Audio watermarking based on synergy between Lucas regular sequence and Fast Fourier Transform

Abstract

The growth of digital technology over the recent years has led to increased sending and saving of electronic media. Taking advantage of digital works without observing copyright is always considered as an important threat for publishers. One of the techniques proposed for overcoming this threat is watermarking. Audio watermarking is one of the most challenging fields of watermarking, because detection of watermark in audio is much easier than in image. In this paper, a new approach is proposed for audio watermarking based on the values of energy levels in FFT domain. Despite preservation of imperceptibility and robustness, this method has also a very high capacity. The main idea of the proposed method is employing a regular embedding procedure on the basis of closing the energy of the sub-frames to Lucas math sequence, which is capable of embedding two bits in each audio frame. In addition, appropriate parameters values of the proposed approach such as frame-size and frequency-band are calculated by an intelligent recursive tuning process. Extraction process is done in a blind manner and without any need to the host original signal. In order to evaluate the proposed method, five types of audio files including Electronic, Classic, Jazz, Blues, and Rock audio files have been used in wave format. The results show that despite having a high watermarking capacity, the proposed method has a high imperceptibility and an acceptable robustness against the common attacks such as Noise Addition, 64 kbps MPEG Compression (MP3), FFT-Invert, Re-sampling etc., compared with the previous methods.