T EXT D IGITAL W ATERMARKING O F A M ALAYALAM T EXT D OCUMENT B ASED O N F RAGMENTS R EGROUPING S TRATEGY. Guide:Presented by: Mrs.Sreeja Sasinas Alias Haritha.Z.A Asst.Professor mcs Dept. of CSE. M.Tech CSE

P ROBLEM D EFINITION  Embedding a digital watermark into a digital text document that carries information unique to the copyright owner or the creator of the document.

I NTRODUCTION  Digital Watermarking  Text Digital Watermarking Process of embedding a digital watermark into a digital text document. Proposed in 1995 by Brassil and Low. Classification Based on the format Based on Expand space Based on semantics

 Format based Text Watermarking Three methods Line shift coding Word shift coding Feature coding  Watermark capacity and robustness of most algorithms unsatisfactory.  Enhancing robustness using Fragments regrouping strategy.

L ITERATURE S URVEY Existing works  Brassil and Maxemchunk[1] proposed coding methods that is applied either to a bitmap image or to a format file. Line shift coding Word shift coding Feature coding : altering features (eg: alter upward the vertical endlines – letters b,d,h etc.)  Merits and demerits:  Line shift coding has stronger robust but low watermarking capacity.  Word shift coding has better watermarking imperceptibility.  Feature coding is hard to implement for all kind of formats.

 R.Davarsani and K.Yaghmei[2] proposed a method to embed watermark data in Farsi letters by readjusting the amount of their slopes.  Merits: Better watermarking capacity and blindness  Demerits: Can only be used with special scripts.  Thein vui khen and A.Makur[3] introduced a word based self embedding watermarking scheme for document images coded in binary format.  Merits: Better coding of self embedding watermark.  Demerits: Extraneous detection and restoration failure.

 Qing-Cheng Li and Zhen-Hua Dong[4] Proposed a novel watermarking algorithm based on Chinese character structure.  Merits : Stronger watermarking robustness, greater watermarking capacity and better watermarking imperceptibility.  Demerits: Applicable only to Chinese language. Watermark may be attacked.  Xinmin Zhou et al.[5] proposed a semi-fragile watermarking scheme for content authentication of Chinese text documents.  Merits: More secure and reliable  Demerits :No copyright protection.

 Liu Jin’ An et al.[6] proposed a text digital watermarking for Chinese word document where inter character spaces are modified for coding.  Merits: Better capacity and efficient extraction of watermark.  Wengang Cheng et al.[7] proposed a text digital watermarking algorithm based on fragments regrouping strategy.  Merits : Stronger watermarking robustness,greater watermarking capacity and better watermarking invisibility.

P ROBLEM D ESCRIPTION  In [7] an efficient text digital watermarking algorithm is proposed based on fragments regrouping strategy.  Hash function is used for mapping watermark into document.  Format based watermarking – color feature used for embedding watermarking.  This algorithm can only be used with document in RGB color format.

S TUDY Approach Input : A Malayalam text document,a watermark. Fragment the watermark. Find the characters with loops in the text document. Embed the fragment using hash function into document characters redundantly. Expected output. A watermarked Malayalam document which is more robust,have better capacity and better invisibility.

R EFERENCES 1. J. Brassil, S. Low, N. Maxemchuk, and L. O’Gorman, “Electron marking and identification techniques to discourage document copying,” IEEE Journal on Selected Areas in Communications, VOL13, Oct.1995, pp. 1495–504, doi: / R. Davarzani and K. Yaghmaie, “Farsi Text Watermarking Based on Character Coding,” International Conference on Signal Processing Systems (ICSPS 2009), IEEE Computer Society. 3. T. V. Khen and A. Makur, “A Word Based Self-Embedding Scheme For Document Watermark,” 2006 IEEE Region 10 Conference (TENCON 2006), Institute of Electrical and Electronics Engineers Inc, Nov. 2006, pp. 906–909, doi: /TENCON Q. C. Li and Z. H. Dong, “Novel Text Watermarking Algorithm based on Chinese Characters Structure,” 2008 International Symposium on Computer Science and Computational Technology (ISCSCT), IEEE Press, Dec. 2008, pp. 348–51, doi: /ISCSCT X. M. Zhou, W. D. Zhao, S. C. Wang and R. Peng, “A semi-fragile watermarking scheme for content authentication of Chinese text documents,” nd IEEE International Conference on Computer Science and Information Technology (ICCSIT 2009), IEEE Press, Aug. 2009, pp. 439– J. A. Liu, L. He, D. Y. Fang and X. L. Gui, “A text digital watermarking for Chinese word document,” 2008 International Symposium on Computer Science and Computational Technology (ISCSCT), IEEE Press, Dec. 2008, pp. 217–20, doi: /ISCSCT A Robust Text Digital Watermarking Algorithm Based on Fragments Regrouping Strategy Wengang Cheng, Hui Feng, Cuiru Yang