Digital Audio Watermarking Technique Research Articles

Audio watermarking technique in frequency domain: comparative study MDCT Vs DCT

Digital watermarking is the art of hiding information in a digital document in order to protect it. The inserted mark and the marked document can be an image, an audio or a video. In this article, we will present a comparative study between two variants of a digital audio watermarking technique operating in the frequency domain. In the first variant, the time-frequency mapping is performed by Modified Discrete Cosine Transform (MDCT). For the second variant, the time-frequency mapping is performed by the Discrete Cosine Transform (DCT). We will study the contribution of each transformation, point of view robustness against different types of attacks delivered by Stirmark audio, imperceptibility by using a statistical approach by calculating the SNR and an objective approach by calculating the ODG notes given by PEAQ and capacity of insertion. Finally, to highlight our results, we will compare the two variants of the proposed technique with some other existing techniques.

Comparative Studies of various Digital Image and Audio Watermarking Techniques

Comparative Studies of various Digital Image and Audio Watermarking Techniques

Digital Speech Watermarking Based on Linear Predictive Analysis and Singular Value Decomposition

In this paper different digital audio watermarking techniques have been proposed. Currently, more attention is given to combination of Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) techniques for watermarking purpose. Available DWT–SVD audio watermarking techniques cannot be applied to speech signals efficiently. However, Linear Predictive Analysis (LPA) technique can model digital speech signals (20–30 ms) in more flexible and efficient ways than DWT. In this paper, a novel digital speech watermarking technique is proposed by applying both LPA and SVD. Quantization Index Modulation (QIM) is further applied to embed the watermark bits. The experimental results show that not only time and memory were reduced significantly as compared to different DWT–SVD audio watermarking techniques, but also the proposed technique was more robust and imperceptible for speech watermarking than other DWT–SVD audio watermarking techniques.

A Robust Audio Watermarking Technique Operates in MDCT Domain based on Perceptual Measures

the review presents a digital audio watermarking technique operating in the frequency domain with two variants. This technique uses the Modified Discrete Cosine Transform (MDCT) to move to the frequency domain. To ensure more inaudibility, we exploited the proprieties of the psychoacoustic model 1 (PMH1) of MPEG1 encoder layer I in the first variant and those of psychoacoustic model 2 (PMH2) of MPEG1 encoder Layer III in the second alternative to search the places for insertion of the watermark. In both variants of the technique, the bits of the mark will be duplicated to increase the capacity of insertion then inserted into the least significant bit (LSB). For more reliability in the detection phase, we use an error correction code (Hamming) on the mark. Next, to analyze the performance of the proposed technique, we perform two comparative studies. In the first, we compare the proposed digital audio watermarking technique with her two variants and those achieved by Luigi Rosa and Rolf Brigola, ‘which we download the M-files of each’. The technique developed by Luigi Rosa operates in the frequency domain but using the Discrete Cosine Transform (DCT) as transformation and that proposed by Rolf Brigola uses the Fast Fourier Transform (FFT). We studied the robustness of each technique against different types of attacks such as compression / decompression MP3, stirmark audio attack and we evaluated the inaudibility by using an objective approach by calculating the SNR and the ODG notes given by PEAQ. The robustness of this technique is shown against different types of attacks. In the second, we prove the contribution of the proposed technique by comparing the payload data, imperceptibility and robustness against attack MP3 with others existing techniques in the literature

Digital Audio Water Marking Technology Research

The basic concept of digital audio watermarking technology prompt digital audio watermarking techniques as evidence of legal products used for protection of intellectual property rights. Robustness and perceptual, detectable, embedded data volume index, to extract the watermark does not need the raw data is the basic requirement of digital audio watermarking technology. The concept of information hiding, the multiple meanings of the two aspects of a narrow sense and a broad understanding. Digital audio watermarking has strict process and the basic model, is used in the protection of intellectual property rights, and other fields.

A digital audio watermarking scheme using selective mid band DCT coefficients and energy threshold

In this paper, two blind digital audio watermarking technique are proposed according to the payload requirement which uses discrete cosine transform (DCT). In our method the watermark is embedded into the selected mid band coefficients of the DCT transformed audio. The selected coefficients are middle band DCT coefficients which are modified and quantized through the average energy of the selected sub frame for watermark embedding. The mid band frequency components are selected through experiments such that the effect of mp3 compression and the common signal processing operation has a minimum effect on these coefficients. Original audio will not be required for extraction of the watermark. To adapt to the mp3 attack a preprocessing step is embedded which did an mp3 conversion of the audio and convert again the audio to the original format prior to embedding. Also embedding is done on the selected blocks which satisfies minimum energy threshold. Experiments show that our scheme produces imperceptible audios and the watermarked audio is robust against common signal processing attacks.

Digital Audio watermarking using perceptual masking: A Review

Sharing electronic files on the internet has grown extremely fast over the last decade due to large volume of the mobile phones. These files include diverse forms of multimedia such as music, video, text and image. However digital files can be easily copied distributed and altered leading to copyright infringement. It is this ease of reproducing that causes copyright violations. Composers and distributors are more focused on implementing digital watermarking techniques to protect their material against illegal copying. Digital audio watermarking technique protects intellectual property by embedding watermark data into the audio file and recovering that information without affecting the audio quality of the original data. In this paper an overview of fundamental concepts of digital audio watermarking using perceptual masking is presented which includes a watermarking procedure to embed copyright protection into digital audio by directly modifying the audio samples. The procedure directly exploits temporal and frequency perceptual masking to guarantee that the embedded watermark is inaudible and robust. The watermark is constructed by breaking each audio clip into smaller segments and adding a perceptually shaped pseudo-random sequence. The noise-like watermark is statistically undetectable to prevent unauthorized removal. Keywords -Audio watermarking, Copyright Protection, Embedding, Frequency Masking Perceptual masking, Psychoacoustic Auditory Model, Temporal Masking.

Indoor Positioning System Using Digital Audio Watermarking

Recently, a number of location-based services such as navigation and mobile advertising have been proposed. Such services require real-time user positions. Since a global positioning system (GPS), which is one of the most well-known techniques for real-time positioning, is unsuitable for indoor uses due to unavailability of GPS signals, many indoor positioning systems (IPSs) using WLAN, radio frequency identification tags, and so forth have been proposed. However, most of them suffer from high installation costs. In this paper, we propose a novel IPS for real-time positioning that utilizes a digital audio watermarking technique. The proposed IPS first embeds watermarks into an audio signal to generate watermarked signals, each of which is then emitted from a corresponding speaker installed in a target environment. A user of the proposed IPS receives the watermarked signals with a mobile device equipped with a microphone, and the watermarks are detected in the received signal. For positioning, we model various effects upon watermarks due to propagation in the air, i.e., delays, attenuation, and diffraction. The model enables the proposed IPS to accurately locate the user based on the watermarks detected in the received signal. The proposed IPS can be easily deployed with a low installation cost because the IPS can work with off-the-shelf speakers that have been already installed in most of the indoor environments such as department stores, amusement arcades, and airports. We experimentally evaluate the accuracy of positioning and show that the proposed IPS locates the user in a 6m by 7.5m room with root mean squared error of 2.25m on average. The results also demonstrate the potential capability of real-time positioning with the proposed IPS.

Speech authentication system using digital watermarking and pattern recovery

The objective of this paper is to detect speech forgery using digital audio watermarking and pattern recovery techniques. A digital watermark pattern has been attached with the speech signal to detect three kinds of alterations or forgeries such as substitution, insertion, and removal. The watermark pattern will be modified if some changes have been made to the speech contents. Modification and forgery can be measured and detected by pattern recovery. The proposed method uses the cyclic pattern embedding to overcome synchronizing problems of previous detection techniques. In addition, pattern recovery enhances the robustness to compression. This method has been tested and verified using six recording devices, which was used for collecting verbal data. The speech signals were sampled at the rate of 8 kHz and digitized at 16 bits resolution. Randomly chosen regions were substituted, removed, and compressed in MP3 at the rate of 16 kbps as well as in CELP at the rate of 11.5 kbps. The experiment shows the perfect detection for three kinds of forgeries and it proved the validity of the proposed method.

Digital audio watermarking in the cepstrum domain

We propose a digital audio watermarking technique in the cepstrum domain. We insert a digital watermark into the cepstral components of the audio signal using a technique analogous to spread spectrum communications, hiding a narrow band signal in a wideband channel. In our method, we use pseudo-random sequences to watermark the audio signal. The watermark is then weighted in the cepstrum domain according to the distribution of cepstral coefficients and the frequency masking characteristics of the human auditory system. Watermark embedding minimizes the audibility of the watermark signal. The embedded watermark is robust to multiple watermarks, MPEG audio coding and additive noise.