Adaptive Image Spread Spectrum Watermark Based on Improved Genetic Algorithm
Min Yang · Journal of Tianjin University Science and Technology · 2007
In order to improve the robustness and imperceptibleness of the image spread spectrum watermark algorithm,a new approach for optimization in 8×8 DCT domain using genetic algorithm(GA) was proposed.The Cox′s embedding method was amended to obtain high fidelity.And GA was used to optimize the AC coefficients adaptively,which were modified to embed the spread spectrum watermark.Performance improvement with respect to existing algorithm is obtained by GA adaptive global search.The experimental results show that some low frequency positions are the best choices for embedding the watermark,and the bands for embedding are varied to find the most suitable ones for image with different characteristics.Compared with the previous work,the proposed algorithm yields a watermark that is more invisible to human eyes and more robust to JPEG,filter,noise,scaling,and rotate attacks.