Tibor Balogh

The HoloVizio system

We present the HoloVizio system design and give an overview about Holografikas approach to the 3D displaying. The patented HoloVizio technology uses a specially arranged array of optical modules and a holographic screen. Each point of the holographic screen emits light beams of different color and intensity to the various directions. The light beams generated in the optical modules hit the screen points in various angles and the holographic screen makes the necessary optical transformation to compose these beams into a perfectly continuous 3D view. With proper software control, light beams leaving the pixels propagate in multiple directions, as if they were emitted from the points of 3D objects at fixed spatial locations. We show that the direction selective light emission is a general requirement for every 3D systems and provide quantitative data on the FOV, on the angular resolution, determining field of depth of the displays, affecting the total number of light beams necessary for high-end 3D displaying. We present the results with the 10 Mpixel desktop display and the 50Mpixel large-scale system. We cover the real-time control issues at high pixel-count systems with the HoloVizio software environment and describe concrete 3D applications developed in the frame of European projects.

A Large Scale Interactive Holographic Display

Our work focuses on the development of interactive multi-user holographic displays that allow freely moving naked eye participants to share a three dimensional scene with fully continuous, observer independent, parallax. Our approach is based on a scalable design that exploits a specially arranged array of projectors and a holographic screen. The feasibility of such an approach has already been demonstrated with a working hardware and software 7.4M pixel prototype driven at 10-15Hz by two DVI streams. In this short contribution, we illustrate our progress, presenting a 50M pixel display prototype driven by a dedicated cluster hosting multiple consumer level graphic cards.

A Scalable Hardware and Software System for the Holographic Display of Interactive Graphics Applications

We present a scalable holographic system design targeting multi-user interactive computer graphics applications. The display uses a specially arranged array of micro-displays and a holographic screen. Each point of the holographic screen emits light beams of different color and intensity to the various directions, in a controlled manner. The light beams are generated through a light modulation system arranged in a specic geometry and the holographic screen makes the necessary optical transformation to compose these beams into a perfectly continuous 3D view. With proper software control, the light beams leaving the various pixels can be made to propagate in multiple directions, as if they were emitted from physical objects at xed spatial locations. The display is driven by DVI streams generated by multiple consumer level graphics boards and decoded in real-time by image processing units that feed the optical modules at high refresh rates. An OpenGL compliant library running on a client PC redenes the OpenGL behavior to multicast graphics commands to server PCs, where they are re-interpreted for implementing holographic rendering. The feasibility of the approach has been successfully evaluated with a working hardware and software 7.4M pixel prototype driven at 10-15Hz by three DVI streams.

Holovizio 3D Display System

We present the HoloVizio system design and give an overview of Holografikas approach to the 3D displaying. The patented HoloVizio technology uses a specially arranged array of optical modules and a holographic screen. Each point of the holographic screen emits light beams of different color and intensity to various directions. With proper software control, light beams leaving the pixels propagate in multiple directions, as if they were emitted from the points of 3D objects at fixed spatial locations. We show that the direction selective light emission is a general requirement for every 3D systems and the advantages of light field reconstruction over the multiview approach. We describe the 10 Mpixel desktop display and the 50 Mpixel large-scale system. We cover the real-time control issues at high pixel-count systems with the HoloVizio software environment and describe concrete 3D applications developed in the frame of European projects.

Freehand interaction with large-scale 3D map data

In this paper, we present our method and apparatus to visualize and interact with large-scale 3D map data on a 3D light-field display in real time. 3D map data are streamed over Internet to the display in real-time based on request sent by the application. On the user side, data is processed and visualized on a large-scale 3D light field display. We present a method to efficiently interact with the visualized 3D map using freehand gestures. We use a Leap Motion sensor that supports sufficient refresh rate for our current application and is able to accurately track and acquire information on the user hand position. This information is further processed to support natural and fast interaction. We have also developed a method to automatically adjust the maps plane to the screen plane of the display. The visualization and interaction method is scalable and allows the exploration of large-scale 3D maps down to the street level.

An interactive multi-user holographic environment

We present an interactive multi-user holographic environment that allows freely moving naked eye participants to share a large 3D scene with fully continuous, observer independent, parallax.

Light-field video coding using geometry-based disparity compensation

One of the main challenges in 3D light-field imaging approaches lies in the massive amount of visual information involved in providing 3D content with sufficient resolution. Consequently, adequate coding tools are essential for efficient transmission and storage of this type of content. In this context, this paper presents and evaluates two coding solutions based on the High Efficiency Video Coding (HEVC) scheme and for efficient compression of the 3D light-field content. These two coding schemes aim to exploit the 3D geometry-based disparity information in the 3D light field content and replace the block-based disparity estimation. In the first scheme, the disparity map of each view is used to directly derive the vectors for compensation, and in the second scheme these disparity vectors (for all views) are calculated (for non-occluded areas) from the disparity map of the base view. A comparative study of these proposed coding schemes is performed and future research directions are also discussed.

Holographic and action capture techniques

We present an integrated 3D capturing, visualization and user interaction system composed of a computer vision based 3D capturing device, a scene composer and a large scale holographic display. The system performs in real-time and provides the facilities required for capturing realistic human 3D body models, inserting the human representations inside virtual scenarios, detecting 3D interactions between the body models and the virtual objects present in the scene and visualizing the resulting 3D performance on a true 3D holographic display.

Viva la resolution: the perceivable differences between image resolutions for light field displays

As 3D display technologies are becoming more and more common in commercial, everyday usage, a special type of 3D known as projection-based light field displays is emerging as well. While holding many key characteristics such as field of view or angular resolution, traditional image resolution also plays a major role in the overall determination of user experience, similarly to 2D displays. The paper investigates the perceivable differences between display resolutions, and presents the acceptability of resolution degradation should it be visible. A total of 20 test participants provided subjective assessment in a series of pair comparisons between 5 resolutions for various stimuli. Beyond mean scores, the results are presented in terms of score distribution in this analysis, separately for each and every stimulus.

Natural 3D content on glasses-free light-field 3D cinema

This paper presents a complete framework for capturing, processing and displaying the free viewpoint video on a large scale immersive light-field display. We present a combined hardware-software solution to visualize free viewpoint 3D video on a cinema-sized screen. The new glasses-free 3D projection technology can support larger audience than the existing autostereoscopic displays. We introduce and describe our new display system including optical and mechanical design considerations, the capturing system and render cluster for producing the 3D content, and the various software modules driving the system. The indigenous display is first of its kind, equipped with front-projection light-field HoloVizio technology, controlling up to 63 MP. It has all the advantages of previous light-field displays and in addition, allows a more flexible arrangement with a larger screen size, matching cinema or meeting room geometries, yet simpler to set-up. The software system makes it possible to show 3D applications in real-time, besides the natural content captured from dense camera arrangements as well as from sparse cameras covering a wider baseline. Our software system on the GPU accelerated render cluster, can also visualize pre-recorded Multi-view Video plus Depth (MVD4) videos on this light-field glasses-free cinema system, interpolating and extrapolating missing views.