Improved Robust Threshold-Based Correlation Watermarkingin DCT Domain

In this paper, an improved robust threshold-based correlation watermarking has been proposed in which for more security of watermark, it is scrambled by ATM method and reshaped to a sequence; then to reduce the change of false detection, two separate PN sequences are used to encode 1 and 0 , separately. The secured watermark is embedded into DCT blocks coefficients of the first channel from the host image which has been scrambled by ATM method and converted to CIELab channels. Experimental results, compared with the related existing methods, show that the proposed scheme not only attains satisfactory invisibility of watermarking, but also has stronger robustness against most common attacks such as JPEG compression, cropping, different noises adding, filtering, scaling etc

Keywords:

ATM , DCT blocks , CIELab channels , Threshold-based correlation watermarking