1 2 3 4 5
0
2
4
6
8
10
12
14
16
Number of times each watermark bit is embedded for SWS
Watermarking capacity in percentage
SWS capacity
Our scheme’s capacity
Figure 5: Comparison of our scheme’s watermarking ca-
pacity with SWS.
5 CONCLUSIONS AND FUTURE
WORK
We have proposed a watermarking model for numeric
sets in this paper. The watermarking scheme embeds
one watermark bit for every γ items in the numeric
set of size n, thereby offering a watermark carrying
capacity close to n/γ. The major improvement of-
fered by our scheme is in terms of the lack of con-
straints on the characteristics of the numeric set to be
watermarked. Unlike (Sion et al., 2002), where the
numeric set to be watermarked should follow normal
distribution, the watermarking scheme is applicable
to a numeric set irrespective of it’s distribution and it
is shown that the watermark survives against data ad-
dition, deletion, distortion, re-sorting attacks as well
as secondary watermarking attacks. The capacity of
the watermarking scheme is also higher than that of
the previous scheme.
The current scheme embeds a detectable water-
mark in the numeric set and not an extractable wa-
termark. Our future work is directed towards ﬁnding
ways to embed an extractable watermark in the nu-
meric set whilst providing the same level of security
and capacity offered by our current scheme.
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