Zero-bit watermarking resisting geometric attacks based on composite-chaos optimized SVR model

The problem to improve the performance of resisting geometric attacks in digital watermarking is addressed in this paper.Based on the optimized support vector regression（SVR）,a zero-bit watermarking algorithm is presented.The proposed algorithm encrypts the watermarking image by using composite chaos with large key space and capacity against prediction,which can strengthen the safety of the proposed algorithm.By using the relationship between Tchebichef moment invariants of detected image and watermarking characteristics,the SVR training model optimized by composite chaos enhances the ability of resisting geometric attacks.Performance analysis and simulations demonstrate that the proposed algorithm herein possesses better security and stronger robustness than some similar methods.