一种离散余弦变换域抗同步攻击的音频水印算法

An anti-synchronization attack audio watermarking algorithm in DCT domain

设计了一种抵抗同步攻击的音频水印方案。首先证明音频均值是一个受TSM(time scale modification)操作稳定的特征量,然后利用音频均值生成水印,并将其嵌入4级离散余弦变换(DCT)分解低频系数的统计均值中。为避免同步攻击引起的水印同步结构连续偏移问题,提取水印过程中采用帧长不固定的可变帧长分帧方法;为实现水印的盲检测,水印的嵌入、提取通过量化的方法实现;为保证水印的不可听性,利用信噪比(SNR)控制水印的嵌入强度。实验结果表明,提出的方法在抵抗常规信号处理操作的同时,还能抵抗20%的TSM操作和1/10的抖动操作,具有很好的鲁棒性。

An audio watermarking scheme is designed to resist synchronization attack.Firstly,it is poved that the audio mean is a stable feature parameter for the time scale modification（TSM）operation,and then audio mean is applied to embed the watermarking in the statistical mean of the low frequency decomposition coefficients 4-level discrete cosine transform（DCT）;In order to avoiding the continuous shifting of watermarking synchronization structure caused by means of synchronization attacks,the variable frame length dividing frame method is used in the process of extracting watermark;In order to realizing watermarking blind detection,watermarking is embedded and extracted to audio by quantization method,and signal-to-noise ratio（SNR）is used to control the watermarking strength for watermarking inaudibility.The experimental results show that the proposed method is robust to the operation of conventional signal processing,and even can resist 20% TSM and 1/10 dithering operation.