The key performance indicators of projection-based light field visualization

2021 International Conference on 3D Immersion (IC3D)

Guindy

Balogh

et al. 2021

Self Cite

As the research efforts and development processes behind light field visualization technologies advance, potential novel use cases emerge. These contexts of light field display utilization fundamentally depend on the distance of observation, due to the sheer technological nature of such glasses-free 3D systems. Yet, at the time of this paper, the number of works in the scientific literature that address viewing distance is rather limited, focusing solely on 3D visual experience based on angular density. Thus far, the personal preference of observers regarding viewing distance has not been considered by studies. Furthermore, the upcoming standardization efforts also necessitate research on the topic in order to coherently unify the methodologies of subjective tests. In this paper, we investigate the perceptually-supported and the subjectively-preferred viewing distance of light field visualization. We carried out a series of tests on multiple projection-based light field displays to study these distances, with the separate involvement of experts and regular test participants.

Section: Related Workmentioning

confidence: 99%

The Perceptually-Supported and the Subjectively-Preferred Viewing Distance of Projection-Based Light Field Displays

2021 International Conference on 3D Immersion (IC3D)

Guindy

Balogh

et al. 2021

Self Cite

“…Our earlier works on the quality of light field visualization address spatial resolution, 1 angular resolution 2 and FOV, 3 and also review the relevant KPIs. 4 While such characteristics of content and display are directly studied -e.g., by the research efforts of Kovacs et al 5,6 -yet the majority of the scientific literature on light field visualization approaches the topic of quality degradation via compression. Kovacs et al 7 investigated H.264/MVC, Adhikarla et al, 8 Ahar et al, 9 Bakir et al, 10 Paudyal et al, 11 Perra et al, 12 Recio et al, 13 Shi et al 14 and Tian et al 15 involved H.265/HEVC.…”

Section: Related Workmentioning

confidence: 99%

On the use-case-specific quality degradations of light-field visualization

Novel Optical Systems, Methods, and Applications XXIV

Tamboli²,

Balogh

et al. 2021

Self Cite

Through the immense scientific efforts of the past two decades, light field visualization is now emerging in the industry, and commercial, everyday use cases are also expected to benefit from this glasses-free true 3D technology in the near future. While the technology itself may enable a natural 3D experience, there are, in fact, certain situations where visualization quality is not optimal. This can be due to the attributes of light field capture, transmission, compression, and numerous other factors that may degrade the perceived quality. However, the impact of such degraded quality fundamentally depends on the actual use case at hand. For example, while a specific amount of generic blur or disruption in the smoothness of the continuous horizontal and/or vertical parallax may cause minor inconveniences in a given use case, it may result in significant errors and substantial issues in another. In this paper, we analyze the use-case-specific quality degradations of light field visualization. Each and every key performance indicator of light field visualization quality is addressed, and their effects are separately studied in the context of each use case. Display and content parameters, such as angular resolution, are examined on the level of individual and combined thresholds. The investigated use cases cover industrial, medical, commercial, educational, cultural and communicational scenarios. Therefore, both active and passive utilizations are considered, and a special emphasis on task performance is included in this paper.

“…This distance is solely influenced by the angular resolution of the display -another important key performance indicator (KPI) of light field visualization. 1 In case of 2D displays, the recommended viewing distance is commonly based on the height of the screen, denoted by H. In the scope of this paper, H is not considered, since the 2D-equivalent spatial resolution is not as vital to the overall perceived visualization quality of light field displays as angular resolution is. 2 The rule of thumb within the scientific community is that in order to achieve 3D sensation during the observation of light field content, the two eyes of the viewer must be addressed by two distinct light rays, coming from the same point on the screen of the display.…”

Section: Introductionmentioning

confidence: 99%

Recommendations on the viewing distance of light field displays

Digital Optical Technologies 2021

Barsi

Tamboli³

et al. 2021

Self Cite

Light field visualization is an emerging 3D technology that does not rely on viewing devices, such as special glasses. Without the need for such additional devices, multiple users may simultaneously enjoy the glasses-free 3D experience from a virtually infinite number of viewing positions, as the motion parallax is continuous and smooth. Although this immensely valuable property of light field displays does enable a great deal of viewing freedom, the proper perception of the visualized content still depends on the position of the observer. Position in this context determines the distance and the angle of the observer, with respect to the screen of the display. The validity of the latter is relatively straightforward to assess: if the observer is viewing the screen from inside the angle set by the field of view of the display, then the content shall be seen from its perceptually correct angle. However, the fundamental issue with the underinvestigated topic of viewing distance is that light field visualization may lose its 3D nature if viewed from a far-away position. This is due to the fact that in such a case, a single point of the screen may emit identical rays of light towards the two pupils of the observer. Therefore, the deficiency of disparity, the lack of distinct rays may lead to a 2D visual experience, nullifying the core scientific contribution of this technology. Of course, moving sideways in front of a horizontal-only-parallax display may, in fact, induce a 3D experience via the natural sense of parallax, but it should be applicable regardless of movement. Needless to say, in a multitude of professional environments, the users of such displays are not expected to be highly mobile during the work-related utilization of the technology. However, at the time of this paper, merely a few publications of the scientific literature address the topic of viewing distance, and standardization efforts are still in a rather early phase. Summa summarum, light field displays need clear guidelines with regard to viewing distance, which may benefit both the manufacturers and the users. Such guiding principles may make development and production more cost-efficient and user-oriented, and may contribute to the increased efficiency of usage-focused display design. In this paper, we provide a series of recommendations on the viewing distance of light field displays. The displays are separately analyzed within the context of their own use cases, taking into account the key performance indicators of both the apparatus and the visualized content, the various environmental conditions, as well as the relevant use-case-scenario-specific necessities and the professional requirements. The investigated use cases include medical imaging, telepresence, resource exploration, prototype review, training and education, gaming, digital signage, cinematography, cultural heritage exhibition, air traffic control and driver assistance systems.