Digital watermarking particle swarm optimization based on multi-wavelet

Watermark perceptibility and robustness must be ensured in order to enhance the practicality of digital watermarking. Taking human visual system characteristics into account fully, a particle swarm optimization method based on multi-wavelet digital watermarking is proposed. It utilizes Sa4 multi-wavelet to embed digital watermark, chooses intermediate frequency in embedding digital watermark adaptively according to the size of every energy mass, and uses multi-objective optimization method based on particle swarm optimization to optimize and adjust the embedded depth to obtain optimal effect. Experiments show the new proposed algorithm not only ensures the quality of watermarking-embed image and robustness against attacks, but also accelerate the operating speed relative to genetic algorithms.