7 research outputs found
Outdoor 3D illumination in real time environments: A novel approach
Comprehensive enlightenment is one of the fundamental components that virtualize the real environment. Accordingly, sky shading is one of the important components considered in the virtualization process. This research introduces the Dobashi method of sky luminance; additionally, Radiosity Caster Culling is applied to the virtual objects as the second thought for outside illumination. Pre-Computed Radiance Transfer is connected to ascertain the division of patches. Moreover, for real sky shading, the Perez model is utilized. By pre-ascertaining sky shading vitality and outside light, the vitality of the entire open air is figured ahead of time. The open air vitality is shared on virtual articles to make the situations more practical. Commercial videos and cartoon creators could utilize the strategy to produce real outside situations. © 2017
LivePhantom: Retrieving Virtual World Light Data to Real Environments.
To achieve realistic Augmented Reality (AR), shadows play an important role in creating a 3D impression of a scene. Casting virtual shadows on real and virtual objects is one of the topics of research being conducted in this area. In this paper, we propose a new method for creating complex AR indoor scenes using real time depth detection to exert virtual shadows on virtual and real environments. A Kinect camera was used to produce a depth map for the physical scene mixing into a single real-time transparent tacit surface. Once this is created, the camera's position can be tracked from the reconstructed 3D scene. Real objects are represented by virtual object phantoms in the AR scene enabling users holding a webcam and a standard Kinect camera to capture and reconstruct environments simultaneously. The tracking capability of the algorithm is shown and the findings are assessed drawing upon qualitative and quantitative methods making comparisons with previous AR phantom generation applications. The results demonstrate the robustness of the technique for realistic indoor rendering in AR systems
3D URBAN GEOVISUALIZATION: IN SITU AUGMENTED AND MIXED REALITY EXPERIMENTS
In this paper, we assume that augmented reality (AR) and mixed reality (MR) are relevant contexts for 3D urban geovisualization, especially in order to support the design of the urban spaces. We propose to design an in situ MR application, that could be helpful for urban designers, providing tools to interactively remove or replace buildings in situ. This use case requires advances regarding existing geovisualization methods. We highlight the need to adapt and extend existing 3D geovisualization pipelines, in order to adjust the specific requirements for AR/MR applications, in particular for data rendering and interaction. In order to reach this goal, we focus on and implement four elementary in situ and ex situ AR/MR experiments: each type of these AR/MR experiments helps to consider and specify a specific subproblem, i.e. scale modification, pose estimation, matching between scene and urban project realism, and the mix of real and virtual elements through portals, while proposing occlusion handling, rendering and interaction techniques to solve them
Real-time Illumination and Visual Coherence for Photorealistic Augmented/Mixed Reality
A realistically inserted virtual object in the real-time physical environment is a desirable feature in augmented reality (AR) applications and mixed reality (MR) in general. This problem is considered a vital research area in computer graphics, a field that is experiencing ongoing discovery. The algorithms and methods used to obtain dynamic and real-time illumination measurement, estimating, and rendering of augmented reality scenes are utilized in many applications to achieve a realistic perception by humans. We cannot deny the powerful impact of the continuous development of computer vision and machine learning techniques accompanied by the original computer graphics and image processing methods to provide a significant range of novel AR/MR techniques. These techniques include methods for light source acquisition through image-based lighting or sampling, registering and estimating the lighting conditions, and composition of global illumination. In this review, we discussed the pipeline stages with the details elaborated about the methods and techniques that contributed to the development of providing a photo-realistic rendering, visual coherence, and interactive real-time illumination results in AR/MR
LightSkin: Globale Echtzeitbeleuchtung für Virtual und Augmented Reality
In nature, each interaction of light is bound to a global context. Thus,
each observable natural light phenomenon is the result of global
illumination. It is based on manifold laws of absorption, reflection, and
refraction, which are mostly too complex to simulate given the real-time
constraints of interactive applications. Therefore, many interactive
applications do not support the simulation of those global illumination
phenomena yet, which results in unrealistic and synthetic-looking
renderings. This unrealistic rendering becomes especially a problem in the
context of virtual reality and augmented reality applications, where the
user should experience the simulation as realistic as possible. In this
thesis we present a novel approach called LightSkin that calculates global
illumination phenomena in real-time. The approach was especially developed
for virtual reality and augmented reality applications satisfying several
constraints coming along with those applications. As part of the approach
we introduce a novel interpolation scheme, which is capable to calculate
realistic indirect illumination results based on a few number of supporting
points, distributed on model surfaces. Each supporting point creates its
own proxy light sources, which are used to represent the whole indirect
illumination for this point in a compact manner. These proxy light sources
are then linearly interpolated to obtain dense results for the entire
visible scene. Due to an efficient implementation on GPU, the method is
very fast supporting complex and dynamic scenes. Based on the approach, it
is possible to simulate diffuse and glossy indirect reflections, soft
shadows, and multiple subsurface scattering phenomena without neglecting
filigree surface details. Furthermore, the method can be adapted to
augmented reality applications providing mutual global illumination effects
between dynamic real and virtual objects using an active RGB-D sensor
device. In contrast to existing interactive global illumination approaches,
our approach supports all kinds of animations, handling them more
efficient, not requiring extra calculations or leading to disturbing
temporal artifacts. This thesis contains all information needed to
understand, implement, and evaluate the novel LightSkin approach and also
provides a comprehensive overview of the related field of research.In der Natur ist jede Interaktion des Lichts mit Materie in einen globalen
Kontext eingebunden, weswegen alle natürlichen Beleuchtungsphänomene in
unserer Umwelt das Resultat globaler Beleuchtung sind. Diese basiert auf
der Anwendung mannigfaltiger Absorptions-, Reflexions- und
Brechungsgesetze, deren Simulation so komplex ist, dass interaktive
Anwendungen diese nicht in wenigen Millisekunden berechnen können. Deshalb
wurde bisher in vielen interaktiven Systemen auf die Abbildung von solchen
globalen Beleuchtungsphänomenen verzichtet, was jedoch zu einer
unrealistischen und synthetisch-wirkenden Darstellung führte. Diese
unrealistische Darstellung ist besonders für die Anwendungsfelder Virtual
Reality und Augmented Reality, bei denen der Nutzer eine möglichst
realitätsnahe Simulation erfahren soll, ein gewichtiger Nachteil. In dieser
Arbeit wird das LightSkin-Verfahren vorgestellt, das es erlaubt, globale
Beleuchtungsphänomene in einer Echtzeitanwendung darzustellen. Das
Verfahren wurde speziell für die Anwendungsfelder Virtual Reality und
Augmented Reality entwickelt und erfüllt spezifische Anforderungen, die
diese an eine Echtzeitanwendung stellen. Bei dem Verfahren wird das
indirekte Licht durch eine geringe Anzahl von Punktlichtquellen
(Proxy-Lichtquellen) repräsentiert, die für eine lose Menge von
Oberflächenpunkten (Caches) berechnet und anschließend über die komplette
sichtbare Szene interpoliert werden. Diese neue Form der Repräsentation der
indirekten Beleuchtung erlaubt eine effiziente Berechnung von diffusen und
glänzenden indirekten Reflexionen, die Abbildung von weichen Schatten und
die Simulation von Multiple-Subsurface-Scattering-Effekten in Echtzeit für
komplexe und voll dynamische Szenen. Ferner wird gezeigt, wie das Verfahren
modifiziert werden kann, um globale Lichtwechselwirkungen zwischen realen
und virtuellen Objekten in einer Augmented-Reality-Anwendung zu simulieren.
Im Gegensatz zu den meisten existierenden Echtzeitverfahren zur Simulation
von globalen Beleuchtungseffekten benötigt der hier vorgestellte Ansatz
keine aufwändigen zusätzlichen Berechnungen bei Animationen und erzeugt
darüber hinaus für diese keine visuellen Artefakte. Diese Arbeit enthält
alle Informationen, die zum Verständnis, zur Implementierung und zur
Evaluation des LightSkin-Verfahrens benötigt werden und gibt darüber hinaus
einen umfassenden Über- blick über das Forschungsfeld