扩频CDMA水印性能分析及其多小波域内的应用研究

Performance Analysis of Spread Spectrum CDMA Watermarking and Applied Research in Multiwavelet Domain

通过对扩频码分多址(CDMA)水印模型的编码及检测方法进行理论分析,阐述了信息嵌入量、扩频码长、检测错误率等指标之间存在的制约关系,并使用实验进行比较和验证.在理论分析的基础上,依据多小波分解系数优良统计分布特征和图像多小波视觉掩蔽模型,提出了一种新颖的基于多小波变换的扩频CDMA数字水印方案.理论结果与实验数据对比表明所提出的模型和算法既有较高的嵌入容量,又具有较强的鲁棒性和安全性.

By means of the theory analysis of encoding and detection methods in spread spectrum Code Division Multiple Access （CDMA） watermarking model, this paper illuminates the correlations among embedded information number, spreading code length and detection error probability, and these conclusions are compared and verified with experimentations. Furthermore, taking advantage of well-defined statistical distribution of multiwavelet coefficients and visual masking model in image multiwavelet domain, this paper presents a novel spread spectrum CDMA watermarking scheme based on multiwavelet transform. Comparing the theoretical results with the empirical data obtained by experimentation, the research demonstrates that the proposed model and algorithm provide higher embedding capacity, as well as more robust and secure against attacks.