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Fi
g
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r
e
1.
T
y
p
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f
Steg
a
n
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ap
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[
3
]
Fig
u
r
e
1
.
B
lo
ck
Diag
r
a
m
o
f
St
eg
an
o
g
r
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1
.
1
.
L
ing
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ic
Ste
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no
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h
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lin
g
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o
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m
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I
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ca
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r
th
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class
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f
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as
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e
m
ag
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S
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m
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o
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2
.
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k
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m
icr
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etc.
I
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s
f
u
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s
t
itu
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s
i
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lu
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C
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m
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s
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c
h
a
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au
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v
id
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tex
t
o
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s
o
m
e
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er
d
i
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m
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)
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d
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Me
t
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p
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o
m
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n
a
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tr
an
s
f
o
r
m
d
o
m
ai
n
)
.
a.
Sp
atial
Do
m
ain
[
4
]
Sp
atial
d
o
m
a
in
s
teg
a
n
o
g
r
ap
h
y
in
w
h
ic
h
th
e
co
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f
id
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n
tial
in
f
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m
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s
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m
b
ed
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ed
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th
e
p
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m
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lt
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ia
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ata.
Steg
a
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ap
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i
n
s
p
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l
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o
m
ai
n
co
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s
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m
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co
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co
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p
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t.
T
h
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s
p
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m
et
h
o
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s
ar
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t
f
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eq
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y
r
ea
l
izatio
n
.
b
.
Fre
q
u
en
c
y
Do
m
ain
[
5
]
T
h
e
m
ai
n
s
tr
en
g
th
o
f
tr
an
s
f
o
r
m
d
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m
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n
tech
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iq
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s
is
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estrictio
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o
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,
m
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s
p
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r
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ain
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r
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to
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ig
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co
m
p
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eq
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[
6
]
.
T
h
r
ee
tech
n
iq
u
e
s
i
n
f
r
eq
u
en
c
y
d
o
m
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n
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n
a
m
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DC
T
(
Dis
cr
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C
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s
in
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r
an
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m
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an
s
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)
,
an
d
DFT
(
Dis
cr
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Fo
u
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ier
T
r
an
s
f
o
r
m
)
.
1
.
3
.
I
m
a
g
e
Ste
g
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no
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ra
ph
y
E
m
b
ed
d
in
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s
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r
et
d
ata
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m
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i
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co
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5
.
2.
DE
SCR
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P
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O
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O
F
VARI
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US TE
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Q
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D
2
.
1
.
P
ix
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Va
lue D
if
f
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(
P
VD)
P
ix
el
v
alu
e
d
i
f
f
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n
ci
n
g
(
P
VD)
[
6
]
b
ased
s
teg
an
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ap
h
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o
f
p
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p
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ased
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ased
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(
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{
(
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(
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(
1
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2
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2
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B
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T
h
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L
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ased
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7
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is
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f
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s
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ased
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m
a
n
y
p
er
ce
p
tib
le
d
is
to
r
tio
n
s
.
I
t
w
o
r
k
s
b
y
r
ep
laci
n
g
t
h
e
L
SB
s
o
f
r
an
d
o
m
l
y
s
elec
ted
p
ix
els
in
t
h
e
co
v
er
i
m
a
g
e
w
it
h
t
h
e
s
ec
r
et
m
ess
a
g
e
b
its
.
T
h
e
s
elec
t
io
n
o
f
p
ix
el
s
m
a
y
b
e
d
eter
m
i
n
ed
b
y
a
s
ec
r
et
k
e
y
.
T
h
e
em
b
ed
d
in
g
o
p
er
atio
n
o
f
L
SB
s
t
eg
a
n
o
g
r
ap
h
y
m
a
y
b
e
d
es
cr
ib
ed
b
y
th
e
f
o
llo
w
in
g
eq
u
ati
o
n
.
⌊
⌋
(
2
)
w
h
er
e
m
i
,
x
i
,
a
n
d
y
i
ar
e
t
h
e
i
-
t
h
m
es
s
ag
e
b
it,
t
h
e
i
-
t
h
s
elec
ted
p
ix
el
v
al
u
e
b
e
f
o
r
e
e
m
b
ed
d
in
g
an
d
th
at
a
f
ter
e
m
b
ed
d
in
g
,
r
esp
ec
ti
v
el
y
.
Ma
n
y
s
te
g
a
n
o
g
r
ap
h
ic
to
o
ls
u
s
i
n
g
t
h
e
L
SB
b
ased
s
te
g
a
n
o
g
r
ap
h
ic
tech
n
iq
u
e,
s
u
c
h
as
Ste
g
h
id
e,
S
-
to
o
ls
,
Ste
g
an
o
s
,
e
tc
.
B
y
c
h
a
n
g
i
n
g
t
h
e
L
SB
o
f
a
p
ix
el
r
esu
lts
i
n
s
m
al
l
ch
a
n
g
e
s
in
t
h
e
i
n
te
n
s
it
y
o
f
th
e
co
lo
r
s
.
T
h
ese
c
h
a
n
g
e
s
ca
n
n
o
t
b
e
id
en
tify
b
y
t
h
e
h
u
m
a
n
e
y
e,
t
h
u
s
th
e
m
e
s
s
a
g
e
is
s
u
c
ce
s
s
f
u
l
l
y
h
id
d
en
i
n
i
m
a
g
e
as
s
h
o
w
n
i
n
Fi
g
u
r
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2
.
T
h
e
p
r
o
p
o
s
ed
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o
r
ith
m
is
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n
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ten
s
io
n
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t
h
e
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o
r
it
h
m
p
r
o
p
o
s
ed
in
[
8
]
an
d
th
e
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lt
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s
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t
w
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its
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ir
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y
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n
a
Me
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s
a
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e
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te
g
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g
r
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e
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g
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r
e
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u
r
e
3
.
B
lo
ck
Diag
r
a
m
o
f
P
r
o
p
o
s
ed
I
m
ag
e
S
teg
a
n
o
g
r
ap
h
y
3
.
1
.
E
m
be
dd
i
ng
P
ro
ce
s
s
Flo
w
C
h
ar
t o
f
p
r
o
p
o
s
ed
em
b
ed
d
in
g
p
r
o
ce
s
s
s
h
o
w
n
i
n
Fi
g
u
r
e
4
:
Fig
u
r
e
4
.
Flo
w
C
h
ar
t o
f
P
r
o
p
o
s
ed
E
m
b
ed
d
in
g
P
r
o
ce
ss
3
.
2
.
E
m
be
dd
i
ng
Alg
o
rit
h
m
a.
R
ea
d
th
e
i
m
ag
e
f
ile
o
f
s
ize
m
*
m
.
(
I
org
)
o
f
m
*
m
b.
Ma
k
e
its
f
r
a
m
e
s
(
R
ed
,
Gr
ee
n
,
B
lu
e)
.
I
org
=
(
I
R
, I
G
, I
B
)
c.
Div
id
e
f
r
a
m
es i
n
to
b
lo
ck
s
o
f
4
*
4
p
i
x
el
g
r
o
u
p
.
d.
Select
b
lo
ck
f
r
o
m
ea
c
h
f
r
a
m
e
o
n
e
b
y
o
n
e.
e.
C
alcu
late
av
er
a
g
e
d
if
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er
en
ce
v
alu
e
u
s
i
n
g
eq
u
a
tio
n
g
iv
e
n
b
elo
w
.
∑
|
|
(
3
)
f.
Nu
m
b
er
o
f
b
it
s
is
ca
lc
u
lated
with
d
v
al
u
e
u
s
i
n
g
g
i
v
en
r
an
g
e
t
ab
le.
g.
T
ak
e
m
e
s
s
a
g
e
an
d
co
n
v
er
t it
i
n
to
b
in
ar
y
.
h.
msg
_
b
in
= d
ec
2
b
in
(
msg
,
8
)
i.
A
p
p
l
y
L
SB
s
u
b
s
ti
tu
t
io
n
.
j.
P
ix(
1
,
n
)
= m
s
g
(
n
_
b
its
)
k.
Af
ter
s
u
b
s
tit
u
tio
n
,
r
ea
r
r
an
g
e
p
ix
el
g
r
o
u
p
s
to
f
o
r
m
s
teg
o
i
m
a
g
e.
l.
C
alcu
late
P
SNR
,
MSE
,
r
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
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8708
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C
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o
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ed
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tr
ac
tio
n
p
r
o
ce
s
s
is
ill
u
s
tr
ated
i
n
Fi
g
u
r
e
5
:
Fig
u
r
e
5
.
Flo
w
c
h
ar
t o
f
p
r
o
p
o
s
ed
ex
tr
ac
tio
n
p
r
o
ce
s
s
3
.
3
.
1
.
E
x
t
ra
ct
io
n Alg
o
rit
h
m
a.
T
ak
e
a
s
teg
o
i
m
a
g
e
o
f
s
ize
m
*
m
.
(
I
s
teg
o
)
o
f m
*
m
b.
Ma
k
e
its
f
r
a
m
e
s
(
R
ed
,
Gr
ee
n
,
B
lu
e)
.
I
s
teg
o
=
(
I
SR
, I
SG
,
I
S
B
)
c.
Div
id
e
f
r
a
m
es i
n
to
b
lo
ck
s
o
f
4
*
4
p
i
x
el
g
r
o
u
p
.
d.
Select
b
lo
ck
f
r
o
m
ea
c
h
f
r
a
m
e
o
n
e
b
y
o
n
e.
e.
Select
r
ef
er
en
ce
p
i
x
el
f
r
o
m
ea
ch
b
lo
ck
.
r
ef
-
p
ix
= [
{Rs,
Gs,
B
s
},F
r
a
me
{p
ix(
4
,
4
)
}
]
f.
Gr
o
u
p
in
g
o
f
L
SB
‟
S o
f
ea
ch
p
i
x
el
ac
co
r
d
in
g
to
v
a
lu
e
o
f
r
e
f
er
en
ce
p
ix
el.
msg
= p
ix[
(
R
s
,
G
s
,
B
s
)
,
n
]
g.
A
r
r
an
g
e
e
x
tr
ac
ted
d
ata
in
to
eig
h
t b
it a
r
r
a
y
.
h.
C
o
n
v
er
t b
in
ar
y
i
n
to
A
S
C
I
I
ch
ar
ac
ter
.
msg
_
b
in
=
b
in
2
d
ec
(
msg
,
8
)
i.
E
m
b
ed
d
ed
m
es
s
a
g
e.
4.
E
XP
E
R
I
M
E
NT
A
L
RE
SUL
T
S
T
h
e
ex
p
er
im
e
n
tal
r
es
u
lts
w
er
e
s
i
m
u
lated
in
M
A
T
L
A
B
.
Var
io
u
s
co
v
er
i
m
a
g
es
o
f
v
ar
y
in
g
ca
p
ac
ities
an
d
s
izes
w
er
e
tak
e
n
a
n
d
t
h
e
alg
o
r
ith
m
w
a
s
i
m
p
le
m
en
ted
to
e
m
b
ed
th
e
s
teg
o
i
n
f
o
r
m
ati
o
n
in
to
t
h
e
s
e
co
v
er
i
m
a
g
es.
I
t
w
a
s
o
b
s
er
v
ed
th
at
t
h
e
p
r
o
p
o
s
ed
alg
o
r
ith
m
en
ab
le
d
h
ig
h
er
n
u
m
b
er
o
f
b
its
to
b
e
in
co
r
p
o
r
ated
in
th
e
h
o
s
t
d
ata
w
it
h
o
u
t
ca
u
s
i
n
g
an
y
s
i
g
n
if
ican
t
p
er
ce
p
tib
le
ch
a
n
g
e
to
th
e
co
v
er
i
m
ag
e.
An
i
m
p
r
o
v
e
m
e
n
t
i
n
t
h
e
P
SNR
,
MSE
as
w
ell
a
s
co
r
r
elatio
n
co
e
f
f
icien
t
h
as
b
ee
n
r
eg
is
ter
ed
i
n
th
e
p
r
o
p
o
s
ed
m
e
th
o
d
.
P
er
f
o
r
m
an
ce
m
at
r
ices o
f
v
ar
io
u
s
i
m
ag
e
s
at
v
ar
y
i
n
g
ca
p
ac
it
y
is
il
lu
s
tr
ated
in
Fi
g
u
r
e
6
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
E
C
E
I
SS
N:
2
0
8
8
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mp
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5
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b
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i
s
ti
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it
h
m
a
n
d
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r
o
p
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s
ed
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o
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ith
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at
d
if
f
er
e
n
t c
ap
ac
it
y
i
s
s
h
o
w
n
i
n
T
ab
le
1
.
T
ab
le
1
.
C
o
m
p
ar
is
o
n
o
f
E
x
i
s
ti
n
g
Alg
o
r
it
h
m
a
n
d
P
r
o
p
o
s
ed
Alg
o
r
ith
m
at
Di
f
f
er
en
t
C
ap
ac
it
y
5.
CO
NCLU
SI
O
N
Fo
r
th
e
i
m
a
g
e
s
teg
a
n
o
g
r
ap
h
y
v
ar
io
u
s
m
e
th
o
d
s
h
a
v
e
b
ee
n
p
r
o
p
o
s
ed
.
I
n
th
is
p
ap
er
w
e
p
r
o
p
o
s
e
an
i
m
p
r
o
v
ed
ap
p
r
o
ac
h
o
f
i
m
a
g
e
s
teg
a
n
o
g
r
ap
h
y
t
h
at
u
s
es
s
i
x
te
en
-
p
i
x
el
d
i
f
f
er
en
ci
n
g
w
it
h
n
-
b
it
L
SB
s
u
b
s
tit
u
tio
n
.
T
h
e
p
e
r
f
o
r
m
a
n
ce
m
e
tr
ics
ar
e
in
d
icativ
e
o
f
g
o
o
d
r
esu
lts
it
lead
s
to
lo
w
er
MSE
an
d
h
ig
h
er
P
SNR
v
alu
e
s
.
T
h
e
Evaluation Warning : The document was created with Spire.PDF for Python.
I
SS
N
:
2
0
8
8
-
8708
I
J
E
C
E
Vo
l.
6
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No
.
6
,
Dec
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1
6
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RE
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NC
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S
[1
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S
.
A
ru
n
Ku
m
a
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t
a
l,
“
S
teg
a
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m
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in
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h
n
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In
ter
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l
o
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tes
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T
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n
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En
g
i
n
e
e
rin
g
a
n
d
T
e
c
h
n
o
lo
g
y
(
IJ
L
T
ET
)
,
Vo
l.
5
,
Ja
n
u
a
ry
2
0
1
5
,
p
p
.
4
2
6
-
4
3
0
.
[2
]
G.
M
o
h
it
,
“
A
No
v
e
l
T
e
x
t
S
teg
a
n
o
g
ra
p
h
y
T
e
c
h
n
iq
u
e
Ba
se
d
o
n
Htm
l
Do
c
u
m
e
n
ts”
,
In
ter
n
a
ti
o
n
a
l
J
o
u
r
n
a
l
o
f
Ad
v
a
n
c
e
d
S
c
ien
c
e
a
n
d
T
e
c
h
n
o
lo
g
y
,
Vo
l.
3
5
,
Oc
to
b
e
r
2
0
1
1
,
p
p
.
1
2
9
-
1
3
8
.
[3
]
V
.
De
e
p
a
n
k
a
r,
“
S
teg
a
n
o
g
ra
p
h
y
T
e
c
h
n
iq
u
e
s”
,
In
ter
n
a
ti
o
n
a
l
J
o
u
r
n
a
l
o
f
Eme
rg
i
n
g
Res
e
a
rc
h
in
M
a
n
a
g
e
me
n
t
&
T
e
c
h
n
o
l
o
g
y
,
Vo
l.
3
,
M
a
y
2
0
1
4
,
p
p
.
1
3
2
-
1
3
5
.
[4
]
T
.
Na
m
it
a
e
t
a
l,
“
S
p
a
ti
a
l
Do
m
a
in
Im
a
g
e
S
teg
a
n
o
g
ra
p
h
y
b
a
se
d
o
n
S
e
c
u
ri
ty
a
n
d
Ra
n
d
o
m
iza
ti
o
n
”
,
In
ter
n
a
t
io
n
a
l
J
o
u
rn
a
l
o
f
A
d
v
a
n
c
e
d
C
o
mp
u
ter
S
c
ien
c
e
a
n
d
Ap
p
li
c
a
t
io
n
s
,
V
o
l
.
5
,
2
0
1
4
,
p
p
.
1
5
6
-
1
5
9
.
[5
]
N.
Dh
in
a
h
a
ra
n
e
t
a
l,
“
T
re
n
d
s
i
n
Co
m
p
u
ter
S
c
ien
c
e
,
En
g
in
e
e
rin
g
a
n
d
I
n
f
o
rm
a
ti
o
n
T
e
c
h
n
o
lo
g
y
”
,
P
ro
c
.
o
f
F
irst
In
tern
a
ti
o
n
a
l
C
o
n
f
e
re
n
c
e
o
n
Co
m
p
u
ter S
c
ien
c
e
,
En
g
in
e
e
rin
g
a
n
d
I
n
f
o
r
m
a
ti
o
n
T
e
c
h
n
o
lo
g
y
,
S
e
p
tem
b
e
r
2
0
1
1
.
[6
]
L
.
Weiq
i
e
t
a
l,
“
A
M
o
re
S
e
c
u
re
S
teg
a
n
o
g
ra
p
h
y
b
a
se
d
o
n
A
d
a
p
ti
v
e
P
ix
e
l
-
V
a
lu
e
Dif
f
e
r
e
n
c
in
g
S
c
h
e
m
e
p
ro
p
o
se
d
t
h
a
t
P
ix
e
l
-
V
a
lu
e
Dif
f
e
re
n
c
in
g
(P
V
D)
”
,
J
o
u
rn
a
l
o
f
M
u
lt
ime
d
ia
T
o
o
ls
a
n
d
Ap
p
li
c
a
ti
o
n
s
,
V
o
l.
5
2
,
n
o
.
2
,
Ja
n
u
a
ry
2
0
1
0
,
p
p
.
4
0
7
-
4
3
0
.
[7
]
S
.
A
ru
n
Ku
m
a
r
e
t
a
l,
“
S
teg
a
n
o
g
r
a
p
h
y
in
I
m
a
g
e
s
Us
in
g
L
S
B
T
e
c
h
n
iq
u
e
”
,
In
ter
n
a
ti
o
n
a
l
J
o
u
rn
a
l
o
f
L
a
tes
t
T
re
n
d
s
i
n
En
g
i
n
e
e
rin
g
a
n
d
T
e
c
h
n
o
lo
g
y
(
IJ
L
T
ET
),
Vo
l.
5
,
Ja
n
u
a
ry
2
0
1
5
,
p
p
.
4
2
6
-
4
3
0
.
[8
]
G
a
n
d
h
a
rb
a
S
w
a
in
,
“
Dig
it
a
l
Im
a
g
e
S
teg
a
n
o
g
r
a
p
h
y
u
sin
g
Nin
e
-
P
ix
e
l
Dif
fe
re
n
c
in
g
a
n
d
M
o
d
if
ied
L
S
B
S
u
b
stit
u
ti
o
n
”
,
In
d
i
a
n
J
o
u
rn
a
l
o
f
S
c
ien
c
e
a
n
d
T
e
c
h
n
o
l
o
g
y
,
Vo
l.
7
,
S
e
p
tem
b
e
r
2
0
1
4
,
p
p
.
1
4
4
4
-
1
4
5
0
.
B
I
O
G
RAP
H
Y
O
F
AUTHO
R
Dr
M
e
e
n
a
k
s
h
i
S
Ar
y
a
is
c
u
rre
n
tl
y
w
o
rk
in
g
a
s
As
so
c
iate
P
ro
f
e
ss
o
r
a
n
d
He
a
d
o
f
th
e
De
p
a
rt
m
e
n
t
a
t
Ba
b
a
F
a
rid
Co
ll
e
g
e
o
f
En
g
in
e
e
rin
g
a
n
d
T
e
c
h
n
o
lo
g
y
.
S
h
e
c
o
m
p
lete
d
h
e
r
P
h
.
D.
i
n
th
e
a
re
a
o
f
Dig
it
a
l
I
m
a
g
e
P
ro
c
e
ss
in
g
in
th
e
y
e
a
r
2
0
1
4
.
He
r
re
sa
e
rc
h
in
tere
sts
a
re
in
th
e
f
ield
o
f
Dig
it
a
l
In
a
g
e
P
r
o
c
e
ss
in
g
a
n
d
Da
ta M
i
n
in
g
a
n
d
W
a
re
h
o
u
sin
g
.
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