
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le
m
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ical
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m
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g
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o
f
r
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lu
tio
n
512
5
1
2
tak
en
f
r
o
m
[
1
9
]
.
I
n
ad
d
itio
n
,
to
ev
alu
ate
t
h
e
p
er
f
o
r
m
an
ce
o
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th
e
p
r
o
p
o
s
ed
m
eth
o
d
,
w
e
also
i
m
p
le
m
en
ted
th
e
m
e
th
o
d
i
n
[
1
7
]
.
Fu
r
th
er
m
o
r
e,
i
n
t
h
e
ex
p
er
i
m
e
n
t,
w
e
u
s
e
M
A
T
L
A
B
p
r
o
g
r
a
m
m
i
n
g
.
T
h
er
ea
f
ter
,
r
an
d
o
m
b
in
ar
y
b
i
ts
o
f
d
if
f
er
en
t
s
ize
s
(
5
Kb
,
1
0
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a
n
d
2
0
Kb
)
a
r
e
g
en
er
ated
u
s
in
g
a
r
an
d
o
m
f
u
n
ctio
n
.
T
h
e
v
i
s
u
a
l
q
u
ali
t
y
is
m
ea
s
u
r
ed
u
s
i
n
g
P
ea
k
Si
g
n
al
to
No
is
e
R
at
io
(
P
SNR
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an
d
Me
an
s
Sq
u
ar
e
E
r
r
o
r
(
MSE
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in
o
r
d
er
to
ev
alu
ate
h
o
w
m
u
c
h
t
h
e
o
r
ig
in
a
l
i
m
a
g
e
i
s
d
is
to
r
ted
af
ter
s
ec
r
et
m
e
s
s
a
g
e
e
m
b
ed
d
in
g
.
T
h
e
f
o
r
m
u
la
to
co
m
p
u
te
P
SNR
a
n
d
MSE
ar
e
illu
s
tr
ated
in
E
q
u
atio
n
s
(
3
0
)
an
d
(
3
1
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r
esp
ec
tiv
el
y
w
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er
e
is
th
e
n
u
m
b
er
o
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p
ix
el
s
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g
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m
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n
d
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s
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o
i
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∑
(
3
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(
3
1
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T
h
e
r
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lts
o
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h
e
e
x
p
er
i
m
e
n
t
ca
n
b
e
p
r
esen
ted
i
n
T
ab
le
2
,
T
ab
le
3
,
T
a
b
le
4
ac
co
r
d
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g
to
th
e
s
ize
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f
s
ec
r
et
m
es
s
ag
e.
T
h
at
is
,
w
e
u
s
e
5
Kb
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1
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b
,
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d
2
0
Kb
w
h
o
s
e
co
r
r
esp
o
n
d
in
g
P
S
NR
v
al
u
es
ar
e
d
ep
icted
in
T
ab
le
2
,
T
ab
le
3
an
d
T
a
b
le
4
,
r
esp
ec
tiv
el
y
.
D
u
e
to
d
i
f
f
er
en
t
p
ix
el
in
te
n
s
it
y
(
b
r
ig
h
t
n
es
s
)
,
s
m
o
o
th
n
e
s
s
a
n
d
tex
t
u
r
e,
th
e
v
is
u
al
q
u
alit
y
o
f
s
t
eg
o
i
m
a
g
e
ar
e
d
if
f
er
en
t f
o
r
t
h
e
s
a
m
e
p
a
y
lo
ad
ca
p
ac
it
y
.
I
n
s
o
m
e
ca
s
e
s
,
th
e
co
v
er
ar
e
r
elativ
el
y
s
i
m
ilar
to
t
h
e
s
t
eg
o
i
m
a
g
es,
a
s
in
d
icate
d
b
y
t
h
eir
P
SNR
v
al
u
es.
I
n
T
ab
le
2
,
w
h
er
e
th
e
s
ec
r
et
m
es
s
ag
e
i
s
s
m
aller
(
5
Kb
)
,
th
e
p
er
f
o
r
m
a
n
ce
is
b
etter
th
a
n
th
a
t
o
f
b
ig
g
er
s
ize,
as
s
h
o
w
n
i
n
T
ab
le
3
an
d
T
a
b
le
4
.
T
h
is
s
h
o
w
s
t
h
at
m
o
r
e
p
ay
lo
ad
lead
s
to
d
ec
r
ea
s
in
g
v
is
u
al
q
u
al
it
y
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
n
t J
E
lec
&
C
o
m
p
E
n
g
I
SS
N:
2
0
8
8
-
8708
P
r
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tectin
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Da
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Qu
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…
(
Ma
u
r
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ta
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o
b
a
r
i
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2475
T
ab
le
2.
P
SNR
V
alu
e
s
w
h
e
n
5
Kb
o
f
s
ec
r
et
m
es
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ag
e
is
e
m
b
ed
d
ed
I
mag
e
s
A
h
mad
e
t
a
l
.
[
1
7
]
P
r
o
p
o
se
d
me
t
h
o
d
P
S
N
R
(
d
B
)
P
S
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R
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b
d
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l
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1
5
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8
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e
g
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8
7
5
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6
1
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1
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a
d
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3
4
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2
8
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a
n
d
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7
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4
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6
4
7
6
C
h
e
st
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3
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2
.
4
5
6
4
A
v
e
r
a
g
e
3
8
.
8
9
8
1
4
3
9
.
8
6
6
4
6
T
ab
le
3.
P
SNR
V
alu
e
s
w
h
e
n
1
0
Kb
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f
s
ec
r
et
m
es
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ag
e
i
s
e
m
b
ed
d
ed
I
mag
e
s
A
h
mad
e
t
a
l
.
[
1
7
]
P
r
o
p
o
se
d
me
t
h
o
d
P
S
N
R
(
d
B
)
P
S
N
R
(
d
B
)
A
b
d
o
mi
n
a
l
3
7
.
6
8
0
5
3
8
.
1
7
4
5
L
e
g
3
8
.
0
5
3
7
3
8
.
9
3
1
3
H
e
a
d
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1
.
9
0
5
0
3
2
.
7
2
7
2
H
a
n
d
3
7
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5
6
0
9
3
8
.
0
3
3
6
C
h
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st
3
8
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0
6
3
4
3
9
.
1
5
3
2
A
v
e
r
a
g
e
3
6
.
6
5
2
7
3
7
.
4
0
3
9
T
ab
le
4.
P
SNR
V
alu
e
s
w
h
e
n
20
Kb
o
f
s
ec
r
et
m
es
s
ag
e
i
s
e
m
b
ed
d
ed
I
mag
e
s
A
h
mad
e
t
a
l
.
[
1
7
]
P
r
o
p
o
se
d
me
t
h
o
d
P
S
N
R
(
d
B
)
P
S
N
R
(
d
B
)
A
b
d
o
mi
n
a
l
3
7
.
6
7
8
1
3
8
.
1
7
1
8
L
e
g
3
8
.
0
0
8
8
3
8
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8
3
2
3
H
e
a
d
3
1
.
9
0
4
8
3
2
.
7
2
6
3
H
a
n
d
3
7
.
5
5
6
3
3
8
.
0
3
1
0
C
h
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st
3
8
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0
6
1
7
3
9
.
0
5
2
4
A
v
e
r
a
g
e
3
6
.
6
4
1
9
3
7
.
3
6
2
7
Fig
u
r
e
2
.
P
SNR
(
av
er
ag
e)
co
m
p
ar
i
s
o
n
b
et
w
ee
n
th
e
p
r
o
p
o
s
ed
an
d
[
1
7
]
I
n
b
o
th
p
r
o
p
o
s
ed
an
d
p
r
ev
io
u
s
m
et
h
o
d
in
[
1
7
]
,
th
e
v
is
u
al
q
u
alit
y
i
s
b
etter
f
o
r
c
h
est
i
m
a
g
e
th
an
o
th
er
m
ed
ical
i
m
ag
e
s
,
w
h
ile
t
h
e
lo
wer
p
er
f
o
r
m
a
n
ce
is
o
b
tain
ed
f
o
r
th
e
h
ea
d
i
m
a
g
e.
T
h
e
r
ea
s
o
n
o
f
t
h
is
p
h
en
o
m
en
o
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ca
n
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e
d
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e
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m
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g
e
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h
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h
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d
th
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lo
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t
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f
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Me
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s
h
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es
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et
w
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n
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ite
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n
d
b
lack
.
T
h
er
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o
r
e,
in
ca
s
e
m
a
n
y
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s
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e
w
h
ite
(
h
ea
d
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o
r
b
lack
(
ch
est),
th
is
ch
ar
a
cter
is
tic
af
f
ec
ts
t
h
e
co
m
p
u
ted
d
if
f
er
en
ce
,
w
h
ic
h
a
l
s
o
in
f
lu
e
n
ce
s
t
h
e
v
is
u
al
q
u
ali
t
y
o
f
s
te
g
o
i
m
a
g
e
a
f
ter
th
e
e
m
b
ed
d
in
g
p
r
o
ce
s
s
.
T
h
e
p
er
f
o
r
m
ac
e
o
f
t
w
o
al
g
o
r
ith
m
s
f
o
r
all
f
i
v
e
m
ed
ical
i
m
a
g
es
i
s
ev
al
u
ated
b
ased
o
n
th
e
av
er
ag
e
o
f
P
SNR
f
o
r
ea
ch
s
ec
r
et
s
ize,
wh
o
s
e
r
es
u
lt
s
ar
e
p
r
ese
n
ted
i
n
Fig
u
r
e
2
.
Her
e,
t
h
e
r
e
s
u
lt
s
p
r
o
v
e
t
h
at
t
h
e
p
r
o
p
o
s
ed
m
et
h
o
d
p
er
f
o
r
m
s
b
etter
f
o
r
e
ac
h
s
ize
o
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RE
F
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NC
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S
[1
]
A
.
K.
S
a
h
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d
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.
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in
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teg
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s,"
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d
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trica
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3
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Hu
a
n
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.
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Ch
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T
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k
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Bo
risa
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a
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-
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Ju
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,
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h
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it
y
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d
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.
Y.
S
h
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a
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X.
Z
h
o
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,
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In
telli
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W
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Hig
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tern
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o
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J.
T
ian
,
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it
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2
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Hu
a
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d
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Da
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2
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A
.
M
.
A
lattar,
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