一种基于均值量化的抗去同步攻击数字水印算法

基于量化调制的音频水印方案以其原理简单、操纵灵活等特点,已引起人们广泛关注,但现有方案不同程度地存在鲁棒性较差等不足之处.结合音频统计均值稳定特性及同步码技术,提出了一种新的数字音频水印嵌入算法,该算法选取稳健的16位巴克码作为同步标记,通过量化音频样本统计均值嵌入同步码,同时结合听觉掩蔽特性量化低频小波系数平均值嵌入数字水印.仿真实验结果表明,本算法不仅具有较好的不可感知性,而且对常规信号处理(MP3压缩、低通滤波、添加噪声、均衡化等)和去同步攻击(随机剪切、幅度缩放、抖动等)均具有较好的鲁棒性.     

一种基于倒谱变换的自同步音频水印算法

本文提出了一种基于倒谱变换的自同步数字音频水印算法。算法对音频载体分段后,将同步码嵌入到时域上,将水印信息嵌入到变换域上。水印的提取不需要原始音频信号,是一种盲水印算法。实验结果表明,嵌入后的水印不仅具有很好的不可感知性,而且对添加噪声、重新采样、低通滤波、重新量化和剪切攻击也具有很好的稳健性。     

基于回归型支持向量机的数字图像水印新算法

以回归型支持向量机（Support Vector Regression,SVR）理论为基础,提出一种数字图像水印新算法.该算法能够结合图像局部相关性,选取稳定的特征向量并获得SVR训练模型,进而利用SVR训练模型嵌入和提取数字水印信息.该算法以保证不可感知性和鲁棒性的良好平衡为前提,实现了数字水印的盲检测.仿真实验表明,本文算法不仅具有较好的不可感知性,而且对叠加噪声、JPEG压缩、锐化、平滑滤波、对比度增强等常规处理及扭曲、剪切等几何攻击均具有较好的鲁棒性,其整体性能明显优于现有SVM图像水印方案.     

一种新的大容量数字音频水印嵌入算法

提出了一种新的大容量数字音频水印嵌入算法．该算法具有以下特点：（1）以整型小波变换为基础，不仅降低了舍入误差，而且提高了音频水印的嵌入与检测速度；（2）采纳分段变换及整体修改策略，增强了数字水印嵌入的稳定性；（3）以灰度图像作为数字水印，不仅数据容量大，而且更具层次感和多样性；（4）以保证不可感知性和鲁棒性的良好平衡为前提，实现了数字水印的盲检测．仿真实验表明：所提出的算法不仅具有较好的不可感知性，而且对诸如重新采样、重新量化、低通滤波、MP3压缩、叠加噪声等攻击均具有较好的鲁棒性．     

基于SVR的嵌入强度自适应的图像水印算法

如何优化水印嵌入强度是数字水印研究中的关键问题，并与水印的鲁棒性和不可感知性密切相关。本文针对图像数据，基于SVR模型提出一种嵌入强度自适应的水印算法。在图像特征方面，本文选取图像的LBP算子和小波变换的低频系数，根据SSIM指标确定合适的水印嵌入强度，生成训练样本数据集并对SVR模型进行训练；在水印嵌入过程中，首先对水印进行加密等预处理，然后对图像子块进行DWT变换，运用训练好的SVR模型确定水印嵌入强度并嵌入水印，同理可根据密钥和SVR模型进行水印的提取。实验结果表明，本文提出的算法在保证图像质量和水印不可见性的前提下，能够对图像进行自适应地水印嵌入和提取，同时对噪声、压缩、剪切等攻击均具有较好的鲁棒性。     

基于音频特征的抗去同步攻击数字水印算法

抗去同步攻击的强鲁棒数字音频水印方法研究是一项富有挑战性的工作.本文结合数字音频自身特征,提出了一种基于音频内容的抗去同步攻击数字水印算法.该算法首先根据数字音频的局部能量特征,从原始载体中提取出稳定的特征点;然后以音频特征点为标识,确定用于水印嵌入的候选音频段;最后采纳量化调制策略,将数字水印嵌入到音频载体内.进行数字水印检测时,系统通过分析音频内容提取特征点,再以特征点为标识提取水印信息,水印检测无需原始音频信号参与.仿真实验结果表明,本文算法不仅具有较好的不可感知性,而且对常规信号处理(MP3压缩、低通滤波、添加噪声等)和去同步攻击(随机剪切、幅度缩放、时间延展、抖动等)均具有较好的鲁棒性.     

一种可抵抗MP3压缩的音频水印算法

提出了一种稳健的自适应混合域数字音频水印算法，该算法具有以下特点:(1)通过采纳更为稳健的同步信号及其全新嵌入策略，提高了音频水印的抗攻击能力；(2)充分利用DWT的多分辨率特性和DCT的能量压缩特性，改善了数字水印的隐藏效果；(3)结合听觉掩蔽特性自适应确定量化步长，提高了数字水印的不可感知性；(4)以保证不可感知性和稳健性的良好平衡为前提，实现了数字水印的盲检测．仿真实验表明，所提出的算法不仅具有较好的不可感知性，而且对诸如重新采样、重新量化、叠加噪声、低通滤波、随机剪切等攻击均具有较好的稳健性．特别地，该算法对于最为普通的MP3压缩攻击具有极强的抵抗能力(尤其是高压缩比下).     

采用混沌加密和重复码的复倒谱音频水印算法

针对数字音频产品版权保护问题,设计了一种基于混沌加密和重复码调制的复倒谱变换数字音频水印算法。算法把音频信号划分为包含相同采样点的若干帧,对每一帧实施复倒谱变换,将一幅包含版权信息的二值图像作为水印,利用混沌序列对其加密,再利用重复码进行纠错后嵌入到原始音频的复倒谱系数中,水印提取时不需要原始音频信号。实现了水印的盲检测。仿真实验证明,算法具有较强的鲁棒性和不可感知性。能经受添加噪声、低通滤波、重采样、重新量化、音频格式转换等常见信号的处理及攻击。     

一种新的自适应数字音频水印嵌入算法

提出了一种基于整型提升小波变换与人类听觉系统(HAS)的自适应数字音频水印嵌入算法。该算法具有4个特点。实验结果表明,该自适应数字音频水印嵌入算法不仅具有较好的透明性,而且对诸如叠加噪声、有损压缩、低通滤波、重新采样、重新量化等攻击均具有较好的鲁棒性。     

基于听觉特性的DCT域数字音频水印算法

提出一种基于听觉掩蔽效应和量化的DCT域音频水印嵌入方案,根据人耳的生理听觉特性,计算音频信号的掩蔽阈值,对获取的中低频系数量化后嵌入数字水印图像,量化步长由掩蔽阈值自适应控制,并且水印的提出和检测都不需要原始数字音频信号的参与。实验结果表明,该算法具有较好的不可感知性,并且对压缩、滤波等操作具有较强的鲁棒性。     

A New Adaptive Digital Audio Watermarking Based on Support Vector Regression

On the basis of support vector regression (SVR), a new adaptive blind digital audio watermarking algorithm is proposed. This algorithm embeds the template information and watermark signal into the original audio by adaptive quantization according to the local audio correlation and human auditory masking. The procedure of watermark extraction is as follows. First, the corresponding features of template and watermark are extracted from the watermarked audio. Then, the corresponding feature of template is selected as training sample to train SVR and an SVR model is returned. Finally, the actual outputs are predicted according to the corresponding feature of watermark, and the digital watermark is recovered from the watermarked audio by using the well-trained SVR. Experimental results show that our audio watermarking scheme is not only inaudible, but also robust against various common signal processing (such as noise adding, resampling, requantization, and MP3 compression), and also has high practicability. In addition, the algorithm can extract the watermark without the help of the original digital audio signal, and the performance of it is better than other SVM audio watermarking schemes.     

基于音频统计特性的数字水印嵌入算法

结合数字音频时频域统计特性及同步码技术, 提出了一种可有效抵抗去同步攻击的混合域数字音频水印嵌入算法. 该算法首先结合数字水印与同步码(大小), 对原始音频载体进行分段处理, 并将每个音频数据段分割成两部分用于嵌入同步码与水印信息; 然后利用时间域音频样本统计特性, 将同步码信息嵌入到音频样本的统计均值上; 最后根据频率域小波系数统计特性, 将数字水印嵌入到低频小波系数的平均值内.     

A pseudo-Zernike moment based audio watermarking scheme robust against desynchronization attacks

Desynchronization attack is known as one of the most difficult attacks to resist, for it can desynchronize the location of the watermark and hence causes incorrect watermark detection. It is a challenging work to design a robust audio watermarking scheme against desynchronization attacks. Based on pseudo-Zernike moment and synchronization code, we propose a new digital audio watermarking algorithm with good auditory quality and reasonable resistance toward desynchronization attacks in this paper. Firstly, the origin digital audio is segmented and then each segment is cut into two parts. Secondly, with the spatial watermarking technique, synchronization code is embedded into the statistics average value of audio samples in the first part. And then, map 1D digital audio signal in the second part into 2D form, and calculate its pseudo-Zernike moments. Finally, the watermark bit is embedded into the average value of modulus of the low-order pseudo-Zernike moments. Meanwhile combining the two adjacent synchronization code searching technology, the algorithm can extract the watermark without the help from the origin digital audio signal. Simulation results show that the proposed watermarking scheme is not only inaudible and robust against common signals processing such as MP3 compression, noise addition, resampling, re-quantization, etc., but also robust against the desynchronization attacks such as random cropping, amplitude variation, pitch shifting, jittering, etc.     

基于Blakley方案的音频水印分存算法

提出了一种基于Blakley密钥共享方案的音频水印分存算法。算法将密钥分存的思想引入到音频水印算法中,将水印分存到音频数据的不同段中,检测时只需提取出部分水印信息就可以恢复出原始水印。算法同时采用了Bark码来解决剪切攻击带来的同步问题,并利用逼近信号统计特征和纠错码技术来提高算法的鲁棒性。实验证明,算法具有较强的抗剪切攻击能力。     

High payload multi-channel dual audio watermarking algorithm based on discrete wavelet transform and singular value decomposition

Digital watermarking technology is concerned with solving the problem of copyright protection, data authentication, content identification, distribution, and duplication of the digital media due to the great developments in computers and Internet technology. Recently, protection of digital audio signals has attracted the attention of researchers. This paper proposes a new audio watermarking scheme based on discrete wavelet transform (DWT), singular value decomposition (SVD), and quantization index modulation (QIM) with a synchronization code embedded with two encrypted watermark images or logos inserted into a stereo audio signal. In this algorithm, the original audio signal is split into blocks, and each block is decomposed with a two-level DWT, and then the approximate low-frequency sub-band coefficients are decomposed by SVD transform to obtain a diagonal matrix. The prepared watermarking and synchronization code bit stream is embedded into the diagonal matrix using QIM. After that, we perform inverse singular value decomposition (ISVD) and inverse discrete wavelet transform (IDWT) to obtain the watermarked audio signal. The watermark can be blindly extracted without knowledge of the original audio signal. Experimental results show that the transparency and imperceptibility of the proposed algorithm is satisfied, and that robustness is strong against popular audio signal processing attacks. High watermarking payload is achieved through the proposed scheme.     

Pseudo-zernike moments-based audio content authentication algorithm robust against feature-analysed substitution attack

Content-based audio content authentication algorithms provide a method to solve the veracity and integrity of audio content. On the basic of pseudo-Zernike moments, an audio content authentication algorithm robust against feature-analysed substitution attack is proposed, which is aimed at some insecure issues in the existing content-based audio content authentication schemes. Firstly, the audio signal is cut into non-overlapping frames and each frame is divided into two segments, and each segment is scrambled. Then, synchronization codes generated by pseudo random sequence and watermark bits generated by pseudo-Zernike moments are embedded in the first and second segment, respectively, which are completed by quantizing the modulus of pseudo-Zernike moments. The scrambled segments used to generate and extract watermark are unknown to attackers. So, it is difficult for attackers to get the watermark generated and extracted to perform feature-analysed substitution attack. The synchronization code and watermark embedding method proposed is inaudible and has excellent ability to tolerance against common signal processing operations. Compared with the existing audio watermark algorithms based on pseudo-Zernike moments, the algorithm increases the embedding capacity and improves the security of the watermarking system.     

A robust digital audio watermarking scheme using wavelet moment invariance

It is a challenging work to design a robust audio watermarking scheme against various attacks. Wavelet moment invariances are new features combining the moment invariant features and the wavelet features, and they have some excellent characteristics, such as the ability to capture local information, robustness against common signal processing, and the linear relationship between a signal and its wavelet moments etc. Based on wavelet moment and synchronization code, we propose a new digital audio watermarking algorithm with good auditory quality and reasonable resistance against most attacks in this paper. Firstly, the origin digital audio is segmented and then each segment is cut into two parts. Secondly, with the spatial watermarking technique, synchronization code is embedded into the statistics average value of audio samples in the first part. And then, map 1D digital audio signal in the second part into 2D form, and calculate its wavelet moments. Finally, the watermark bit is embedded into the average value of modulus of the low-order wavelet moments. Meanwhile combining the two adjacent synchronization code searching technology, the algorithm can extract the watermark without the help from the origin digital audio signal. Simulation results show that the proposed watermarking scheme is not only inaudible and robust against common signals processing such as MP3 compression, noise addition, resampling, and re-quantization etc., but also robust against the desynchronization attacks such as random cropping, amplitude variation, pitch shifting, and jittering etc.     

基于回归型支持向量机的小波域盲水印算法

以回归型支持向量机（Support Vector Regression,SVR）理论为基础,提出了一种新的基于SVR的小波域盲水印算法。算法核心思想是先对图像进行小波分解,然后利用图像小波分解后的子图系数之间的关系和图像局部相关性获得SVR训练模型,并利用SVR训练模型在小波域嵌入和提取水印。该算法以保证鲁棒性和透明性的良好平衡为前提,实现了数字水印的盲检测。仿真实验表明,该文算法不仅具有较好的透明性,而且对JPEG压缩和一般的图像处理具有很强的鲁棒性,其整体性能明显优于现有基于SVM的空间域上的水印算法。