In this work, we investigate facial anonymization techniques in 360{\deg} videos and assess their influence on the perceived realism, anonymization effect, and presence of participants. In comparison to traditional footage, 360{\deg} videos can convey engaging, immersive experiences that accurately represent the atmosphere of real-world locations. As the entire environment is captured simultaneously, it is necessary to anonymize the faces of bystanders in recordings of public spaces. Since this alters the video content, the perceived realism and immersion could be reduced. To understand these effects, we compare non-anonymized and anonymized 360{\deg} videos using blurring, black boxes, and face-swapping shown either on a regular screen or in a head-mounted display (HMD). Our results indicate significant differences in the perception of the anonymization techniques. We find that face-swapping is most realistic and least disruptive, however, participants raised concerns regarding the effectiveness of the anonymization. Furthermore, we observe that presence is affected by facial anonymization in HMD condition. Overall, the results underscore the need for facial anonymization techniques that balance both photo-realism and a sense of privacy.

翻译：本研究探讨了360度视频中的面部匿名化技术，并评估其对参与者感知的真实性、匿名化效果及临场感的影响。与传统影像相比，360度视频能够传递引人入胜的沉浸式体验，精确还原真实场景的氛围。由于整个环境被同步捕获，在公共场所录制时需要对旁观者面部进行匿名化处理。这种处理会改变视频内容，可能导致感知真实性和沉浸感降低。为探究这些影响，我们通过常规屏幕或头戴式显示器（HMD）呈现未经匿名化处理及经过模糊化、黑框遮挡和面部替换处理的360度视频进行对比。研究结果显示，不同匿名化技术的感知效果存在显著差异。我们发现面部替换技术最具真实感且干扰最小，但参与者对其匿名化有效性表示担忧。此外，我们观察到在HMD条件下，面部匿名化会影响临场感。总体而言，研究结果强调需要开发既能保持照片级真实感又能保障隐私感知的面部匿名化技术。