Perceptual mask estimation from watermarked images
Sergi Ventosa, Elisa Sayrol, Josep Vidal · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003
In this paper, the influence of the estimated perceptual mask from the watermarked image is analyzed with the purpose of decreasing the probability of error in detection. We concentrate on a well known perceptual model that has been applied to 8x8 block-wise DCT coefficients. A new procedure based on extracting the mask of the original image from the watermarked image is developed. A closed form solution is derived to estimate the coefficients of the original image. The mask in then computed from these coefficients. The model can also be recursively estimated. Results show that the proposed solution outperforms those solutions based on not considering at all the perceptual mask in detection or on applying the same procedure that was used when embedding the watermark but using the watermarked image instead of the original image.