广东工业大学学报2024，Vol.41Issue(3)：81-90,10.DOI:10.12052/gdutxb.230051
用于文本验证码生成的随机扰动优化网络
Perturbation Optimization Network with Randomization for Text-based CAPTCHAs Generation
摘要
Abstract
Text-based CAPTCHAs are friendly and easy to understand,which have been widely used in the security defense mechanism of many Internet applications.Traditional text-based CAPTCHAs improve security by distorting characters or adding background noise.With the development of deep learning,its security is threatened and over-deformed characters will bring new problems to human.To address this,this paper designs a perturbation optimization framework with randomization strategy for text-based CAPTCHAs generation(denoted as PORG),which is friendly for human but difficult for machines.Specifically,the proposed PORG devises a perturbation generation network(PGN)based on current advanced and stable perturbation methods to construct multiple perturbation factors and applies a randomization strategy to generate diverse perturbed images.In particular,the perturbation factors generated by existing methods destroy the visual information conveyed by the CAPTCHA images.To this end,a perturbation optimization network(PON)is designed to control the introduced perturbation factors by extending the distance at feature-level and narrowing the gap at global-level,which makes the generated CAPTCHAs remain human-friendly while effectively treating the attacker model.Extensive experiments conducted on eight real-world datasets show the outperformance of the proposed PORG(e.g.,attack accuracy is dropped from 90.03%to 0.12%on the CNKI dataset).关键词
文本类验证码/验证码生成/扰动优化/信息安全/图像加密Key words
text-based CAPTCHAs/CAPTCHAs generation/perturbation optimization/information security/image encryption分类
信息技术与安全科学引用本文复制引用
曾嘉琪,吴焯婷,吴泽楷,杨振国,刘文印..用于文本验证码生成的随机扰动优化网络[J].广东工业大学学报,2024,41(3):81-90,10.基金项目
国家自然科学基金资助项目(91748107,61902077) （91748107,61902077）
广东省引进创新科研团队计划项目(2014ZT05G157) （2014ZT05G157）
广东省基础与应用基础研究基金资助项目(2020A1515010616) （2020A1515010616）
广东省科技创新战略专项资金资助项目(pdjh2020a0173) （pdjh2020a0173）
广州市科技计划项目(202102020524) （202102020524）
