The inherent freedom of exploration in virtual reality poses a challenge for directing user attention toward relevant points or objects of interest, which are potentially located outside the user's field of view or are temporarily obscured. Accordingly, guidance must sustain users' perceptual focus while preserving the sense of presence. This paper presents RippleVision, a subtle gaze guidance technique using wave-like ripples that modulate brightness with inverted polarity between the eyes and appear only within a cone from the point of interest to the gaze location. A calibration study defined detectability and acceptability thresholds for the cues, followed by a comparative user study against four state-of-the-art techniques. Results show RippleVision achieves similar search times to clearly visible techniques while significantly reducing visual dominance. Moreover, its effectiveness scales with cue visibility, improving search performance with minimal impact on perceived visual obstruction and presence.

Our ability to perceive and navigate the spatial world is a cornerstone of human experience, relying on the integration of visual and auditory cues to form a coherent sense of depth and distance. In stereoscopic 3D vision, depth perception requires fixation of both eyes on a target object, which is achieved through vergence movements, with convergence for near objects and divergence for distant ones. In contrast, auditory cues provide complementary depth information through variations in loudness, interaural differences (IAD), and the frequency spectrum. We investigate the interaction between visual and auditory cues and examine how contradictory auditory information can overdrive visual depth perception in virtual reality (VR). When a new visual target appears, we introduce a spatial discrepancy between the visual and auditory cues: the visual target is shifted closer to the previously fixated object, while the corresponding sound localization is displaced in the opposite direction. By integrating these conflicting cues through multimodal processing, the resulting percept is biased toward the intended depth location. This audiovisual fusion counteracts depth compression, thus reducing the required vergence magnitude and enabling faster gaze retargeting. Such audio-driven depth enhancement may further help mitigate the vergence-accommodation conflict (VAC) in scenarios where physical depth must be compressed. In a series of psychophysical studies, we first assess the efficiency of depth overdriving for various VR-relevant combinations of initial fixations and shifted target locations, considering different scenarios of audio displacements and their loudness and frequency parameters. Next, we quantify the resulting speedup in gaze retargeting for target shifts that can be successfully overdriven by sound manipulations. Finally, we apply our method in a naturalistic VR scenario where user interface interactions with the scene show an extended perceptual depth.

Human perception of speed is largely driven by visual cues. However, our subjective estimations of speed are influenced by several factors that can lead to deceptive cues and speed misperception. While some prior studies have explored individual effects on speed perception, such as contrast, spatial frequency, and temporal frequency, their combined influence remains underexamined, particularly in immersive VR environments. In this work, we systematically investigate the influence and interplay of four visual factors—contrast, spatial frequency, temporal frequency, and eccentricity—on human perception of speed. To this end, we conduct a psychophysical study measuring subjective speed judgments across controlled stimuli and reveal significant perceptual biases induced by these factors. Based on our collected data, we learn a model to predict the underestimation or overestimation of perceived speed from visual scene properties. We apply and validate our findings in three immersive environments and demonstrate their influence on common VR scenarios. Finally, we discuss how understanding the factors that shape speed perception can drive the design of perceptually aligned virtual environments, with potential future applications such as correcting speed misperception and conceivably mitigating visual-vestibular conflicts by modulating perceived speed.

We present MILO (Metric for Image- and Latent-space Optimization), a lightweight, multiscale, perceptual metric for full-reference image quality assessment (FR-IQA). MILO is trained using pseudo-MOS (Mean Opinion Score) supervision, in which reproducible distortions are applied to diverse images and scored via an ensemble of recent quality metrics that account for visual masking effects. This approach enables accurate learning without requiring large-scale human-labeled datasets. Despite its compact architecture, MILO outperforms existing metrics across standard FR-IQA benchmarks and offers fast inference suitable for real-time applications. Beyond quality prediction, we demonstrate the utility of MILO as a perceptual loss in both image and latent domains. In particular, we show that spatial masking modeled by MILO, when applied to latent representations from a VAE encoder within Stable Diffusion, enables efficient and perceptually aligned optimization. By combining spatial masking with a curriculum learning strategy, we first process perceptually less relevant regions before progressively shifting the optimization to more visually distorted areas. This strategy leads to significantly improved performance in tasks like denoising, super-resolution, and face restoration, while also reducing computational overhead. MILO thus functions as both a state-of-the-art image quality metric and as a practical tool for perceptual optimization in generative pipelines.

With the advent of consumer-targeted, low-cost virtual reality devices and facile authoring technologies, the development and design of experiences in virtual reality are also becoming more accessible to non-expert authors. However, the inherent freedom of exploration in these virtual spaces presents a significant challenge for designers seeking to guide user attention toward points and objects of interest. This paper proposes the new technique WarpVision, which utilizes spatial curvature to subtly guide the user's attention in virtual reality. WarpVision distorts an area around the point of interest, thus changing the size, form, and location of all objects and the space around them. In this way, the user's attention can be guided even when the point of interest is not in the immediate field of vision. WarpVision is evaluated in a user study based on a within-subjects design, comparing it to the state-of-the-art technique Deadeye. Participants completed visual search tasks across two virtual environments being supported with WarpVision at four different intensities. Results show that WarpVision significantly reduces search times compared to Deadeye. While both techniques introduce comparable levels of immersion disruption, WarpVision has a lower reported impact on the user's well-being.

A major factor resulting in cybersickness is the feeling of self-motion experienced when viewing a moving scene in Virtual Reality (VR). Current research indicates that this effect is largely created by motion in the periphery. To discover why this is the case, we investigate the influence of temporal frequency and eccentricity of a stimulus on the magnitude of perceived velocity in the periphery. Based on the perception of two-dimensional stimuli on a wide field-of-view display, we build a model to predict the scaling factor by which the perceived velocity of visual patterns deviates from the physical velocity. Further, our exploratory findings indicate no impact of gaze type on the results, suggesting our model works for both fixation and smooth pursuit scenarios. In an additional pilot study in Virtual Reality (VR), we test the accuracy of the model to predict unnoticeable object motion adaptation in 3D virtual worlds and find positive indications for a similar effect.

Virtual reality has ushered in a revolutionary era of immersive content perception. However, a persistent challenge in dynamic environments is the occurrence of cybersickness arising from a conflict between visual and vestibular cues. Prior techniques have demonstrated that limiting illusory self-motion, so-called vection, by blurring the peripheral part of images, introducing tunnel vision, or altering the camera path can effectively reduce the problem. Unfortunately, these methods often alter the user's experience with visible changes to the content. In this paper, we propose a new technique for reducing vection and combating cybersickness by subtly lowering the screen-space speed of objects in the user's peripheral vision. The method is motivated by our hypothesis that small modifications to the objects' velocity in the periphery and geometrical distortions in the peripheral vision can remain unnoticeable yet lead to reduced vection. This paper describes the experiments supporting this hypothesis and derives its limits. Furthermore, we present a method that exploits these findings by introducing subtle, screen-space geometrical distortions to animation frames to counteract the motion contributing to vection. We implement the method as a realtime post-processing step that can be integrated into existing rendering frameworks. The final validation of the technique and comparison to an alternative approach confirms its effectiveness in reducing cybersickness.

In this paper we investigate the use of electrical muscle stimulation (EMS) to trigger eye blinks for instant hand redirection in virtual reality (VR). With the rapid development of VR technology and increasing user expectations for realistic experiences, maintaining a seamless match between real and virtual objects becomes crucial for immersive interactions. However, hand movements are fast and sometimes unpredictable, increasing the need for instantaneous redirection. We introduce EMS to the field of hand redirection in VR through precise stimulation of the eyelid muscles. By exploiting the phenomenon of change blindness through natural eye blinks, our novel stimulation model achieves instantaneous, imperceptible hand redirection without the need for eye tracking. We first empirically validate the efficiency of our EMS model in eliciting full eye closure. In a second experiment, we demonstrate the feasibility of using such a technique for seamless instantaneous displacement in VR and its particular impact for hand redirection. Among other factors, our analysis also delves into the under-explored domain of gender influence on hand redirection techniques, revealing significant gender-based performance disparities.

In this paper, we propose a wavelet-based video codec specifically designed for VR displays that enables real-time playback of high-resolution 360° videos. Our codec exploits the fact that only a fraction of the full 360° video frame is visible on the display at any time. To load and decode the video viewport-dependently in real time, we make use of the wavelet transform for intra- as well as inter-frame coding. Thereby, the relevant content is directly streamed from the drive, without the need to hold the entire frames in memory. With an average of 193 frames per second at 8192 × 8192 -pixel full-frame resolution, the conducted evaluation demonstrates that our codec's decoding performance is up to 272% higher than that of the state-of-the-art video codecs H.265 and AV1 for typical VR displays. By means of a perceptual study, we further illustrate the necessity of high frame rates for a better VR experience. Finally, we demonstrate how our wavelet-based codec can also directly be used in conjunction with foveation for further performance increase.

In this paper we propose omnidirectional galvanic vestibular stimulation (GVS) to mitigate cybersickness in virtual reality applications. One of the most accepted theories indicates that Cybersickness is caused by the visually induced impression of ego motion while physically remaining at rest. As a result of this sensory mismatch, people associate negative symptoms with VR and sometimes avoid the technology altogether. To reconcile the two contradicting sensory perceptions, we investigate GVS to stimulate the vestibular canals behind our ears with low-current electrical signals that are specifically attuned to the visually displayed camera motion. We describe how to calibrate and generate the appropriate GVS signals in real-time for pre-recorded omnidirectional videos exhibiting ego-motion in all three spatial directions. For validation, we conduct an experiment presenting real-world 360° videos shot from a moving first-person perspective in a VR head-mounted display. Our findings indicate that GVS is able to significantly reduce discomfort for cybersickness-susceptible VR users, creating a deeper and more enjoyable immersive experience for many people.