close all
clear all

height0  = 240;
width0   = 320;

height  = 1 * height0;
width   = 1 * width0;
%% citire
% citim imaginea de transport si o convertim din spatiul de culoare RGB in
% spatiul L*a*b*

img = imread('sky.jpg');
img = imresize(img, [4 * height0 + 1, 4 * width0 + 1]);
h = figure , image(img)
title('imagine originala')
print(h, '-dpng', 'steganography_imagine_originala.png');
img_lab = double(rgb2lab(img)) / 255;

h = figure , image(img_lab)
title('imagine originala in spatiul l*a*b')
%citim imaginea secreta si o convertim in gri
hid_img = imread('dog.jpeg');
hid_img = imresize(hid_img, [height,width]);
hid_img = double(rgb2gray(hid_img)) / 255;

h = figure, imshow(hid_img);
title('imagine secreta')
%% encodare
stego_a = encode_hidden_image(img_lab(:,:,2), hid_img);
stego_b = encode_hidden_image(img_lab(:,:,3), hid_img);

figure, imagesc(stego_a);
title('stego a')

stego = img_lab;
stego(:,:,2) = stego_a;
stego(:,:,3) = stego_b;

stego_rgb = lab2rgb(stego * 255);
savefile = 'steno_img.bmp'
% imwrite(stego_rgb,'stego_rgn.jpeg','jpeg','Mode','lossless','BitDepth',12);
imwrite(stego_rgb,savefile,'bmp');

%% decodare
stego_rgb_read = imread(savefile);
h = figure , image(stego_rgb_read);
title('imagine stego')

stego_jpeg = double(rgb2lab(stego_rgb_read))/255;
figure, imagesc(log(abs(fft2(stego_jpeg(:,:,2)))));

hid1 = decode_stegano_image(stego_jpeg(:,:,2));
hid2 = decode_stegano_image(stego_jpeg(:,:,3));
hid = (hid1 + hid2) / 2;

figure, imshow(hid);impixelinfo
title('imagine secretă recuperată')