<p>With the widespread availability of mobile and desktop video-editing tools, it has become increasingly feasible for individuals to alter digital evidence in ways that serve their interests. On Apple iOS and macOS platforms, the native Photos application stands out for its ability to edit videos without re-encoding them, leaving behind traces of manipulation such as metadata changes and unreferenced frames. Although many video players and commercial forensic tools overlook these meaningful artifacts, they can be crucial for revealing malicious editing behavior by a suspect. In this paper, we explore how the Photos application can be used to manipulate video files for potentially adversarial purposes and examine its impact on the underlying file structure. We then propose and implement detection methods that cover operations such as <i>trimming</i>, <i>cropping</i>, and <i>rotation</i> to identify these manipulations and recover any residual unreferenced frames. By testing various devices and operating system versions, we demonstrate the broad applicability of our approach, showing that between 1 and 245 unreferenced frames can be recovered. As a result, our research provides the forensic community with robust methods for classifying suspicious video files, identifying their editing techniques, and extracting residual data that can be valuable as evidence.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

An in-depth forensic examination of video files edited by Apple Photos

  • Junho Kim,
  • Sangjin Lee,
  • Jungheum Park

摘要

With the widespread availability of mobile and desktop video-editing tools, it has become increasingly feasible for individuals to alter digital evidence in ways that serve their interests. On Apple iOS and macOS platforms, the native Photos application stands out for its ability to edit videos without re-encoding them, leaving behind traces of manipulation such as metadata changes and unreferenced frames. Although many video players and commercial forensic tools overlook these meaningful artifacts, they can be crucial for revealing malicious editing behavior by a suspect. In this paper, we explore how the Photos application can be used to manipulate video files for potentially adversarial purposes and examine its impact on the underlying file structure. We then propose and implement detection methods that cover operations such as trimming, cropping, and rotation to identify these manipulations and recover any residual unreferenced frames. By testing various devices and operating system versions, we demonstrate the broad applicability of our approach, showing that between 1 and 245 unreferenced frames can be recovered. As a result, our research provides the forensic community with robust methods for classifying suspicious video files, identifying their editing techniques, and extracting residual data that can be valuable as evidence.