基于CFF码和Ⅰ码的抗合谋数字指纹编码

Anti-collusion Digital Fingerprint Coding Based on CFF Code and Ⅰ Code

随着抗合谋参数值增大,CFF码的编码效率呈下降趋势。为解决该难题,提出一种新的抗合谋数字指纹编码方案,并设计相应的编码生成算法和检测算法。生成算法以小参数构建的CFF码为内码、Ⅰ码为外码生成级联编码,编码效率等同于嵌入CFF码的编码效率,降低了编码难度。检测算法在确定编码所在的CFF子块位置后,对指纹特征码字位置进行跟踪从而发现叛逆者。在基于非对称数字指纹的音频盗版追踪系统上进行测试,结果表明,该方案保持了CFF码抗多种类型合谋攻击的特性,叛逆者追踪成功率超过80%,且未发生误判现象,能为依法制裁叛逆者提供法律证据。

As anti-collusion parameter values increase,Cover Free Family（CFF）code coding efficiency is on the decline. In order to solve the difficult problem,this paper presents a new anti-collusion digital fingerprint coding scheme,designs the code generation algorithm and detection algorithm. The former encodes the new code with the small parameter CFF code for internal code and I code for outer code,of which coding efficiency is equivalent for embedding the CFF code coding efficiency and effectively. The latter first explores the location which the inspected code is in the CFF internal code block, then tracks fingerprint characteristic codeword position to identify traitor. Test results on the asymmetric digital fingerprint audio piracy tracking system show that the new code can keep the characteristic that the CFF code resistances a variety of collusion attack, the success rate of traitor tracing is above 80%,no misjudgment phenomenon happen and can provide non-repudiation legal evidence in which traitor is sentenced by the law.