Enhance Depth Perception Research Articles

Depth Perception in Optical See-Through Augmented Reality: Investigating the Impact of Texture Density, Luminance Contrast, and Color Contrast.

The immersive augmented reality (AR) system necessitates precise depth registration between virtual objects and the real scene. Prior studies have emphasized the efficacy of surface texture in providing depth cues to enhance depth perception across various media, including the real scene, virtual reality, and AR. However, these studies predominantly focus on black-and-white textures, leaving a gap in understanding the effectiveness of colored textures. To address this gap and further explore texture-related factors in AR, a series of experiments were conducted to investigate the effects of different texture cues on depth perception using the perceptual matching method. Findings indicate that the absolute depth error increases with decreasing contrast under black-and-white texture. Moreover, textures with higher color contrast also contribute to enhanced accuracy of depth judgments in AR. However, no significant effect of texture density on depth perception was observed. The findings serve as a theoretical reference for texture design in AR, aiding in the optimization of virtual-real registration processes.

Effects of scenery frame on visual depth perception in classical Chinese gardens: A case study of the Lvyin Pavilion in Lingering Garden

Visual depth (distance) perception is a fundamental aspect of environmental cognition, as it allows people to judge the spatial scale of their surroundings. However, estimating the depth of classical Chinese gardens is challenging, especially from static viewpoints that frame the scenery. Previous studies have examined how the internal components of the scenery frame affect depth perception. Still, the role of the frame and its peripheral information as environmental background have been largely overlooked. This study investigates how depth perception at viewpoints is influenced by viewing position displacement, frame geometry, and environmental context. The authors created nine stimulus materials in a cave virtual reality environment (three image treatments × three positions). Seventy-one participants were asked to evaluate depth perception using the magnitude estimation and adjustment methods. Their eye movement behavior was also recorded using an eye-movement instrument (SensoMotoric Instruments (SMI) eye-tracking glasses, 120 Hz). The results showed that participants could perceive spatial depth differences between viewing positions even when the internal viewpoint displacement was small; frame shape did not significantly affect depth perception and gaze behavior; and peripheral visual information of the frame enhanced depth perception significantly. Moreover, the form of the environmental background, especially the position of the scenery window, strongly guided the participants’ gaze. These findings suggest that ambient visual information significantly impacts environmental experience, which landscape designers should consider.

Object Detection System

Object detection is a critical component of computer vision, with significant applications across various domains. The challenges associated with real-world images, including noise, blurring, and rotational jitter, substantially impact the performance of object detection algorithms. YOLO (You Only Look Once), an algorithm grounded in convolutional neural networks, offers real-time object detection capabilities. This paper delves into several enhancements made to the YOLO network, aimed at augmenting the precision and efficiency of object detection tasks. The advancements discussed include optimizing the architecture of YOLO to handle diverse environmental conditions and integrating state-of-the-art techniques to mitigate common image distortions. Moreover, the paper explores the application of light field cameras to enhance depth perception and object localization. By refining the YOLO network, we aim to push the boundaries of real-time detection accuracy and reliability, crucial for applications ranging from autonomous vehicles to security surveillance systems.

Enhancing Depth Perception in Single-Lens Cameras through Barrier Detection and Artificial Intelligence

Enhancing Depth Perception in Single-Lens Cameras through Barrier Detection and Artificial Intelligence

Doing more with less: Realistic stereoscopic three-dimensional anatomical modeling from smartphone photogrammetry.

Traditional teaching methods struggle to convey three-dimensional concepts effectively. While 3D virtual models and virtual reality platforms offer a promising approach to teaching anatomy, their cost and specialized equipment pose limitations, especially in disadvantaged areas. A simpler alternative is to use virtual 3D models displayed on regular screens, but they lack immersion, realism, and stereoscopic vision. To address these challenges, we developed an affordable method utilizing smartphone-based 360° photogrammetry, virtual camera recording, and stereoscopic display (anaglyph or side-by-side technique). In this study, we assessed the feasibility of this method by subjecting it to various specimen types: osteological, soft organ, neuroanatomical, regional dissection, and a dedicated 3D-printed testing phantom. The results demonstrate that the 3D models obtained feature a complete mesh with a high level of detail and a realistic texture. Mesh and texture resolutions were estimated to be approximately 1 and 0.2 mm, respectively. Additionally, stereoscopic animations were both feasible and effective in enhancing depth perception. The simplicity and affordability of this method position it as a technique of choice for creating easily photorealistic anatomical models combined with stereoscopic depth visualization.

Comparing and Contrasting Near-Field, Object Space, and a Novel Hybrid Interaction Technique for Distant Object Manipulation in VR

In this contribution, we propose a hybrid interaction technique that integrates near-field and object-space interaction techniques for manipulating objects at a distance in virtual reality (VR). The objective of the hybrid interaction technique was to seamlessly leverage the strengths of both the near-field and object-space manipulation techniques. We employed bimanual near-field metaphor with scaled replica (BMSR) as our near-field interaction technique, which enabled us to perform multilevel degrees-of-freedom (DoF) separation transformations, such as 1~3DoF translation, 1~3DoF uniform and anchored scaling, 1DoF and 3DoF rotation, and 6DoF simultaneous translation and rotation, with enhanced depth perception and fine motor control provided by near-field manipulation techniques. The object-space interaction technique we utilized was the classic Scaled HOMER, which is known to be effective and appropriate for coarse transformations in distant object manipulation. In a repeated measures within-subjects evaluation, we empirically evaluated the three interaction techniques for their accuracy, efficiency, and economy of movement in pick-and-place, docking, and tunneling tasks in VR. Our findings revealed that the near-field BMSR technique outperformed the object space Scaled HOMER technique in terms of accuracy and economy of movement, but the participants performed more slowly overall with BMSR. Additionally, our results revealed that the participants preferred to use the hybrid interaction technique, as it allowed them to switch and transition seamlessly between the constituent BMSR and Scaled HOMER interaction techniques, depending on the level of accuracy, precision and efficiency required.

Use of a Novel Beyeonics One Three-dimensional Head-mounted Digital Visualization Platform in Vitreoretinal surgeries.

Ophthalmic microscopes have been crucial in visualizing surgical fields, but their limitations in enhancing the surgical view through digital image processing have prompted the development of digital surgical microscopes. The Beyeonics One microscope, a novel digital microscope, offers ophthalmic surgeons a 3D visualization platform and an augmented reality (AR) surgical headset, potentially improving surgical decision-making and outcomes. While its initial use has been described in cataract and corneal surgeries, its application in vitreoretinal surgery remains relatively unexplored. In this interventional case series, we collected data from the medical records of patients who underwent vitreoretinal surgery using the Beyeonics One 3D visualization platform at the Tel Aviv Medical Center. A total of 36 eyes from 36 subjects were included. Surgical techniques included retinal detachment surgeries and macular surgeries, performed by experienced surgeons. The surgical visualization was facilitated by the Beyeonics One 3D head-mounted display (HMD) platform. The procedures were uneventful, and none intra- or postoperative complications were reported, and surgeons did not experience any signal delay in the real-time video. The Beyeonics One microscope offers several potential advantages in vitreoretinal surgery, including digital image processing, enhanced depth perception through the 3D HMD platform, and hands-free image control using head gestures. While this study demonstrates the feasibility and safety of the Beyeonics One microscope, addressing limitations related to hazy views and optimizing image quality are crucial for consistent visualization.

Multi-Angle Facial Recognition: Enhancing Biometric Security with a Broadly Positioned Stereo-Camera System

This study addresses the vulnerabilities of traditional monocular camera-based face recognition systems, emphasizing the need for improved security and reliability in biometric authentication under varying environmental conditions, lighting, and human poses. To counteract the risk of spoofing attacks using masks or static images, we introduce a multi-angle stereo camera system. This system is strategically designed to capture facial imagery from multiple perspectives, thereby enhancing depth perception and spatial accuracy, crucial for high-security authentication. Employing a novel image processing approach, the study integrates a Convolutional Neural Networks (CNN) with a simple Boolean operation to differentiate the landmarks detected on each camera. This method exploits CNN’s robust feature extraction capabilities and the effective usage of stereo camera, enabling precise detection and analysis of 3D facial landmarks. Such an approach significantly bolsters the system’s ability to differentiate between genuine faces and deceptive representations like masks or static images. Empirical results demonstrate that the stereo camera configuration substantially improves recognition accuracy, reducing both false positives and negatives, especially in controlled spoofing scenarios. The advanced 3D facial landmark detection further reinforces the system’s security. With its enhanced robustness and security, the developed system shows great potential for applications in areas requiring stringent identity verification, such as banking, public facilities, and smart home technologies.

User-Aware Rendering: Merging the Strengths of Device- and User-Perspective Rendering in Handheld AR

In handheld AR, users have only a small screen to see the augmented scene, making decisions about scene layout and rendering techniques crucial. Traditional device-perspective rendering (DPR) uses the device camera's full field of view, enabling fast scene exploration, but ignoring what the user sees around the device screen. In contrast, user-perspective rendering (UPR) emulates the feeling of looking through the device like a glass pane, which enhances depth perception, but severely limits the field of view in which virtual objects are displayed, impeding scene exploration and search. We introduce the notion of User-Aware Rendering. By following the principles of UPR, but pretending the device is larger than it actually is, it combines the strengths of UPR and DPR. We present two studies showing that User-Aware AR imitating a 50% larger device successfully achieves both enhanced depth perception and fast scene exploration in typical search and selection tasks.

Clinical Applications of Mixed Reality and 3D Printing in Congenital Heart Disease.

Understanding the anatomical features and generation of realistic three-dimensional (3D) visualization of congenital heart disease (CHD) is always challenging due to the complexity and wide spectrum of CHD. Emerging technologies, including 3D printing and mixed reality (MR), have the potential to overcome these limitations based on 2D and 3D reconstructions of the standard DICOM (Digital Imaging and Communications in Medicine) images. However, very little research has been conducted with regard to the clinical value of these two novel technologies in CHD. This study aims to investigate the usefulness and clinical value of MR and 3D printing in assisting diagnosis, medical education, pre-operative planning, and intraoperative guidance of CHD surgeries through evaluations from a group of cardiac specialists and physicians. Two cardiac computed tomography angiography scans that demonstrate CHD of different complexities (atrial septal defect and double outlet right ventricle) were selected and converted into 3D-printed heart models (3DPHM) and MR models. Thirty-four cardiac specialists and physicians were recruited. The results showed that the MR models were ranked as the best modality amongst the three, and were significantly better than DICOM images in demonstrating complex CHD lesions (mean difference (MD) = 0.76, p = 0.01), in enhancing depth perception (MD = 1.09, p = 0.00), in portraying spatial relationship between cardiac structures (MD = 1.15, p = 0.00), as a learning tool of the pathology (MD = 0.91, p = 0.00), and in facilitating pre-operative planning (MD = 0.87, p = 0.02). The 3DPHM were ranked as the best modality and significantly better than DICOM images in facilitating communication with patients (MD = 0.99, p = 0.00). In conclusion, both MR models and 3DPHM have their own strengths in different aspects, and they are superior to standard DICOM images in the visualization and management of CHD.

Least Restrictive Adaptation Model: Anything You Need You Can Find in the Kitchen Drawer (First printed inRE:view, 36(2), 63–69.)

Least Restrictive Adaptation Model: Anything You Need You Can Find in the Kitchen Drawer (First printed in<i>RE:view</i>, 36(2), 63–69.)

Spatial Orientation in Cardiac Ultrasound Images Using Mixed Reality: Design and Evaluation

Spatial orientation is an important skill in structural cardiac imaging. Until recently, 3D cardiac ultrasound has been visualized on a flat screen by using volume rendering. Mixed reality devices enhance depth perception, spatial awareness, interaction, and integration in the physical world, which can prove advantageous with 3D cardiac ultrasound images. In this work, we describe the design of a system for rendering 4D (3D + time) cardiac ultrasound data as virtual objects and evaluate it for ease of spatial orientation by comparing it with a standard clinical viewing platform in a user study. The user study required eight participants to do timed tasks and rate their experience. The results showed that virtual objects in mixed reality provided easier spatial orientation and morphological understanding despite lower perceived image quality. Participants familiar with mixed reality were quicker to orient in the tasks. This suggests that familiarity with the environment plays an important role, and with improved image quality and increased use, mixed reality applications may perform better than conventional 3D echocardiography viewing systems.

47‐2: Monocular Depth Perception Enhancement Based on Joint Shading/Contrast Model and Motion Parallax (JSM)

Stereoscopic 3D displays adopt a binocular depth cue to provide depth perception. However, users should be equipped with expensive special devices to appreciate depth perception based on the binocular depth cues. Also, visual fatigue induced by the stereoscopic display is still a challenging open problem. In order to overcome this limitation, this paper proposes a novel framework, JSM, to enhance monocular depth perception, significantly improving both depth volume perception and depth range perception. The proposed framework can not only provide an enhanced depth perception on any conventional 2D display devices, but also it can be applicable to the 3D display devices since it is complimentary for binocular depth cues. The qualitative evaluation, ablation study, and subjective user evaluation proved the advantages and practicability of the proposed framework.

A Comparison of Monoscopic and Stereoscopic 3D Visualizations: Effect on Spatial Planning in Digital Twins

From the user perspective, 3D geospatial data visualizations are one of the bridges between the physical and the digital world. As such, the potential of 3D geospatial data visualizations is frequently discussed within and beyond the digital twins. The effects on human cognitive processes in complex spatial tasks is rather poorly known. No uniform standards exist for the 3D technologies used in these tasks. Although stereoscopic geovisualizations presented using 3D technologies enhance depth perception, it has been suggested that the visual discomfort experienced when using 3D technology outweighs its benefits and results in lower efficiency and errors. In the present study, sixty participants using 3D technologies were tested in terms of their ability to make informed decisions in selecting the correct position of a virtual transmitter in a digital twin and a digital terrain model, respectively. Participants (n = 60) were randomly assigned into two groups, one using 3D technology engaging stereoscopic shutter glasses and the second working with standard computer screen-based visualizations. The results indicated that the participants who used shutter glasses performed significantly worse in terms of response time (W = 175.0; p &lt; 0.001, r = −0.524). This finding verifies previous conclusions concerning the unsuitability of stereoscopic visualization technology for complex decision-making in geospatial tasks.

A context analysis of bobbing and fin-flicking in a small marine benthic fish.

Most antipredator strategies increase survival of individuals by signaling to predators, by reducing the chances of being recognized as prey, or by bewildering a predator's perception. In fish, bobbing and fin‐flicking are commonly considered as pursuit‐deterrent behaviors that signal a predator that it has been detected and thus lost its surprise‐attack advantage. Yet, very few studies assessed whether such behavioral traits are restricted to the visual presence of a predator. In this study, we used the yellow black‐headed triplefin Tripterygion delaisi to investigate the association between these behaviors and the visual exposure to (a) a black scorpionfish predator (Scorpaena porcus), (b) a stone of a size similar to that of S. porcus, (c) a conspecific, and (d) a harmless heterospecific combtooth blenny (Parablennius sanguinolentus). We used a laboratory‐controlled experiment with freshly caught fish designed to test for differences in visual cues only. Distance kept by the focal fish to each stimulus and frequency of bobbing and fin‐flicking were recorded. Triplefins kept greater distance from the stimulus compartment when a scorpionfish predator was visible. Bobbing was more frequent in the visual presence of a scorpionfish, but also shown toward the other stimuli. However, fin flicks were equally abundant across all stimuli. Both behaviors decreased in frequency over time suggesting that triplefin become gradually comfortable in a nonchanging new environment. We discuss why bobbing and fin‐flicking are not exclusive pursuit‐deterrent behaviors in this species, and propose additional nonexclusive functions such as enhancing depth perception by parallax motion (bobbing) or signaling vigilance (fin‐flicking).

Three-Dimensional vs Two-Dimensional Completely Minimally Invasive 2-Stage Esophagectomy With Intrathoracic Hand-Sewn Anastomosis for Esophageal Cancer: Comparison of Intra-and Postoperative Outcomes.

Background. Completely minimally invasive esophagectomy (CMIE) has been associated with reduced morbidity compared to open esophagectomy in the treatment of esophageal cancer. Three-dimensional (3D) vision can enhance depth perception during minimally invasive surgery when compared to two-dimensional (2D) vision. We aimed to compare outcomes from 2-stage CMIEs when performed in 2D vs 3D. Method. All consecutive 2-stage CMIEs performed for esophageal or gastroesophageal junctional cancer at a single-centre between 2016 and 2018 were identified from a prospectively maintained database. All operations were completed in either 2D or 3D. All esophagogastric anastomoses were hand-sewn thoracoscopically. Intraoperative and postoperative clinical parameters were compared between 2D and 3D CMIE. Results. Overall, 98 patients underwent a 2-stage CMIE, of which 59 (60.2%) were in 2D and 39 (39.8%) in 3D. Median operative blood loss was less in the 3D group compared to the 2D group (283mls vs 409mls, P = .016). A higher number of lymph nodes were retrieved from 3D CMIE (30 vs 25, P = .010). The median duration of surgery was 407minutes (interquartile ranges (IQR): 358-472minutes) and 426minutes (IQR: 369-509minutes) when performed in 2D and 3D, respectively (P = .162). There were no significant intergroup differences in 30-day postoperative complications, short-term mortality, and hospital stay. Conclusion. We report reduced blood loss and higher lymph node yield when performing 3D CMIE than 2D CMIE. Other intraoperative and postoperative clinical outcomes were similar in both groups. A randomized controlled trial is needed to validate these findings of superior outcomes from CMIE performed in 3D over 2D.

Improved Delineation of Cardiac Pathology Using a Novel Three-Dimensional Echocardiographic Tissue Transparency Tool

Accurate visualization of cardiac valves and lesions by three-dimensional (3D) echocardiography is integral for optimal guidance of structural procedures and appropriate selection of closure devices. A new 3D rendering tool known as transillumination (TI), which integrates a virtual light source into the data set, was recently reported to effectively enhance depth perception and orifice definition. We hypothesized that adding the ability to adjust transparency to this tool would result in improved visualization and delineation of anatomy and pathology and improved localization of regurgitant jets compared with TI without transparency and standard 3D rendering. We prospectively studied 30 patients with a spectrum of structural heart disease who underwent 3D transesophageal imaging (EPIQ system, Philips) with standard acquisition and TI with and without the transparency feature. Six experienced cardiologists and sonographers were shown randomized images of all three display types in a blinded fashion. Each image was scored independently by all experts using a Likert scale from 1 to 5, while assessing each of the following aspects: (1) ability to recognize anatomy, (2) ability to identify pathology, including regurgitant jet origin, (3) depth perception, and (4) quality of border delineation. TI images with transparency were successfully obtained in all cases. All experts perceived an incremental value of the transparency mode, compared with TI without transparency and standard 3D rendering, in terms of ability to recognize anatomy (respective scores: 4.5±1.1 vs 4.1±1.1 vs 3.6±1.1, P<.05), ability to identify pathology (4.1±1.1 vs 3.9±1.2 vs 3.3±1, P<.05), depth perception (4.6±0.7 vs 4.1±0.8 vs 3.2±1.0, P<.05), and border delineation (4.6±0.8 vs 4.1±1.0 vs 3.1±1.1, P<.05). The addition of the transparency mode to TI rendering significantly improves the diagnostic and clinical utility of 3D echocardiography and has the potential to markedly enhance echocardiographic guidance of cardiac structural interventions.

Void Space Surfaces to Convey Depth in Vessel Visualizations

To enhance depth perception and thus data comprehension, additional depth cues are often used in 3D visualizations of complex vascular structures. There is a variety of different approaches described in the literature, ranging from chromadepth color coding over depth of field to glyph-based encodings. Unfortunately, the majority of existing approaches suffers from the same problem: As these cues are directly applied to the geometry's surface, the display of additional information on the vessel wall, such as other modalities or derived attributes, is impaired. To overcome this limitation we propose Void Space Surfaces which utilizes empty space in between vessel branches to communicate depth and their relative positioning. This allows us to enhance the depth perception of vascular structures without interfering with the spatial data and potentially superimposed parameter information. With this article, we introduce Void Space Surfaces, describe their technical realization, and show their application to various vessel trees. Moreover, we report the outcome of two user studies which we have conducted in order to evaluate the perceptual impact of Void Space Surfaces compared to existing vessel visualization techniques and discuss expert feedback.

The effect of tints on distance stereoacuity under varying retinal illuminations

Background: Stereopsis is the accurate awareness of relative depth necessary for efficient hand–eye coordination and navigation. A popular brand of sunglasses claims to enhance depth perception. Aim: This study set out to investigate the effect of tinted lenses on distance stereoacuity under varying retinal illumination. Setting: This study was set at the Discipline of Optometry, University of KwaZulu-Natal. Methods: A pretest–post-test research design was used. Forty participants were recruited using convenience sampling. The Howard–Dolman apparatus was used to measure distance stereoacuity with different tints of a popular sporting brand under varying retinal illumination. The tinted lenses and their respective transmission values used included persimmon (61%), light grey (38%), G30 (30%) and black iridium (10%). The placebo comprised of a white lens (100% transmission). Habitual distance stereoacuity was measured with no lens as the control. Retinal illumination was varied with neutral density filters to simulate mesopic and scotopic conditions. The Friedman and paired t -tests were used to analyse the data. Results: The mean stereoacuity for each lens was significantly different across the three retinal illumination levels ( p < 0.05). A statistically significant difference ( p = 0.012) was found with only the light grey tint under scotopic conditions when compared to the habitual stereoacuity. However, clinically significant differences were noted with the persimmon, light grey and black iridium tints. Overall, poorer stereoacuity was noted in mesopic and scotopic conditions compared to photopic for all five lenses. Conclusion: Tinted lenses used had no statistically significant effect on distance stereoacuity but clinically significant changes were noted. However, the change in retinal illumination adversely affected distance stereoacuity.

How I do it: Flexible 3‐D endoscope for endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is technically challenging as a result of a lack of depth perception. The present article investigated the 3-D endoscope for carrying out ESD and translated the technique from bench to clinical use. In a preclinical porcine experiment, ESD using a 3-D endoscope was compared between an experienced and a novice endoscopist. All ESD were completed without perforation. Median operative time per surface area was significantly lower for the experienced endoscopist than for the novice (197.9 s/cm2 vs 434.7 s/cm2 ; P = 0.05). The second part was a prospective clinical experience to evaluate use of the 3-D endoscope for carrying out ESD. Ten patients received ESD using the 3-D endoscope. Four patients had gastric ESD, two had duodenal ESD and four had sigmoid and rectal ESD. There were no complications, whereas ESD failed in one patient who had gastric neoplasia at anastomosis. Mean operative time was 99.4 min, and operative time per surface area resection was 391 s/cm2 . The operating endoscopist did not complain of motion sickness, whereas the assistants had some dizziness upon prolonged ESD procedure. This study showed that carrying out ESD was safe and effective using a 3-D endoscope with an excellent 3-D view enhancing depth perception. Future study should be conducted to compare 3-D against 2-D endoscopes for ESD.