A DWT-SVD based perceptual image fidelity metric for watermaking schemes

In this paper, a novel DWT-SVD perceptual fidelity metric for the evaluation of watermarking schemes is introduced. The proposed metric is based on a widely used Human Visual Model in the Discrete Wavelet Transform domain accounting for the frequency sensitivity, and the local luminance and contrast masking effects of the human eye. A relationship between the visual model in the DWT domain and the modification of the wavelet coefficients´s singular values is derived. The proposed metric is validated through subjective assessment and its performance is compared to several state-of-the-art perceptual image distortion metrics. The paper focus on Image Adaptive Watermarking methods in the Discrete Wavelet Transform Domain since they yield better results regarding robustness and transparency than other watermarking schemes.