Audio Watermarking Based on Advanced Wigner Distribution and Important Frequency Peaks

Abstract

An algorithm in which a multi-bit watermark is embedded into the important frequency peaks of an audio file is presented. In this algorithm, an advanced Wigner distribution method is used to estimate the most significant frequency band of the audio file. This method is based on the short-time Fourier transform (STFT) and the Wigner distribution methods, and has advantages over other methods. The important frequency peaks are selected from the most significant frequency band. Once broadcasted, an audio file is subject to many attacks such as compression and quantization. However, the main feature of the audio signal is its important frequency peaks, which are invariant. We exploit this invariance to embed the multi-bit watermark into the important frequency peaks. The simulation results show that the proposed algorithm is robust to the strong attacks such as noise addition, filtering, re-sampling and MP3 compression.