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n
g
er
p
r
in
ti
n
g
.
I
n
f
i
n
g
er
p
r
in
t
in
g
u
n
iq
u
e
m
ar
k
s
ar
e
e
m
b
ed
d
ed
in
d
is
tin
ct
co
p
ies
o
f
th
e
ca
r
r
ier
o
b
j
ec
t
th
at
ar
e
s
u
p
p
lied
to
d
if
f
er
en
t
c
u
s
to
m
er
s
[
6
]
.
T
h
e
o
u
tp
u
t
i
m
a
g
e
is
ca
lled
s
te
g
o
-
i
m
a
g
e
th
at
i
s
s
i
m
ilar
to
th
e
co
v
er
m
ed
ia.
T
h
is
s
te
g
o
-
i
m
a
g
e
is
th
e
n
s
en
t
to
t
h
e
r
ec
eiv
er
w
h
er
e
t
h
e
r
ec
eiv
er
r
etr
iev
es
th
e
h
id
d
en
m
e
s
s
a
g
e
b
y
i
m
p
le
m
e
n
ti
n
g
a
d
e
-
s
teg
a
n
o
g
r
ap
h
y
p
r
o
ce
s
s
.
A
s
te
g
o
-
k
e
y
is
u
s
ed
f
o
r
an
e
m
b
ed
d
in
g
o
r
en
co
d
in
g
p
r
o
ce
s
s
to
li
m
it
u
n
r
av
e
lin
g
o
r
ex
tr
ac
tio
n
o
f
t
h
e
e
m
b
ed
d
ed
d
ata
in
co
v
er
m
ed
ia
[
5
]
.
T
h
e
s
teg
o
-
k
e
y
d
ep
en
d
in
g
o
n
r
an
d
o
m
g
en
er
atio
n
u
s
e
s
a
s
p
ec
if
ic
k
er
n
el
in
o
r
d
er
to
s
en
d
it
to
th
e
r
ec
ip
ien
t
to
g
en
er
ate
t
h
e
s
a
m
e
k
e
y
i
n
o
r
d
er
to
r
etr
iev
e
th
e
h
i
d
d
en
d
ata
an
d
d
ata
is
em
b
ed
d
ed
in
a
co
v
er
i
m
ag
e
u
s
i
n
g
L
SB
m
et
h
o
d
.
L
ea
s
t
-
Si
g
n
i
f
ica
n
t
-
B
it
(
L
SB
)
is
o
n
e
o
f
th
e
p
o
p
u
lar
an
d
f
r
eq
u
en
tl
y
u
s
ed
s
te
g
a
n
o
g
r
ap
h
y
tech
n
iq
u
es to
co
n
ce
al
a
m
y
s
ter
y
m
e
s
s
a
g
e
in
a
d
i
g
ital
m
ed
iu
m
[
7
]
.
T
h
e
m
eth
o
d
r
ec
o
m
m
e
n
d
ed
in
th
is
p
ap
er
is
u
s
ed
a
r
a
n
d
o
m
k
e
y
g
en
er
ato
r
m
eth
o
d
f
o
r
i
m
p
r
o
v
e
m
e
n
t
i
n
r
o
b
u
s
t
an
d
s
ec
u
r
it
y
o
f
s
te
g
a
n
o
g
r
ap
h
y
.
T
h
e
r
an
d
o
m
n
u
m
b
er
g
en
er
ato
r
lo
ca
tes
th
e
h
id
in
g
p
o
s
itio
n
s
i
n
th
e
co
v
e
r
i
m
a
g
e
in
ea
ch
r
o
w
s
ep
ar
atel
y
a
n
d
ea
ch
r
o
w
w
ill
h
id
e
th
e
s
a
m
e
n
u
m
b
er
o
f
b
it
s
o
f
s
e
cr
et
tex
t.
T
h
at’
s
b
y
d
iv
id
in
g
t
h
e
s
ec
r
et
te
x
t
o
n
all
th
e
r
o
w
s
o
f
t
h
e
co
v
er
i
m
ag
e.
s
p
ec
if
ic
m
et
h
o
d
f
o
r
h
id
in
g
b
it
s
in
ea
c
h
p
ix
el
w
i
ll
b
e
u
s
ed
.
2.
RE
L
AT
E
D
WO
RK
S
I
n
a
s
teg
a
n
o
g
r
ap
h
y
f
ield
,
th
e
r
e
ar
e
m
a
n
y
r
esear
c
h
er
s
u
s
in
g
a
r
an
d
o
m
n
u
m
b
er
g
en
er
ati
o
n
m
et
h
o
d
co
m
b
i
n
ed
w
it
h
a
n
o
th
er
tec
h
n
i
q
u
e
f
o
r
h
id
in
g
i
n
f
o
r
m
atio
n
i
n
i
m
a
g
e.
Ob
aid
a
M.
an
d
Aw
ad
A
.
i
n
tr
o
d
u
ce
d
th
at
th
e
s
ec
r
et
te
x
t
b
it
s
ar
e
i
n
s
er
te
d
in
to
t
h
e
co
v
er
i
m
ag
e
p
ix
el
s
r
an
d
o
m
l
y
.
W
h
er
ea
s
,
i
n
s
er
ti
n
g
o
f
s
ec
r
et
tex
t
b
its
in
to
t
h
e
co
v
er
i
m
a
g
e
w
il
l
b
e
i
n
a
n
y
b
it
o
f
t
h
e
p
i
x
el
r
an
d
o
m
l
y
b
y
co
m
p
ar
in
g
t
h
e
m
es
s
ag
e
b
it
w
it
h
t
h
e
p
ix
el
b
it
th
at
c
h
o
s
e
n
r
an
d
o
m
l
y
f
r
o
m
t
h
e
s
ec
o
n
d
to
t
h
e
la
s
t
b
it.
T
h
e
least
s
i
g
n
i
f
ica
n
t
b
it
o
f
th
e
p
i
x
el
w
i
ll
b
e
1
i
f
th
e
co
m
p
ar
is
o
n
r
es
u
lt
i
s
m
atch
ed
.
An
d
th
e
lea
s
t
s
ig
n
i
f
ica
n
t
b
it
o
f
th
e
p
i
x
el
w
i
ll
b
e
0
if
t
h
e
co
m
p
ar
is
o
n
r
es
u
lt
is
n
o
t [
3
]
.
B
ab
ita
el
al
u
s
ed
a
r
a
n
d
o
m
k
e
y
g
en
er
ati
n
g
m
et
h
o
d
to
en
cr
y
p
t
th
e
s
ec
r
et
m
es
s
ag
e
u
s
i
n
g
X
OR
m
et
h
o
d
th
en
e
m
b
ed
d
in
g
th
e
cip
h
er
m
ess
a
g
e
i
n
to
an
i
m
ag
e
o
f
R
G
B
f
o
r
m
at
in
a
s
p
ec
ial
ar
r
an
g
e
m
en
t.
T
h
e
r
es
u
lted
R
GB
i
m
a
g
e
co
n
v
er
ted
in
to
th
e
b
i
tm
ap
f
i
le
f
o
r
m
at
[
9
]
.
B
alv
in
d
er
el
al.
en
cr
y
p
ted
th
e
s
ec
r
et
tex
t
u
s
i
n
g
XOR
en
cr
y
p
tio
n
m
eth
o
d
u
s
i
n
g
8
-
b
i
t
r
an
d
o
m
k
e
y
.
T
h
en
,
ap
p
lied
XOR
o
p
er
atio
n
b
et
w
ee
n
o
n
e
b
it
o
f
8
-
b
it
r
a
n
d
o
m
k
e
y
a
n
d
2
n
d
L
SB
o
f
co
v
er
i
m
ag
e
p
i
x
el.
I
f
t
h
e
XOR
r
es
u
l
t
o
f
ab
o
v
e
o
p
er
atio
n
is
1
th
en
h
id
e
o
n
e
b
it
o
f
th
e
s
ec
r
et
k
e
y
i
n
to
L
SB
o
f
s
a
m
e
p
ix
el
o
f
co
v
er
i
m
a
g
e.
Oth
er
w
i
s
e,
th
er
e
is
n
o
h
id
in
g
i
n
an
y
b
it
in
th
at
p
ix
e
l.
T
h
e
E
x
t
r
a
c
t
e
d
se
c
r
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t
m
e
ssa
g
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ssa
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C
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r
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a
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e
S
t
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g
a
n
o
g
r
a
p
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schem
a
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r
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o
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r
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c
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t
Ke
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o
m
m
u
n
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c
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t
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o
n
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h
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[
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No
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h
id
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m
eth
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h
e
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cr
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p
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ib
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ted
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m
ag
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p
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x
els
u
s
in
g
p
er
m
u
tatio
n
tec
h
n
iq
u
e.
T
h
en
h
id
e
t
h
e
b
its
o
f
t
h
e
e
n
cr
y
p
ted
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es
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ag
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in
co
v
er
i
m
a
g
e
i
n
t
h
e
r
an
d
o
m
l
y
s
elec
ted
p
ix
els
[
1
1
]
.
A
s
h
w
in
i
an
d
k
o
m
al
p
r
o
v
id
ed
s
eq
u
en
tial
en
co
d
in
g
a
n
d
r
an
d
o
m
en
co
d
in
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w
a
y
s
f
o
r
e
m
b
ed
d
in
g
t
h
e
s
ec
r
et
d
ata
i
n
s
id
e
co
v
er
i
m
ag
e.
Seq
u
e
n
tial
e
n
co
d
in
g
u
s
ed
o
n
e
k
e
y
en
ter
ed
b
y
u
s
er
a
n
d
s
e
q
u
en
tial
l
y
s
elec
te
d
th
e
p
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x
el
f
o
r
e
m
b
ed
d
in
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cip
h
er
tex
t
o
b
tain
ed
b
y
XO
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i
n
g
t
h
e
s
ec
r
et
m
es
s
ag
e
w
it
h
k
e
y
p
r
o
v
id
ed
b
y
u
s
er
.
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n
r
an
d
o
m
en
co
d
i
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g
t
w
o
k
e
y
s
ar
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h
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u
s
er
,
o
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e
i
s
to
lo
ck
th
e
f
u
n
ctio
n
o
n
r
ec
eiv
e
r
s
id
e
an
d
o
th
er
f
o
r
to
ca
r
r
y
o
u
t
e
n
cr
y
p
tio
n
.
I
n
th
i
s
ca
s
e
p
i
x
els
ar
e
s
elec
ted
r
a
n
d
o
m
l
y
f
o
r
e
m
b
ed
d
in
g
s
ec
r
et
d
a
ta
i.e
eit
h
er
tex
t
o
r
i
m
a
g
e
u
s
in
g
r
an
d
o
m
n
u
m
b
er
g
en
er
ato
r
w
h
ich
a
u
to
m
atica
ll
y
i
m
p
le
m
e
n
t
s
li
n
k
li
s
t c
o
n
ce
p
t
[
1
]
.
T
h
e
tech
n
iq
u
e
t
h
at
u
s
ed
b
y
R
u
p
ali
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.
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n
d
Vais
h
ali
S.
in
c
lu
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ed
th
r
ee
m
ai
n
s
tep
s
.
T
h
at
's
b
y
f
o
u
n
d
co
m
p
le
m
e
n
ti
n
g
o
f
th
e
s
ec
r
et
tex
t.
T
h
en
,
h
id
i
n
g
t
h
e
co
m
p
le
m
en
ted
tex
t
i
n
co
v
er
i
m
ag
e
p
ix
els
u
s
i
n
g
p
s
eu
d
o
r
an
d
o
m
n
u
m
b
er
g
e
n
er
ato
r
,
f
i
n
all
y
,
h
id
e
th
e
b
its
o
f
co
m
p
l
e
m
en
ted
tex
t
i
n
ea
c
h
p
ix
e
l
u
s
in
g
t
h
e
i
n
v
er
ted
b
i
t
L
SB
m
eth
o
d
[
5
]
.
M
ee
n
ak
s
h
i
S.
an
d
et
a
l
in
tr
o
d
u
ce
d
an
R
GB
i
m
ag
e
e
m
b
ed
d
in
g
m
e
th
o
d
b
ased
o
n
s
ix
tee
n
-
p
ix
el
d
i
f
f
er
e
n
ci
n
g
w
it
h
n
-
b
it
L
ea
s
t
Si
g
n
i
f
ica
n
t
B
it
(
L
SB
)
s
u
b
s
tit
u
tio
n
.
I
n
t
h
eir
m
et
h
o
d
,
th
e
i
m
a
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ased
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it
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b
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[
1
3
]
.
I
n
th
is
p
ap
er
,
a
n
e
w
m
et
h
o
d
is
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r
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a
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as
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.
3.
T
H
E
P
RO
P
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SE
D
M
E
T
H
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D
T
h
is
p
ap
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a
n
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ed
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tex
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g
r
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m
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d
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tech
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iq
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w
it
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k
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d
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p
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as
h
f
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h
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r
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w
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b
its
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at
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h
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en
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d
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it
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g
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h
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eq
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th
e
m
eth
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Fig
u
r
e
2
.
P
r
o
p
o
s
ed
m
eth
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d
p
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ce
s
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tag
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T
h
e
p
r
o
p
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s
ed
m
eth
o
d
s
tep
s
d
e
p
icted
in
th
e
f
o
llo
w
in
g
:
Step
1
(
C
o
n
v
er
t
th
e
s
ec
r
et
te
x
t
to
t
h
e
o
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e
b
i
n
ar
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ea
m
)
:
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h
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tex
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is
a
s
tr
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co
n
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i
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ti
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f
letter
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,
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p
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p
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ial
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ter
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ac
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c
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it
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h
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m
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ter
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m
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f
th
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ec
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tex
t
is
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T
o
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1
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2
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T
h
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as in
E
q
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1
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.
n
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l =
n
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tex
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/ (
n
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w
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1)
(
1
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C
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Evaluation Warning : The document was created with Spire.PDF for Python.
I
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I
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4
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201
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3
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o
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e
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y
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e
f
o
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3
-
1
C
r
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te
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s
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d
to
g
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ate
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ar
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4
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it
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m
l
y
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m
et
h
o
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w
il
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b
e
in
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ev
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s
e
m
a
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f
o
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th
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c
u
r
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en
t
r
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w
.
Fo
r
ex
a
m
p
le,
i
f
th
e
n
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m
b
er
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f
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lu
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n
s
allo
ca
ted
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o
r
ea
ch
r
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w
is
1
0
co
lu
m
n
s
,
t
h
en
th
er
e
ar
e
1
0
b
its
o
f
s
ec
r
et
tex
t
t
h
at
w
o
u
ld
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e
h
id
d
en
in
ea
c
h
r
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w
.
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er
e,
th
e
te
n
th
b
it
w
il
l
h
id
e
in
t
h
e
f
ir
s
t
co
lu
m
n
a
n
d
th
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n
i
n
t
h
b
it
w
ill
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id
e
in
t
h
e
s
ec
o
n
d
co
lu
m
n
a
n
d
s
o
o
n
.
Step
5
E
ac
h
p
ix
el
h
av
e
8
b
its
.
T
o
h
id
e
o
n
e
b
it
in
o
n
e
p
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w
e
w
ill
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s
e
t
h
e
u
p
d
ated
L
S
B
m
et
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o
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th
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s
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c
lu
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g
a
s
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m
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h
as
h
f
u
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ctio
n
.
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h
is
m
eth
o
d
in
cl
u
d
e
s
h
id
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a
b
it
in
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ig
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f
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ce
b
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in
th
e
cu
r
r
en
t
p
ix
el.
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h
e
ch
o
s
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a
m
o
n
g
th
e
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r
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t r
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m
s
elec
ted
co
lu
m
n
.
As d
ep
icted
in
E
q
u
atio
n
(
2
)
.
x
=
len
_
p
x
l
–
(
co
l_
in
d
x
m
o
d
3
)
(
2
)
W
h
er
e,
x
r
ep
r
esen
t
th
e
lo
ca
tio
n
o
f
h
id
in
g
t
h
e
b
it
in
t
h
e
p
ix
el
,
len
_
p
x
l
d
ep
icted
to
th
e
len
g
t
h
o
f
p
ix
el
th
at
w
i
ll
b
e
8
b
its
,
co
l_
in
d
x
d
en
o
ted
to
th
e
in
d
e
x
o
f
t
h
e
c
u
r
r
en
t
r
an
d
o
m
s
elec
ted
co
lu
m
n
.
I
f
t
h
e
r
e
s
u
lted
x
is
eq
u
al
to
0
,
1
o
r
2
,
th
en
t
h
e
b
it
w
il
l
h
i
d
e
in
t
h
e
ei
g
h
th
,
s
ev
e
n
t
h
o
r
s
ix
t
h
b
it
o
f
t
h
e
p
ix
el,
r
e
s
p
ec
tiv
el
y
.
T
h
e
f
o
llo
w
i
n
g
ex
a
m
p
le
il
lu
s
tr
ates t
h
e
ab
o
v
e
s
tep
s
o
f
o
u
r
m
et
h
o
d
in
d
etails.
L
et
's
th
e
s
ec
r
et
tex
t
h
a
v
e
7
0
0
ch
ar
ac
ter
s
.
W
h
en
co
n
v
er
ti
n
g
i
t
to
b
in
ar
y
,
ea
ch
c
h
ar
ac
ter
w
il
l
co
n
v
er
t
to
7
b
its
.
T
h
at
m
ea
n
s
,
t
h
e
le
n
g
th
o
f
s
ec
r
et
te
x
t
i
n
b
i
n
ar
y
w
i
ll
b
e
7
*
7
0
0
=4
9
0
0
b
its
.
Fo
r
th
e
co
v
er
i
m
a
g
e
w
it
h
s
ize
5
1
2
*
5
1
2
p
ix
el,
ea
ch
r
o
w
w
il
l
co
n
tai
n
n
u
m
b
er
o
f
b
its
o
f
s
ec
r
et
tex
t
co
m
p
u
ted
as
f
o
llo
w
i
n
g
:
n
o
_
co
l=f
lo
o
r
(
4
9
0
0
/(
5
1
2
-
1
)
)
+1
=
1
0
b
its
o
f
t
h
e
s
ec
r
et
te
x
t
h
id
d
en
in
ea
c
h
r
o
w
o
f
t
h
e
co
v
er
i
m
ag
e.
W
h
e
r
e
f
lo
o
r
(
A
)
r
o
u
n
d
s
th
e
ele
m
en
t
s
o
f
A
to
th
e
n
ea
r
e
s
t in
te
g
er
s
le
s
s
t
h
an
o
r
eq
u
al
t
o
A
.
No
w
,
w
e
u
s
e
t
h
e
r
an
d
o
m
f
u
n
c
tio
n
to
g
en
er
ate
1
0
co
lu
m
n
s
'
i
n
d
ex
es
in
r
an
g
e
(
1
-
5
1
2
)
.
First
,
g
en
er
ate
th
e
s
tar
t
r
an
d
o
m
s
ee
d
u
s
in
g
s
h
u
f
f
le
f
u
n
ctio
n
f
o
r
ex
a
m
p
le:
s
e
ed
=
1
8
9
7
0
3
9
2
4
6
.
T
h
is
s
ee
d
w
i
ll
b
e
co
n
s
id
er
ed
a
s
s
ec
r
et
k
e
y
t
h
at
'
s
s
e
n
t
to
r
ec
eiv
er
b
y
h
id
i
n
g
it
i
n
th
e
las
t
r
o
w
o
f
co
v
er
i
m
ag
e
u
s
i
n
g
L
SB
m
e
th
o
d
.
T
h
e
r
ec
ei
v
er
w
il
l
u
s
e
t
h
is
s
ee
d
to
g
en
er
ate
t
h
e
s
a
m
e
s
eq
u
en
ce
s
o
f
r
an
d
o
m
n
u
m
b
er
s
to
g
e
t
th
e
s
ec
r
et
tex
t.
T
h
en
,
g
en
er
ate
1
0
co
lu
m
n
in
d
e
x
es
in
r
an
g
e
(
1
-
5
1
2
)
f
o
r
ea
ch
r
o
w
i
n
co
v
er
i
m
ag
e
ex
ce
p
t
th
e
last
o
n
e
u
s
i
n
g
s
tep
(
3
-
2
)
.
W
h
en
n
=5
1
2
,
n
o
_
co
l=1
0
,
th
e
f
ir
s
t 1
0
co
lu
m
n
s
i
n
d
ex
e
s
g
e
n
er
ated
in
o
u
r
ex
a
m
p
le
w
il
l b
e:
1
6
5
3
6
3
2
3
3
3
3
5
1
0
5
1
3
8
1
9
9
4
2
0
6
3
4
1
8
I
f
t
h
e
f
ir
s
t
1
0
b
its
i
n
s
ec
r
et
te
x
t
ar
e:
1
0
1
0
1
0
0
1
1
0
,
th
en
t
h
e
h
id
in
g
o
f
t
h
ese
b
its
in
th
e
f
ir
s
t
r
o
w
a
n
d
r
a
n
d
o
m
s
elec
ted
co
lu
m
n
s
w
ill b
e
in
r
e
v
er
s
e
m
a
n
n
er
as:
T
h
at
m
ea
n
s
th
e
1
0
th
s
ec
r
et
b
it
w
ill
h
id
e
i
n
t
h
e
1
6
6
th
co
lu
m
n
a
n
d
t
h
e
9
t
h
b
it
w
ill
h
id
e
in
3
6
3
th
co
l
u
m
n
,
an
d
s
o
o
n
.
No
w
,
w
e
d
eter
m
in
ed
th
e
p
ix
el(
r
o
w
,
co
l
u
m
n
)
f
r
o
m
co
v
er
i
m
ag
e
f
o
r
ea
ch
b
it
i
n
s
ec
r
et
tex
t.
T
o
h
id
e
th
e
1
0
th
b
it (
0
)
in
t
h
e
p
i
x
el(
1
,
1
6
6
)
,
w
e
u
s
e
m
o
d
o
p
er
atio
n
as a
s
i
m
p
le
h
a
s
h
f
u
n
ct
io
n
as
in
s
tep
(
3
-
4
)
to
f
in
d
t
h
e
in
d
ex
o
f
h
id
i
n
g
t
h
e
s
ec
r
et
b
it i
n
th
e
p
i
x
el
b
its
.
I
f
t
h
at
i
n
d
ex
(
x
)
is
co
m
p
u
ted
as:
x
=
len
_
p
x
l
-
(
co
l_
in
d
x
m
o
d
3
)
x
=8
-
(
1
6
6
m
o
d
3
)
=
7
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:
2088
-
8708
T
ex
t in
I
ma
g
e
Hid
in
g
u
s
in
g
D
ev
elo
p
ed
LS
B
a
n
d
R
a
n
d
o
m
Meth
o
d
(
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la
f A
li A
b
b
o
o
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2095
T
h
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e
1
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th
s
ec
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et
b
it
(
0
)
w
il
l
h
id
e
i
n
th
e
7
t
h
b
it
o
f
t
h
e
p
ix
el
(
1
,
1
6
6
)
.
I
f
th
e
g
r
a
y
co
lo
r
o
f
th
e
p
ix
el
(
1
,
1
6
6
)
=
0
1
0
1
0
0
1
1
,
th
e
n
t
h
e
7
t
h
b
it
o
f
th
e
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ix
e
l
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l
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e
r
ep
lace
d
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y
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h
e
1
0
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s
ec
r
et
b
it
(
0
)
o
f
t
h
e
s
ec
r
et
tex
t.
T
h
e
r
esu
lt o
f
th
e
p
i
x
el
(
1
,
1
6
6
)
=
0
1
0
1
0
0
0
1
.
W
h
en
t
h
e
s
teg
o
i
m
a
g
e
ar
r
iv
es
to
th
e
r
ec
eiv
er
,
t
h
e
r
ec
eiv
er
w
il
l
b
e
ex
tr
ac
ted
t
h
e
s
ec
r
et
tex
t
b
y
ap
p
ly
i
n
g
th
e
s
a
m
e
h
id
i
n
g
s
tep
s
.
I
n
th
e
f
o
llo
w
in
g
,
t
h
e
s
tep
s
o
f
ex
tr
ac
tio
n
th
e
s
ec
r
et
tex
t
:
Step
1
:
E
x
tr
ac
tio
n
o
f
th
e
s
ee
d
r
an
d
o
m
g
en
er
at
io
n
an
d
l
en
g
t
h
o
f
th
e
s
ec
r
et
tex
t.
First
t
h
e
r
ec
eiv
er
m
u
s
t
ex
tr
ac
t
th
e
s
ee
d
o
f
g
en
er
ate
t
h
e
r
an
d
o
m
s
eq
u
e
n
ce
an
d
al
s
o
ex
tr
ac
t
th
e
len
g
t
h
o
f
s
ec
r
et
tex
t
t
h
at
h
id
e
in
t
h
e
las
t
r
o
w
o
f
th
e
s
te
g
o
i
m
ag
e
u
s
i
n
g
L
SB
tr
ad
itio
n
al
m
et
h
o
d
.
Step
2
:
Fin
d
th
e
n
u
m
b
er
o
f
co
lu
m
n
s
th
at
u
s
ed
to
h
id
e
t
h
e
s
ec
r
et
tex
t
b
its
u
s
i
n
g
E
q
u
a
tio
n
(
1
)
.
Step
3
:
Gen
er
ate
a
r
an
d
o
m
l
o
ca
tio
n
s
f
o
r
th
e
n
u
m
b
er
o
f
c
o
lu
m
n
s
i
n
ea
ch
r
o
w
.
T
h
at’
s
d
o
n
e
u
s
i
n
g
a
p
s
eu
d
o
r
an
d
o
m
g
e
n
er
atio
n
m
et
h
o
d
s
tar
ted
u
s
in
g
t
h
e
s
ee
d
th
at
e
x
tr
ac
t
ed
in
s
tep
1
.
Step
4
:
E
x
tr
ac
tio
n
o
f
s
ec
r
et
te
x
t b
it
s
.
T
o
ex
tr
ac
t t
h
e
s
ec
r
et
te
x
t b
it
s
,
w
e
u
s
e
t
h
e
s
a
m
e
m
et
h
o
d
to
h
id
e
t
h
ese
b
its
in
i
m
a
g
e.
W
h
er
e,
th
e
f
ir
s
t
b
it
w
ill
b
e
ex
tr
ac
ted
f
r
o
m
t
h
e
last
r
an
d
o
m
co
lu
m
n
a
n
d
th
e
s
ec
o
n
d
b
it
w
ill
b
e
ex
tr
ac
ted
f
r
o
m
t
h
e
s
ec
o
n
d
last
r
an
d
o
m
co
lu
m
n
a
n
d
s
o
o
n
.
T
o
ex
tr
ac
t
t
h
e
b
it
f
r
o
m
t
h
e
p
i
x
e
l,
w
e
u
s
e
t
h
e
m
o
d
o
p
er
atio
n
u
s
in
g
E
q
u
at
io
n
(
2
)
.
Step
5
:
C
o
n
v
er
t
t
h
e
s
ec
r
et
te
x
t
b
its
to
ch
ar
ac
ter
s
.
T
h
e
ex
tr
ac
ted
s
ec
r
et
tex
t
is
o
n
e
s
eq
u
e
n
ce
o
f
b
in
ar
y
b
its
.
T
o
co
v
er
t th
e
s
ec
r
et
tex
t
f
r
o
m
b
in
ar
y
to
ch
ar
ac
ter
s
,
ea
ch
s
ev
e
n
b
its
w
ill co
n
v
er
t to
o
n
e
ch
ar
ac
ter
.
4.
RE
SU
L
T
S
T
h
e
p
r
o
p
o
s
ed
m
et
h
o
d
u
s
ed
an
ef
f
icien
t
an
d
s
ec
u
r
e
s
c
h
e
m
a
t
o
h
id
e
s
ec
r
et
tex
t
in
i
m
a
g
e.
T
h
is
s
ec
tio
n
illu
s
tr
ates
t
h
e
r
es
u
lt
s
o
f
ap
p
l
y
in
g
th
e
p
r
o
p
o
s
ed
m
et
h
o
d
to
h
id
e
d
if
f
er
e
n
t
s
ec
r
et
te
x
t
s
ize
o
n
d
if
f
er
e
n
t
i
m
ag
e
s
an
d
m
ea
s
u
r
e
th
e
ac
cu
r
ac
y
o
f
th
e
r
es
u
l
ted
i
m
a
g
es
u
s
in
g
P
S
NR
a
n
d
SS
I
M
m
e
a
s
u
r
e
m
e
n
ts
th
at
’
s
d
escr
ib
es
i
n
E
q
u
atio
n
(
3
)
an
d
E
q
u
atio
n
(
4
)
,
r
esp
ec
tiv
el
y
.
[
∑
∑
]
(
3
)
W
h
er
e
in
d
icate
d
to
th
e
s
tr
eg
o
im
a
g
e
p
ix
els
an
d
in
d
icate
d
to
th
e
co
v
er
im
ag
e
v
a
lu
e
s
.
M
an
d
N
is
th
e
i
m
a
g
e
s
ize.
(
)
(
)
(
4
)
W
h
er
e
µ
d
en
o
ted
t
o
th
e
m
ea
n
o
f
th
e
(
m
,
n
)
w
i
n
d
o
w
.
ar
e
in
d
icate
d
to
th
e
s
tan
d
ar
d
d
e
v
iatio
n
o
f
(
m
,
n
)
w
i
n
d
o
w
.
Fi
g
u
r
e
3
,
F
ig
u
r
e
4
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I
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N:
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RE
F
E
R
E
N
C
E
S
[1
]
A
sh
w
in
i
B.
a
n
d
Ko
m
a
l
B.
,
“
Hy
b
rid
A
p
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a
g
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in
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v
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g
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5
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o
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5
,
2
0
1
6
.
[2
]
Ya
n
g
Re
n
-
e
r
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n
d
e
t
a
l
,
“
I
m
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g
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teg
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m
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d
w
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DES
En
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p
ti
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re
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in
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S
ixth
In
ter
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t
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l
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fer
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e
o
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h
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h
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tro
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t
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ma
ti
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n
,
p
p
.
3
2
3
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2
6
,
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0
1
4
.
[3
]
Ob
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m
m
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d
Aw
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d
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l
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Ha
z
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i
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h
,
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in
g
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t
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in
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m
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g
e
s
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g
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n
d
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m
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h
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iq
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ter
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m
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e
s
, v
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l.
9
,
2
0
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2
.
[4
]
A
rtz,
D.,
“
Dig
it
a
l
S
teg
a
n
o
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ra
p
h
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:
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ta w
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IEE
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t
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m
p
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g
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o
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.
[5
]
Ru
p
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Bh
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r
d
w
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In
v
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6
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A
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s In
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in
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&
Co
mm
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[6
]
M
.
A
.
W
a
k
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a
n
d
S
.
A
.
W
a
k
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re
,
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A
Dig
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m
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g
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ra
p
h
y
”
,
In
ter
n
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ti
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o
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o
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mp
u
ter
S
c
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c
e
T
re
n
d
s a
n
d
T
e
c
h
n
o
lo
g
y
(
IJ
CS
T
)
,
v
o
l.
5
,
n
o
.
2
,
2
0
1
7
.
[7
]
Eb
ra
h
im
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lr
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sh
e
d
a
n
d
S
u
o
o
d
S
u
o
o
d
A
lro
o
m
i,
“
Hu
n
g
a
rian
-
P
u
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z
led
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e
x
t
w
it
h
D
y
n
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m
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a
d
ra
ti
c
Em
b
e
d
d
in
g
S
teg
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n
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ra
p
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y
”
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v
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l.
7,
n
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2
,
2
0
1
7
.
[8
]
Re
ih
a
n
e
S
a
n
iei
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n
d
Ka
rim
F
a
e
z
,
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c
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f
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m
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ti
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p
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a
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ter
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.
[9
]
Ba
b
it
a
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,
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0
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lv
in
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in
g
h
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