A robust watermarking algorithm based on content-adaptive approach was proposed to optimize the tradeoff between robustness and imperceptibility

which was characterized as follows: the entropy masking proposed by Watson etc.was constructed in wavelet domain

which was then used to constitute the integrated HVS model;three different measures

namely

energy

entropy and integrated HVS

for content-adaptive selection were constructed and investigated;repeat-accumulate（RA） code with erasure and error correction was used to tackle the synchronization issue of the exact positions for watermark embedding;and a posteriori DWT-HMM detector was utilized for watermark detection.Simula-tion results show that the proposed content-adaptive watermarking algorithm

under the same imperceptibility

has con-siderable improvement in robustness performance over the traditional one with stochastic approach.