抗MP3压缩的自适应音频盲水印算法

提出一种可抵抗MP3压缩的稳健的数字音频盲水印算法。该算法通过对音频小波域的近似分量进行分段以嵌入水印。水印提取时按音频特征实现自适应重分段,同时自动调整提取强度,解决了音频特征在MP3压缩前后不一致的矛盾,并实现了盲提取。实验结果显示该算法能有效抵抗MP3压缩、重采样、低通滤波和叠加白噪声等多种攻击。     

针对MP3压缩域比例因子的音频水印算法

分析了MP3码流中比例因子相关信息及其在解码过程中的作用,提出了一种MP3压缩域音频水印算法。该算法能对比例因子进行合理选择,从而有效控制水印嵌入对原始音频的影响,具有良好的听觉透明性,利用选择条件实现了自适应和隐同步。仿真实验表明,该算法不仅具有良好的听觉透明性和较强的鲁棒性,而且嵌入和提取的速度快,能满足实时需求。     

MP3压缩域音频的自适应水印算法

针对MP3编码方式和帧结构进行分析,利用帧中的比例因子提出了一种压缩域水印算法。算法通过引入帧变化分析步骤,很好地实现了水印的自适应嵌入。对于不同的系统要求,还可以通过修改门限信噪比的值[SNRlim]按需进行水印嵌入,使算法具有更大灵活性。同时在牺牲一定的嵌入空间前提下,实现了水印信息的自同步。实验表明,对于不同风格的音乐,该水印算法具有很好的不可听性。     

基于声道低频能量比的MP3压缩域音频水印算法

为了解决目前大多音频水印算法在应用于MP3音频时存在的效率低下、鲁棒性与不可感知性较难平衡等问题,提出基于MP3帧声道间低频能量的压缩域音频水印算法。该算法的嵌入和提取过程可分别在MP3压缩和解压缩的过程中完成,能大大提高水印的嵌入提取效率。而且由于低频能量具有较好的稳定性,算法利用MP3编解码过程中生成的改进离散余弦变换（MDCT）系数计算得到声道内低频能量,将左右声道内低频能量之比以固定步长量化,最终根据量化结果调整相应的MDCT系数实现水印嵌入;同时,结合不同比例因子频带能量的占比在计算声道内低频能量前对水印嵌入频带进行了筛选,从而能保证水印鲁棒性与不可感知性的平衡。实验显示,该算法可以在维持原始音频可听性的基础上实现对各种类型攻击较好的鲁棒性,尤其是可以抵抗MP3重压缩的攻击。     

基于压缩域的MP3音频数字水印算法

结合MP3编码特性,提出一种用于MP3版权保护的音频数字水印算法。该算法直接在压缩域中进行水印信息嵌入与提取,通过修改MP3比特流中的比例因子嵌入水印信息,无需MP3编解码过程。实验结果表明,该算法嵌入水印时不改变音频文件大小,提取水印时无需原始音频文件,其能在保证较好感知透明性的同时,具有较低的计算复杂度和较好的实时性。     

能够压缩MP3的DietMP3

随着网络带宽的增加,新歌手的涌现,网虫硬盘里的MP3歌曲也随之越来越多。有什么软件可以把硬盘里3GB的MP3在不改变音质的情况下变成2GB呢?DietMP3给你一个完美的答复。它可以在保持MP3音质的情况下把MP3文件减小到30％到70％。而且支持批量处理文件,操作方便。     

一种MP3音乐强健数字水印的实现方法

提出了一个基于MP3音频数据的强健数字水印的实现方法。针对音频的特性，利用其三个相邻Section间能量的变化关系，嵌入数字水印而不影响音频的品质，分别承受MP3压缩、低通滤波、标准化处理、D／A转换和信号裁剪的攻击，依然能够保持数字水印的完整性。在对音频数据认证时，该数字水印侦测及取回技术不需原始音频信号，就能将数字水印数据快速取出。同时在数字水印中应用错误更正码和同步码搜寻方法，使得当MP3音乐遭受攻击时，能大大提高水印数据的复原率。     

高品质MP3压缩有绝招

如今，MP3可谓是司空见惯的玩意了，就连家中的VCD，DVD机都可以支持MP3播放了，提到编码MP3，相信大多数的朋友都会选择Lame，压缩MP3时，最容易损失高频部分，但Lame作为一个免费编码引擎，其编码出来的MP3不权音色纯正而且音域宽广，特别低音和细节部分表现不错。并且支持VBR（可变码率）以及joint     

Robust and efficient content-based digital audio watermarking

This paper proposes a set of digital watermarking schemes for WAV audio, WAV-table synthesis audio and compressed audio. The watermark embedding scheme is closely related to audio content and based on the human auditory system. The experimental results in listening and robustness illustrate that the proposed watermarking schemes can achieve an optimal balance between audibility and robustness of the watermarked audio. The proposed methods are also very useful and effective for copyright protection, tracing illegal distribution and other applications.     

基于心理声学模型的自适应量化同步数字音频水印算法

针对传统的固定步长量化方法对不同种类音频载体适应性较差的缺点,基于心理声学模型,在获取的语音信号的DCT域的低频系数中量化地嵌入水印信息,量化步长由掩蔽阈值自适应控制,以满足水印的盲检测。同时引入了同步信号的思想,利用同步信号和水印序列号定位水印的嵌入位置。实验结果表明,该算法不仅具有较好的不可感知性,而且对诸如低通滤波、有损压缩、重采样和剪裁等攻击均具有较好的顽健性。     

一种新的用于音频认证数字水印算法

为确保数字音频数据感知意义上的完整性,提出了一种新的音频认证水印算法。该算法把原始音频分帧,每帧分为两节,在第一节时域中嵌入同步码,将第二节进行DCT变换,计算邻帧关系向量,并将其作为水印信息嵌入其他帧第二节的DCT中频系数。认证时,计算邻帧关系误差,据事先设定的阈值来判断音频是否被窜改,若遭受窜改,可进行窜改定位。仿真实验表明,该算法在无原始水印参与的情况下,不仅可以实现音频媒体的完整性认证,而且窜改定位准确。     

数字音频水印主要算法的研究与比较

对目前音频水印中的主要算法进行了系统的描述,并对其在不可见性、鲁棒性、计算复杂度以及嵌入量四个方面作了比较.最后总结了当前音频水印技术存在的问题,并对其发展进行了展望.     

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DWT的盲音频水印算法研究

提出了一种基于离散小波变换的盲音频数字水印算法,该算法采取分段重复嵌入方式在能量最强的小波系数内隐藏水印信号。仿真实验结果表明,该算法具有较强的鲁棒性和不可感知性,能有效抵御各种常见攻击,并且在水印检测时不需要原始的音频信号。     

A robust watermarking scheme for 3D triangular mesh models

Copyright protection of digital media has become an important issue in the creation and distribution of digital content. As a solution to this problem, digital watermarking techniques have been developed for embedding specific information identifying the owner in the host data imperceptibly. Most watermarking methods developed to date mainly focused on digital media such as images, video, audio, and text. Relatively few watermarking methods have been presented for 3D graphical models. In this paper we propose a robust 3D graphical model watermarking scheme for triangle meshes. Our approach embeds watermark information by perturbing the distance between the vertices of the model to the center of the model. More importantly, to make our watermarking scheme robust against various forms of attack while preserving the visual quality of the models our approach distributes information corresponds to a bit of the watermark over the entire model, and the strength of the embedded watermark signal is adaptive with respect to the local geometry of the model. We also introduce a weighting scheme in the watermark extraction process that makes watermark detection more robust against attacks. Experiments show that this watermarking scheme is able to withstand common attacks on 3D models such as mesh simplification, addition of noise, model cropping as well as a combination of these attacks.     

关于能量比较的数字音频盲水印方案

提出了一种关于能量比较的数字音频盲水印方案,该方案具有以下特点：根据人类听觉系统掩蔽特性,通过能量比较自适应地寻找最佳水印嵌入点;利用离散余弦变换（Discrete Cosine Transform,DCT）的能量压缩特性,提高数字水印的隐藏效果;实现音频数字水印的高透明性和高鲁棒性的同时,实现水印的盲检测。实验结果表明,算法不但保持了在各种攻击下较好的或更好的鲁棒性,定性和定量两方面的分析,也都显示了嵌入水印后的音频信号可以更好地保留原音频信号的感知质量。