The Study, Based On Human Auditory System In The Transform Domain Audio Watermarking Algorithm

To overcome protection against copyright problem, digital watermarking technology has been found to be a promising solution. It is a technique by which some secret information is embedded into the host signal (text, audio, image or video) that is imperceptible to human senses. The secret information may be copyright symbols, user's license or some information relative to products.This paper study digital watermarking on audio signals. But former study exists some problems, such as synchronization, blind or non-blind detection, the watermark significant or not .This paper aims at the above defects, mainly contains the several parts as follows.Firstly, this paper introduces the development of digital watermarking, talks about the background and significance of the study. Then it introduces the principle of digital watermarking, some traditional algorithms and evaluation standards.Secondly, it proposes three algorithms in transfer domain based on HAS and psychoacoustic mode of MPEG. The watermark is a 32*32 significant binary image. It contains the several parts as follows.Chapter 3 works on HAS features, propose a novel watermarking algorithm. The first step is to use FFT transform on audio signals, then find tonal components and non-tonal components and compute the global mask threshold. It chooses tonal components which are greater than mask threshold in low frequency sub-band to embed the watermark. It also brings image scrambling and pseudorandom sequence to increase the safety of the non-blind detection algorithm.Chapter 4 considers the application of real time and decrease the compute complexity. It proposes a DCT domain watermarking scheme based on artificial neural network which can effectively estimate the watermarking scale factors for each sub-band of a frame of audio signals. Then the watermarking scale factor is used in the process of embedding. Watermarking scale factors can ensure inaudibility and increases the robustness against various attacks.Chapter 5 analyze the advantages and disadvantages of the algorithms in the last two chapters, propose an adaptive watermarking based on wavelet Packet Transform and psychoacoustic mode which can get more reasonable sub-bands. The watermark strength is properly adjusted based on weighting factors derived from the proposed psychoacoustic model. The watermark is embedded in the middle frequency coefficients. It realizes blind detection by using relative detect solution and has good inaudibility and robustness.Finally, comparisons and analysis among the three algorithms are given from compute complexity, inaudibility, robustness and so on. Experimental results show that the three algorithms can preserve inaudibility and robust enough to against the different signal processing operations. In addition, the watermarking information is enough to copyright protection . All the three algorithms are feasible.