Perceptual video watermarking in the 3D-DWT domain using a multiplicative approach

A video watermarking method operating in the three-dimensional discrete wavelet transform (3D DWT) relaying on the use of a novel video perceptual mask, applied in the 3D DWT domain, is here proposed. Specifically the method consists in partitioning the video sequence into spatio-temporal units of fixed length. Then the video shots undergo a one level 3D DWT. The mark is embedded by means of a multiplicative approach using perceptual masking on the 3D DWT coefficients in order to trade off between the mark robustness and its imperceptibility. The mask we propose takes into account the spatio-temporal frequency content by means of the spatio-temporal contrast sensitivity function, the luminance, and the variance of the 3D subbands which host the mark. The effectiveness of the proposed mask is verified experimentally, thus guaranteeing a high imperceptibility of the mark. Moreover, experimental results show the robustness of the proposed approach against MPEG2 compression, MPEG4 compression, gain attack, collusion, and transcoding.