Virtual Reality (VR) systems increase immersion by reproducing users' movements in the real world. However, several works have shown that this real-to-virtual mapping does not need to be precise in order to convey a realistic experience. Being able to alter this mapping has many potential applications, since achieving an accurate real-to-virtual mapping is not always possible due to limitations in the capture or display hardware, or in the physical space available. In this work, we measure detection thresholds for lateral translation gains of virtual camera motion in response to the corresponding head motion under natural viewing, and in the absence of locomotion, so that virtual camera movement can be either compressed or expanded while these manipulations remain undetected. Finally, we propose three applications for our method, addressing three key problems in VR: improving 6-DoF viewing for captured 360° footage, overcoming physical constraints, and reducing simulator sickness. We have further validated our thresholds and evaluated our applications by means of additional user studies confirming that our manipulations remain imperceptible, and showing that (i) compressing virtual camera motion reduces visible artifacts in 6-DoF, hence improving perceived quality, (ii) virtual expansion allows for completion of virtual tasks within a reduced physical space, and (iii) simulator sickness may be alleviated in simple scenarios when our compression method is applied.

中文翻译：

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用于改进虚拟现实应用的横向摄像机运动的不易察觉的操纵

虚拟现实 (VR) 系统通过再现用户在现实世界中的动作来增加沉浸感。然而，一些作品表明，这种真实到虚拟的映射不需要精确即可传达真实的体验。能够改变这种映射有许多潜在的应用，因为由于捕获或显示硬件或可用物理空间的限制，实现准确的真实到虚拟的映射并不总是可能的。在这项工作中，我们测量了虚拟相机运动的横向平移增益的检测阈值，以响应自然观察下的相应头部运动，并且在没有运动的情况下，以便虚拟相机运动可以被压缩或扩展，而这些操作仍然未被检测到. 最后，我们为我们的方法提出了三个应用，解决 VR 中的三个关键问题：改进 360° 镜头的 6 自由度观看、克服物理限制和减少模拟器不适。我们通过额外的用户研究进一步验证了我们的阈值并评估了我们的应用程序，确认我们的操作仍然难以察觉，并表明（i）压缩虚拟相机运动减少了 6-DoF 中的可见伪影，从而提高了感知质量，（ii）虚拟扩展允许在减少的物理空间内完成虚拟任务，并且（iii）当应用我们的压缩方法时，可以在简单的场景中减轻模拟器疾病。