Occlusion in collaborative augmented environments

Abstract

Augmented environments superimpose computer enhancements on the real world. Such augmented environments are well suited for collaboration of multiple users. To improve the quality and consistency of the augmentation the occlusion of real objects by computergenerated objects and vice versa has to be implemented. We present methods how this can be done for a tracked user's body and other real objects and how irritating artifacts due to misalignments can be reduced. Our method is based on simulating the occlusion of virtual objects by a representation of the user modeled as kinematic chains of articulated solids. Registration and modeling errors of this model are being reduced by smoothing the border between virtual world and occluding real object. An implementation in our augmented environment and the resulting improvements are presented.

Occlusion shadows: using projected light to generate realistic occlusion effects for view-dependent optical see-through displays

“…Surfaces that are aligned roughly parallel to the projector's image plane (e.g., the base in figures 1,3,4) allow us to achieve sub-pixel precision since the fiducials can be referenced exactly in the frame-buffer. Surfaces that are oriented more perpendicular to the image plane (e.g., skull in figure 7) still produce an average precision of 1-3 pixels 6 . In addition, an object-based or image-based blurring can be applied to reduce the visual effects caused by slight registration errors, as described by Fuhrmann et al [6].…”

“…Surfaces that are oriented more perpendicular to the image plane (e.g., skull in figure 7) still produce an average precision of 1-3 pixels 6 . In addition, an object-based or image-based blurring can be applied to reduce the visual effects caused by slight registration errors, as described by Fuhrmann et al [6]. Similar effects can be achieved by simply defocusing the projectors' optics -with no computational cost involved.…”

Desenvolvimento de um sistema para demonstração da projeção de Monge utilizando realidade aumentada

“…Nesse instituto foi desenvolvido o sistema pioneiro para ensino utilizando a realidade aumentada denominado Studierstube [14]. Questões técnicas de oclusão em ambientes colaborativos de realidade aumentada já eram abordadas no final da década de 1990 [15] nesse instituto, bem como nos Estados Unidos, no Laboratório de Tecnologias de Interfaces Humanas [16].…”

Augmented Reality Tracking Techniques: A Systematic Literature Review Protocol

“…The virtual objects and real world environment are required to be of same Illumination [10,11]. Another issue is occlusion, that is a process to determine which surface or its parts are not visible from a certain view-point [12,13] The paper reports our study plan in the form of SLR protocol. This paper presents the design of a first of its kind study in augmented reality tracking techniques.…”