An adaptive image watermarking in wavelet-domain by embedding shift-orthogonal finite-length sequences

As a solution of copyright protection of image, an image watermarking based on wavelet transform and shift-orthogonal finite-length(SOFL) sequences is proposed. SOFL sequence has the characteristics of shift-orthogonality and mean 0, variance 1. The security of SOFL sequence is higher than pseudo random sequence because of the parameters used to generate the sequence. Watermark embedding is based on the characteristics of the human visual system (HVS) in wavelet-domain. In the process of watermark detection the normalized correlation function is used. The experimental results show that the proposed watermarking scheme is perceptual invisible and robust against attacks such as JPEG compression, additive noise, filtering and cropping.