TITLE:
Watermarking Images in the Frequency Domain by Exploiting Self-Inverting Permutations
AUTHORS:
Maria Chroni, Angelos Fylakis, Stavros D. Nikolopoulos
KEYWORDS:
Watermarking Techniques; Image Watermarking Algorithms; Self-Inverting Permutations; 2D Representations of Permutations; Encoding; Decoding; Frequency Domain; Experimental Evaluation
JOURNAL NAME:
Journal of Information Security,
Vol.4 No.2,
April
23,
2013
ABSTRACT:
In this work we propose efficient codec algorithms for watermarking
images that are intended for uploading on the web under intellectual property
protection. Headed to this direction, we recently suggested a way in which an
integer number w which being
transformed into a self-inverting permutation, can be represented in a two
dimensional (2D) object and thus, since images are 2D structures, we have proposed
a watermarking algorithm that embeds marks on them using the 2D representation
of w in the spatial
domain. Based on the idea behind this technique, we now expand the usage of
this concept by marking the image in the frequency domain. In particular, we
propose a watermarking technique that also uses the 2D representation of
self-inverting permutations and utilizes marking at specific areas thanks to
partial modifications of the image’s Discrete Fourier Transform (DFT). Those
modifications are made on the magnitude of specific frequency bands and they
are the least possible additive information ensuring robustness and
imperceptiveness. We have experimentally evaluated our algorithms using various
images of different characteristics under JPEG compression. The experimental
results show an improvement in comparison to the previously obtained results
and they also depict the validity of our proposed codec algorithms.