Maximum Correlation Search Based Watermarking Scheme Resilient to RST

Many of the watermarking schemes that claim resilience to geometrical distortions embed information into invariant or semi-invariant domains. However, the discretisation process required in such domains might lead to low correlation responses during watermarking detection. In this document, a new strategy is proposed to provide resilience to strong Rotation, Scaling and Translation (RST) distortions. The proposed detection process is based on a Genetic Algorithm (GA) that maximises the correlation coefficient between the originally embedded watermark and the input image. Comparisons between a previous scheme, based on Log-Polar Mapping (LPM), and the present approach are reported. Results show that even a simple insertion process provides more robustness, as well as a lower image degradation.