A Novel Invisible Color Image Watermarking Scheme using Image Adaptive
Watermark Creation and Robust Insertion-Extraction
Saraju P. Mohanty Parthasarathy Guturu
Email: smohanty@cse.unt.edu Email: guturu@unt.edu
Dept. of Computer Science and Engineering Dept. of Electrical Engineering
University of North Texas, Denton, TX 76203. University of North Texas, Denton, TX 76203.
Elias Kougianos Nishikanta Pati
Email: eliask@unt.edu Email: nishi@unt.edu
Dept. of Engineering Technology Dept. of Computer Science and Engineering
University of North Texas, Denton, TX 76203. University of North Texas, Denton, TX 76203.
Abstract
In this paper we present a robust and novel strategic in-
visible approach for insertion-extraction of a digital wa-
termark, a color image, into color images. The novelty
of our scheme lies in determining a perceptually impor-
tant sub-image in the host image so that slight tampering
of the sub-image will affect the aesthetic of the host im-
age significantly. This eliminates the possibility of water-
mark removal, which in turn makes the watermark secure
and robust. The other novel feature of our algorithm is
the creation of a compound watermark image, called effec-
tive watermark, using the input user watermark (logo) and
attributes of host image, which facilitates robust insertion-
extraction processes. The effective watermark creation con-
sists of two distinct phases: In the first phase, a statisti-
cal image is synthesized from a perceptually important sub-
image of the host image and in the second phase, a com-
pound image is created by fusing the input logo and syn-
thetic statistical image. Results of exhaustive experimen-
tation using standard benchmarks demonstrates the robust-
ness and efficacy of our approach.
1 Introduction
Many research efforts over the past decade have enabled
digital watermarking to establish itself as a potential solu-
tion for the protection of ownership rights and policing in-
formation piracy of multimedia elements like images, audio
and video. Watermarking techniques developed for images
are mainly classified into visible and invisible approaches.
While the visible methods provide means for overt asser-
tion of ownership with logos, the invisible methods provide
covert protection of these rights.
Starting with IBM’s Vatican Library project [10], visi-
ble watermarking technology quickly matured with a few
but significant contributions (e.g. [1, 18, 13, 12]) from re-
searchers. Invisible watermarking, on the other hand, is
a well addressed topic that was initiated by the research
teams of Cox [7], Craver [2] and others. Though invisible
watermarking techniques helped in making the watermark
imperceptible to human eye and less prone to attacks, seri-
ous challenges to protect the embedded watermark against
different types of attacks still persist. Many of the current
techniques use different transform domains to embed the
watermark inspired by methods of information coding and
image compression. The watermark is embedded into the
cover image using the discrete cosine transform (DCT), dis-
crete wavelet transform (DWT) and discrete fourier trans-
form (DFT).
The paper is organized as follows: The contributions of
this paper are presented in Section 2. The relevant related
research works that served as motivation for this research
work are discussed in Section 3. In Section 4 we present our
innovative strategy for invisible watermark creation. Sec-
tion 5 discusses the implantation of the compound water-
mark along with the rationale behind the approach. Sec-
tion 6 presents our scheme for non-blind extraction of in-
visible watermarks implanted using our scheme. Finally,
experimental results on the performance of our invisible wa-
termarking scheme are presented in Section 7 followed by
summary and conclusions in Section 8.