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

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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 EDIT gui_Singleton = 1;

gui_State = struct('gui_Name', mfilename, ... 'gui_Singleton', gui_Singleton, ... 'gui_OpeningFcn', @UTAMA_OpeningFcn, ...

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'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

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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

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

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

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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)

%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;

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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 = 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);

var1(8) = binerPesanLSB(1); var2(8) = binerPesanLSB(2);

var1 = bin2dec(var1); var2 = bin2dec(var2); var3 = bin2dec(var3); var4 = bin2dec(var4); var5 = bin2dec(var5); var6 = bin2dec(var6); var7 = bin2dec(var7); var8 = 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);

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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

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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)

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;

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 = native2unicode(pesan); panjangCipherteks = uint8(pesan);

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for i=1:8

var(i) = RGB(counter(1), counter(2), r); counter(2) = counter(2)+1;

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

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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;

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)