Audio watermarking by spreading echo in time domain using pseudo noise gray sequence

Digital multimedia technology has shown a significant progress day to day in various fields such as entertainment, computer vision, security etc. hence, the distribution and use of multimedia data is much easier and faster. In such an open environment, it is convenient to get the access to various information sources. In present time, several issues are arising such as information security, information authentication, ownership or copyright protection with multimedia contents. Therefore, watermarking is breakthrough technique for resolving these issues for digital multimedia content like image, audio and video. In this paper, to improve the weak points of conventional echo hiding and overcome the problem of less security, we propose an audio watermarking technique based on pseudo-random gray sequences as a confidential key. To satisfy and maximize both imperceptibility and robustness, proposed audio watermarking algorithm based on pseudo-random gray sequences embed multi bits by spreading echo in time domain. The imperceptibility and the robustness of proposed audio watermarking are tested using various attacks and by listening test.