1 Formatted Text Document Data Hiding Robust to Printing,Copying and Scanning Speaker:Fanjia Yen Adviser:Quincy Wu Date:2008/04/10
2 Outline Steganography ISM (Inter-word space) Modulation of the Inter-word Space Embedding rule Hidden Data Extraction Reference
3 Steganography What to hide Text Images Sound How to hide Embed text in text/image/sound files Embed image in text/image/sound files Embed sound in text/image/sound files
4 ISM (Inter-word space)(1/2) A space between adjacent words in a text row. There are nine inter-word spaces in the row. The actual length of the inter-word spaces in terms of number of pixels. 1 pixel -> 1 bit. For example,”1”for black and “0” for white.
5 ISM (Inter-word space)(2/2)
6 Modulation of the Inter-word Space(1/2)
7 Modulation of the Inter-word Space(2/2) After data embedding:
8 Embedding rule(1/2)
9 Embedding rule(2/2)
10 Hidden Data Extraction(1/2)
11 Hidden Data Extraction(2/2) If Φ A - Φ B >0, bit ‘1’ is extracted. If Φ A - Φ B <0, bit ‘0’ is extracted.
12 Reference wikipedia _Hiding_Robust_to_Printing_Copying_and_Scanning.pdf _Hiding_Robust_to_Printing_Copying_and_Scanning.pdf