Tree Energy Differentiation (TED) Based Wavelet Watermarking for Digital Images

Abstract

In this paper, we present a novel differential energy watermarking algorithm called free Energy Differentiation (TED) based on the wavelet tic., structure. The wavelet coefficients of the image arc divided into disjoint twos called wavelet trees. A wavelet tree consist,: of 21 coefficients and is divided into 6 blocks. One watermark bit is embedded into one wavelet tree using the energy differentiation between coefficients of each block. lit addition, the Contrast sensitive Function (CSF) of human visual system is also considered fur better weighting in watermarking. Using, this approach, we cat cheek each wavelet tree to verify the watermark existence for copyright protection and ownership verification. The experimental results demonstrate the effectiveness of TED algorithm in terms of robustness and imperceptibility of watermarking.