DocumentCode :
3518380
Title :
Maintaining image quality when watermarking grayscale comic images for electronic books
Author :
Yamada, Takaaki ; Ebisawa, Ryu ; Takahashi, Yoshiyasu
Author_Institution :
Yokohama Res. Lab., Hitachi, Ltd., Yokohama, Japan
fYear :
2011
fDate :
26-29 July 2011
Firstpage :
322
Lastpage :
327
Abstract :
Digital watermarking of comic images effectively protects the copyright of the content in electronic book applications. The characteristics of comic images were analyzed to determine the effect of digital watermarking on the line shapes. Modification of the shape edges by conventional watermarking methods can degrade image quality because the human eye is sensitive to the edges. The analysis revealed that slight changes in the black pixels in a comic image are barely perceived by the human eye when the image is displayed on a tablet PC. A method was then developed for embedding watermarks that minimizes modification of the white pixels compared to modification of the black ones. Experimental evaluation showed that this method improves the quality of watermarked grayscale comic images. Watermark robustness was almost the same as that with the conventional method in an assumed use case.
Keywords :
copyright; electronic publishing; image colour analysis; image watermarking; copyright protection; digital watermarking; electronic books; grayscale comic image watermarking; image quality maintenance; shape edge modification; tablet PC; Gray-scale; Humans; Image color analysis; Image quality; Robustness; Transform coding; Watermarking;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Industrial Informatics (INDIN), 2011 9th IEEE International Conference on
Conference_Location :
Caparica, Lisbon
Print_ISBN :
978-1-4577-0435-2
Electronic_ISBN :
978-1-4577-0433-8
Type :
conf
DOI :
10.1109/INDIN.2011.6034896
Filename :
6034896
Link To Document :
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