IMAGE WATERMARKING AND EXTRACTION

THIS APP USES THE DISCRETE WAVELET TRANSFORM AND EMBEDS A WATERMARK IN THE HOST IMAGE.
THERE IS A KEY AND A UNIQUE PASSCODE GENERATED IN THE SPECIFIED DIRECTORY.
IF ANY MISTAKE TAKES PLACE, THE IMAGE MIGHT CHANGE OR THE BRIGHTNESS MAY VARY.

IF KEY+PASSCODE IS WRONG THEN IMAGE WOULD BE COMPLETELY DIFFERENT.
IF ONLY THE PASSCODE IS WRONG THEN BRIGHTNESS WOULD VARY.

PASSCODE IS UNIQUE FOR EACH IMAGE (ONE PER IMAGE)
IN THE SECURITY MODE ONE CAN USE AN AADHAR CARD (INDIA) ONLY.
IT WILL ENCODE A BARCODE IN AN AADDHAR CARD WHICH WILL BE THE UID NUMBER. THE BARCODE IS GENERATED USING THE CODE UPLOADED ON FILE EXCHANGE BY -
PEDRO VILLENA

PLS NOTE THIS FEATURE IS COMPATIBLE WITH R2020A ONWARD.

THE ZIP FILE HAS THE .mlappinstall files of 2 apps (encoder + decoder)

THE DATA IS PRESENT IN THE GIVEN LINK-
https://drive.google.com/drive/folders/1A2QJo22sxbGQWeYUJt2_W73XJ2YEWF5G?usp=sharing
ALSO, THE WEB VERSIONS OF THE APPS ARE THERE FOR NON-MATLAB USERS IN THE ABOVE LINK

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ORIGINAL IDEA OF WATERMARKING WAS TAKEN FROM THE FOLLOWING WEBSITE
https://www.imageeprocessing.com/2014/06/digital-image-water-marking-part-1.html#:~:text=MATLAB%20CODE%3A,-%25Read%20the%20Blog&text=OIm(Sz(1)%3ASz,Watermark%20in%20the%20centre')%3B

AND A FEW FRIENDS OF MINE NAMED -:

KEVAL SHAH
RISHI MOLIA
POOJA NAMBIAR

IDEA OF WAVELET TRANSFORM FOR ENCODING AND DECODING WATERMARKS WAS TAKEN FROM-
https://www.researchgate.net/publication/324053161_Robust_hybrid_watermarking_techniques_for_different_color_imaging_systems

OTHER URLS (INCLUDING PAPERS) REFERRED FOR THIS ARE-:

%https://www.hindawi.com/journals/mpe/2017/7401845/
%http://www.ee.sunysb.edu/~cvl/ese558/s2005/Reports/Lin%20Liu/ese558report_LinLiu.pdf
%https://www.ijcsmc.com/docs/papers/September2014/V3I9201499a32.pdf
%https://in.mathworks.com/matlabcentral/fileexchange/46866-watermark-dct
%https://www.ripublication.com/aeee_spl/aeeev4n5spl_11.pdf
%https://www.researchgate.net/publication/252315721_Going_Beyond_RGB_How_to_Create_Color_Composite_Images_that_Convey_the_Science

%https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8981817

%https://stackoverflow.com/questions/18816841/obtaining-opposite-diagonal-of-a-matrix-in-matlab
%https://in.mathworks.com/matlabcentral/answers/374562-how-can-you-resize-the-image-without-deforming-the-image
%https://arxiv.org/pdf/1405.3207.pdf
%https://en.wikipedia.org/wiki/Hadamard_transform
%https://in.mathworks.com/matlabcentral/answers/52163-help-me-how-to-convert-rgb-image-to-yuv
%https://link.springer.com/article/10.1007/s12652-019-01500-1
%https://link.springer.com/article/10.1007/s11042-018-5814-y
%https://www.researchgate.net/publication/324053161_Robust_hybrid_watermarking_techniques_for_different_color_imaging_systems (MAIN)

%https://in.mathworks.com/matlabcentral/answers/281640-sum-values-in-a-cell-array
%https://in.mathworks.com/matlabcentral/answers/41762-delete-row-from-matrix
%https://www.sciencedirect.com/science/article/abs/pii/0022072887803005
%https://www.jstor.org/stable/2290595?seq=1

%https://scialert.net/fulltext/?doi=itj.2010.1369.1375

%https://www.sciencedirect.com/topics/engineering/hadamard-transform

%http://freesourcecode.net/matlabprojects/58441/simulation-of-dct%2C-walsh%2C-hadamard%2C-haar-and-slant-transform-using-variable--block-sizes-in-matlab#.X8zO4i8RpaI

%https://in.mathworks.com/matlabcentral/fileexchange/41333-simulation-of-dct-walsh-hadamard-haar-and-slant-transform-using-variable-block-sizes?focused=3784758&tab=function
%https://www.mathworks.com/matlabcentral/answers/267301-inverse-opposite-of-diff-function

%Huffman idea
%https://www.mathworks.com/matlabcentral/answers/423105-huffman-encoding-for-image-compression
%https://www.mathworks.com/matlabcentral/answers/423107-huffman-encoding-for-image

%https://www.researchgate.net/publication/312621677_Image_Watermarking_based_on_Huffman_Coding_and_Laplace_Sharpening/link/5886d379a6fdcc6b79193fb0/download
%http://www.enggjournals.com/ijcse/doc/IJCSE10-02-02-08.pdf
% https://www.mathworks.com/matlabcentral/answers/296620-how-to-separate-integers-and-decimal-numbers-from-given-values
% https://stackoverflow.com/questions/499939/how-to-extract-the-decimal-part-from-a-floating-point-number-in-c
% https://userweb.cs.txstate.edu/~mb92/papers/dcc06.pdf
%https://www.intechopen.com/books/cyberspace/blind-wavelet-based-image-watermarking

% https://www.mathworks.com/matlabcentral/answers/460378-how-to-insert-an-element-after-each-number-in-a-vector
% https://www.mathworks.com/matlabcentral/fileexchange/45062-barcode-generator-gs1-128 (BARCODE GENERATION TAKEN FROM HERE)