ADAPTIVE DIGITAL WATERMARKING ALGORITHM BASED ON GOLD CODES AND WAVELET TRANSFORM

摘要

An adaptive digital watermarking algorithm was proposed, in which Gold codes was applied, and the watermark was inserted into the wavelet domain of the carrier image according to the analysis of human visual system. The robustness and efficiency of the algorithm is enhanced because of the introduction of CDMA. At first, Gold codes were generated by m-sequences, and the watermark was encoded through CDMA technique, then the encoded information was inserted into the wavelet domain adaptively according to JND (Just Noticeable Difference). Experiment results show that the embedded watermark is invisible, and can resist to Gaussian Noise, JPEG compression and median filtering.