一种基于取证哈希的数字视频篡改取证方法

摘要

Conventional techniques of passive video forensics are only effective for some specific tampering operations, and just provide the binary judgment about its trustworthiness. Compared with tampering detection, the processing history estimation is a deeper goal of forensics investigation. In this paper, a digital video tampering forensics scheme is proposed based on forensics hash. To estimate the processing history, it analyzes the artifacts of video tampering, and the statistical features of several video tampering such as adding/deleting motion object are extracted as side information. Forensics hash components are constructed for geometric transform estimation, adding/deleting video object and tampering localization. A video forensic hash platform is built in a modular way. Experimental results show that the proposed approach achieves the processing history estimation of many video tampering operations such as geometric transform, seam-carving based video retargeting, and object-based manipulation. Moreover, it realizes rough tampering localization with a relatively low computational complexity.%传统的视频被动取证技术通常只对特定的篡改手段有效，且只能提供其真伪的二值判断。相对于篡改检测，处理历史估计是更高层次的取证要求。该文提出一种基于取证哈希的数字视频篡改取证方法。该方法以估计视频篡改处理历史为目标，通过分析常见的视频篡改操作的表现形式，针对运动对象的增加和删除等几种篡改手段提取统计特征作为边信息，构造包括几何变换估计，运动对象增删检测和篡改定位检测等取证哈希组件，并以模块化的方式构建视频取证哈希框架。实验结果表明，该方法能够有效地实现几何变换，seam-carving内容感知缩放，添加/删除运动对象等手段的处理历史估计，能够大致定位篡改区域，且运算复杂度较低。