Digital audio watermarking scheme using Harmony Search Algorithm

Harmony Search Algorithm is one of the best optimization algorithm known, due to its capability of escaping the local optima and divergence free behaviour. In this paper, an optimized audio watermarking technique based on harmony search algorithm is presented. The watermark is embedded using dither modulation of the host audio signal blocks. High imperceptibility is proved to be achieved by the proposed technique through subjective test. Moreover, the technique is quite robust against variety of attacks including resampling attack, low-pass filtering, requantization and cropping effect. To improve the robustness and imperceptibility, harmony search technique has been applied on user defined quantization parameter.