Optimized color image watermarking using improved firefly algorithm

The raise of technology and signal processing attacks challenges against the copyright protection. Even though there are information security techniques to deal with the copyright protection. The digital image watermarking is the key technique for the copyright protection and it is proved by our researchers. The robustness and imperceptibility are the two major qualities required for digital image watermarking. These qualities can be achieved by embedding watermark information in to optimized and selective points or places. The bio inspired firefly optimization algorithm is gained more efficiency against complex functions. In this paper, we proposed modified firefly optimization algorithm for more robustness and to increase imperceptibility of watermark embedded in the host image and also to reduce convergence time of algorithm. We examined the performance of our proposed algorithm with conventional firefly algorithm and genetic algorithm with signal processing attacks. The proposed algorithm obtains benchmark improvement on PSNR (Peak Signal to Noise Ratio), Error Bits and NC (Normalized correlation) over other similar and reported algorithms. The proposed algorithm also converges to the optimum result at faster rate.