Image Watermarking Based on the Discrete Wavelet Transform Statistical Characteristics

The current paper proposes a robust watermarking method for still images that embeds a binary watermark into the detail subbands of the image wavelet transform. The perceptually significant coefficients are selected for each subband using a different threshold. The threshold is computed based on the statistical analysis of the wavelet coefficients. For greater invisibility of the mark, the approximation subband is left unmodified. The watermark is embedded several times to achieve robustness. The method is tested against different types of attacks (lossy compression, AWGN, scaling, cropping, intensity adjustment, filtering and collusion attack). The proposed method was compared with a state-of-the-art watermarking method, highlighting its performances