Cryptography Reference
In-Depth Information
7
Adaptive Embedding and Detection
for Improved Video Watermarking
Isao Echizen
1
, Yasuhiro Fujii
1
, Takaaki Yamada
1
, and Satoru Tezuka
1
,
and Hiroshi Yoshiura
2
1
Systems Development Laboratory, Hitachi, Ltd., Kawasaki, Japan
iechizen, fujii, t-yamada, tezuka
@sdl.hitachi.co.jp
2
Faculty of Electro-Communication, The University of Electro-Communications,
Tokyo, Japan
yoshiura@hc.uec.ac.jp
Summary.
Video watermarks must maintain picture quality and withstand video
processing. Resolving the tradeoff between these conflicting requirements has been
one of the central problems of video watermarking. Previous video watermarking
methods, however, have trouble satisfying these conflicting quality and survivability
requirements because they utilize the watermarking methods for still picture and ne-
glect the properties of motion pictures. To resolve this tradeoff, we describe adaptive
video embedding and detection techniques that utilize the properties of motion pic-
tures. Motion-adaptive embedding can allocate watermarks to picture areas which
are adaptively based on motion properties of video and, statistically adaptive detec-
tion can control the accumulation of watermarks based on the statistical properties
of video to prevent degradation in the watermark signal by video processing. Exper-
imental evaluations using actual motion pictures have shown that these techniques
can be effective for resolving the tradeoff and can be widely used in the pixel-based
watermarking.
7.1 Introduction
Because of its advantages over analog video, digital video is now being pro-
vided through the Internet and digital broadcasting and on various types of
media, such as DVDs. It requires less space, is easier to process, and does not
degrade with time or repeated use. The copyrights of digital video are easily
violated because digital video can be easily copied and delivered through the
Internet or on various types of media. Video watermarking is thus becoming
an important means of copyright protection for digital video.
Video watermarking can be used to embed copyright and copy-control
information in video pictures and is expected to be used in DVD players
and recorders as well as in digital broadcasting equipment such as set-top
boxes [1, 2]. Video watermarks must survive video processing and not degrade
