Implementasi Steganografi Least Significant Bit (LSB) dan End Of File (EOF) Pada File Citra

37

Lampiran 1. Fungsi Utama

function varargout = UTAMA(varargin)
% UTAMA M-file for UTAMA.fig
%
UTAMA, by itself, creates a new UTAMA or raises
the existing
%
singleton*.
%
%
H = UTAMA returns the handle to a new UTAMA or
the handle to
%
the existing singleton*.
%
%
UTAMA('CALLBACK',hObject,eventData,handles,...)
calls the local

%
function named CALLBACK in UTAMA.M with the
given input arguments.
%
%
UTAMA('Property','Value',...) creates a new
UTAMA or raises the
%
existing singleton*. Starting from the left,
property value pairs are
%
applied to the GUI before UTAMA_OpeningFcn gets
called. An
%
unrecognized property name or invalid value
makes property application
%
stop. All inputs are passed to UTAMA_OpeningFcn
via varargin.
%

%
*See GUI Options on GUIDE's Tools menu. Choose
"GUI allows only one
%
instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES
% Edit the above text to modify the response to help
UTAMA
% Last Modified by GUIDE v2.5 20-Jun-2016 10:36:31
% Begin initialization code - DO NOT
gui_Singleton = 1;
gui_State = struct('gui_Name',
'gui_Singleton',
'gui_OpeningFcn',
...
'gui_OutputFcn',
...

EDIT

mfilename, ...
gui_Singleton, ...
@UTAMA_OpeningFcn,
@UTAMA_OutputFcn,

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38

'gui_LayoutFcn', [] , ...
'gui_Callback',
[]);
if nargin && ischar(varargin{1})
gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
[varargout{1:nargout}] = gui_mainfcn(gui_State,
varargin{:});
else
gui_mainfcn(gui_State, varargin{:});

end
% End initialization code - DO NOT EDIT
% --- Executes just before UTAMA is made visible.
function UTAMA_OpeningFcn(hObject, eventdata, handles,
varargin)
% This function has no output args, see OutputFcn.
% hObject
handle to figure
% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
% varargin
command line arguments to UTAMA (see
VARARGIN)
% Choose default command line output for UTAMA
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);

% UIWAIT makes UTAMA wait for user response (see
UIRESUME)
% uiwait(handles.utama);
% --- Outputs from this function are returned to the
command line.
function varargout = UTAMA_OutputFcn(hObject,
eventdata, handles)
% varargout cell array for returning output args (see
VARARGOUT);
% hObject
handle to figure
% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)

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% Get default command line output from handles
structure
varargout{1} = handles.output;
% --- Executes on button press in tombolEnkripsi.
function tombolEnkripsi_Callback(hObject, eventdata,
handles)
% hObject
handle to tombolEnkripsi (see GCBO)
% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
respon = EMBEDDING('Title','embedding'); %enkripsi
% --- Executes on button press in tombolDekripsi.
function tombolDekripsi_Callback(hObject, eventdata,
handles)
% hObject
handle to tombolDekripsi (see GCBO)

% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
respon = EXTRACTION('Title','extranction');
% --- Executes on button press in tombolKeluar.
function tombolKeluar_Callback(hObject, eventdata,
handles)
% hObject
handle to tombolKeluar (see GCBO)
% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
close;

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Lampiran 2. Embedding
function varargout = EMBEDDING(varargin)
% embedding M-file for embedding.fig
%
embedding, by itself, creates a new embedding or
raises the existing
%
singleton*.
%
%
H = embedding returns the handle to a new
embedding or the handle to
%
the existing singleton*.
% --- Executes on button press in proses.
function proses_Callback(hObject, eventdata, handles)
% hObject
handle to proses (see GCBO)

% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
%INPUT GAMBAR
gambar = handles.Citra.RGB;
RGB = [gambar(:,:,2); gambar(:,:,1); gambar(:,:,3)];
%INPUT PESAN
pesan = handles.plainteks;
panjangPesan = length (pesan);
charPjgLSB = char(pjgLSB);
pesanLSB = [charPjgLSB, pesanLSB];
pesanLSB = uint8(pesanLSB);
[barisPesanLSB, kolomPesanLSB] = size(pesanLSB);
counter = [1 1];
[baris, kolom, rgb] = size(RGB);
besarGambar = baris*kolom;
banyakPesan = kolomPesanLSB*8;
if banyakPesan > besarGambar

msgbox({'INPUT GAMBAR BERUKURAN LEBIH
BESAR.'},'Message','modal');
else
for i=1:kolomPesanLSB
binerPesanLSB = dec2bin (pesanLSB(i),8);
r = 1;
lokasi = counter;
for i=1:8

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var(i) = RGB(counter(1), counter(2), r);
counter(2) = counter(2) + 1;
if counter(2) > kolom
counter(2) = 1;
counter(1) = counter(1)+1;
end
lokasi(1,end+1) = counter(1);

lokasi(1,end+1) = counter(2);
end
var1
var3
var5
var7

=
=
=
=

dec2bin(var(1),8);
dec2bin(var(3),8);
dec2bin(var(5),8);
dec2bin(var(7),8);

var2
var4
var6
var8

var1(8) = binerPesanLSB(1);
binerPesanLSB(2);
var3(8) = binerPesanLSB(3);
binerPesanLSB(4);
var5(8) = binerPesanLSB(5);
binerPesanLSB(6);
var7(8) = binerPesanLSB(7);
binerPesanLSB(8);
var1
var3
var5
var7

=
=
=
=

bin2dec(var1);
bin2dec(var3);
bin2dec(var5);
bin2dec(var7);

var2
var4
var6
var8

=
=
=
=

dec2bin(var(2),8);
dec2bin(var(4),8);
dec2bin(var(6),8);
dec2bin(var(8),8);

var2(8) =
var4(8) =
var6(8) =
var8(8) =
=
=
=
=

bin2dec(var2);
bin2dec(var4);
bin2dec(var6);
bin2dec(var8);

RGB(lokasi(1),lokasi(2),r)=var1;
RGB(lokasi(3),lokasi(4),r)=var2;
RGB(lokasi(5),lokasi(6),r)=var3;
RGB(lokasi(7),lokasi(8),r)=var4;
RGB(lokasi(9),lokasi(10),r)=var5;
RGB(lokasi(11),lokasi(12),r)=var6;
RGB(lokasi(13),lokasi(14),r)=var7;
RGB(lokasi(15),lokasi(16),r)=var8;
gambar= RGB;
end
RGB;
ukuran = size(RGB);
baris = ukuran(1);
baris = baris/3;
kolom = ukuran(2);
G = RGB(1:baris, 1:kolom);
R = RGB((baris+1):(baris*2), 1:kolom);
B = RGB(baris*2+1:baris*3, 1:kolom);

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gambarBaru = cat(3,R,G,B);
end
%PESAN EOF pesanEOF = pesan(pjgLSB+1:panjangPesan);
pesanEOF = double(pesanEOF);
penanda1 = double ('zx');
pesanEOF = [penanda1 pesanEOF 'zx'];
[d e] = size(pesanEOF);
awal = gambarBaru;
cover = gambarBaru;
cover = double(cover);
awal = double(awal);
[b k c] = size(cover);
x = k;
status = 1;
status2 = false;
while (~status2)
x = x+1;
for i = 1:1:k
cover(i,x,1) = pesanEOF(status);
status = status+1;
if(status>e)
status2 = true;
break;
end
cover(i,x,2) = pesanEOF(status);
status = status + 1;
if (status > e)
status2 = true;
break;
end
cover(i,x,3) = pesanEOF(status);
status = status + 1;
if (status > e)
status2 = true;
break;
end
end
if status2 == true
break;
end
end
handles.stego1 = uint8(cover);
axes(handles.gambarHasil);

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Lampiran 3. Extraction
function varargout = EXTRACTION(varargin)
% extraction M-file for extraction.fig
%
extraction, by itself, creates a new extraction
or raises the existing
%
singleton*.
% --- Executes on button press in proses.
function proses_Callback(hObject, eventdata, handles)
% hObject
handle to proses (see GCBO)
% eventdata reserved - to be defined in a future
version of MATLAB
% handles
structure with handles and user data (see
GUIDATA)
gambar = handles.Citra.RGB;
RGB = [gambar(:,:,2); gambar(:,:,1); gambar(:,:,3)];
[baris, kolom, rgb] = size(RGB);
counter = [1 1];
r = 1;
lokasi = counter;
for k=1:1
for i=1:8
var(i) = RGB(counter(1), counter(2), r);
counter(2) = counter(2)+1;
if counter(2) > kolom
counter(2) = 1;
counter(1) = counter(1)+1;
end
lokasi(1,end+1)=counter(1);
lokasi(1,end+1)=counter(2);
end
var1
var3
var5
var7

=
=
=
=

dec2bin(var(1),8);
dec2bin(var(3),8);
dec2bin(var(5),8);
dec2bin(var(7),8);

pesan(k,1)=var1(8);
pesan(k,3)=var3(8);
pesan(k,5)=var5(8);
pesan(k,7)=var7(8);

var2
var4
var6
var8

=
=
=
=

dec2bin(var(2),8);
dec2bin(var(4),8);
dec2bin(var(6),8);
dec2bin(var(8),8);

pesan(k,2)=var2(8);
pesan(k,4)=var4(8);
pesan(k,6)=var6(8);
pesan(k,8)=var8(8);

end
pesan= bin2dec(pesan);
pesan = native2unicode(pesan);
panjangCipherteks = uint8(pesan);
for k=1:panjangCipherteks

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for i=1:8
var(i) = RGB(counter(1), counter(2), r);
counter(2) = counter(2)+1;
if counter(2) > kolom
counter(2) = 1;
counter(1) = counter(1)+1;
end
lokasi(1,end+1)=counter(1);
lokasi(1,end+1)=counter(2);
end
var1 = dec2bin(var(1),8); var2 = dec2bin(var(2),8);
var3 = dec2bin(var(3),8); var4 = dec2bin(var(4),8);
var5 = dec2bin(var(5),8); var6 = dec2bin(var(6),8);
var7 = dec2bin(var(7),8); var8 = dec2bin(var(8),8);
pesan(k,1)=var1(8); pesan(k,2)=var2(8);
pesan(k,3)=var3(8); pesan(k,4)=var4(8);
pesan(k,5)=var5(8); pesan(k,6)=var6(8);
pesan(k,7)=var7(8); pesan(k,8)=var8(8);
end
pesan= bin2dec(pesan);
pesan = char(pesan);
cipherteks = pesan';
%EOF
cover = double(gambar);
[b k c] = size(cover);
penanda1 = ('zx');
penanda1 = double(penanda1);
penanda1;
x = k;
kondisi = 0;
for i = 1:1:k
tanda = [cover(1,i,1) cover(1,i,2)];
tanda = double(tanda);
if tanda == penanda1
kondisi = 1;
indeks = i;
break;
end
end
if kondisi == 1
for l = 1:1:indeks-1
for t = 1:1:b
for rgb = 1:1:3
gambarku (t,l,rgb)=cover(t,l,rgb);
end
end

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end;
gambarku = uint8(gambarku);
sss=1;
teks =[];
for i = indeks:1:k
for j=1:1:b
teks = [teks char(cover(j,i,1))];
sss = sss+1;
teks = [teks char(cover(j,i,2))];
sss = sss+1;
teks = [teks char(cover(j,i,3))];
sss = sss+1;
end
end
posisi = 3;
a = length(teks);
for i=3:a-1
posisi1 = teks(i);
posisi2 = teks(i+1);
if (posisi1 == 'z')
if(posisi2=='x')
b=3;
b=i;
end
end
end;
baru=[];
for i=3:b
tekss = teks(i);
baru = [baru tekss];
end
baru;
tampung=[];
for i=1:(length(baru)-1)
if baru(i) == 'z' && baru(i+1) =='x'
break
end
tampung = [tampung baru(i)];
end
tampung;
end
tampung;
handles.cipherteks = pesan;
guidata(hObject, handles)
set(handles.inputPesan,'string',pesan)

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