Consistent Illumination within Augmented Environments

To achieve a consistent lighting situation between real and virtual environments is important for convincing augmented reality (AR) applications.
A rich pallet of algorithms and techniques have been developed that match illumination for video- or image-based augmented reality. However, very little work has been done in this area for optical see-through AR. We believe that the optical see-through concept is currently the most advanced technological approach to provide an acceptable level of realism and interactivity.
Methods have been developed which create a consistent illumination between real and virtual components within an optical see-through environment -- such as the Virtual Showcase. Combinations of video projectors and cameras are applied to capture reflectance information from diffuse real objects and to illuminate them under new synthetic lighting conditions. For diffuse objects, the capturing process can also benefit from hardware acceleration -- supporting dynamic update rates. To handle indirect lighting effects (like color bleeding) an off-line radiosity procedure is outlined that consists of multiple rendering passes. For direct lighting effects (such as simple shading, shadows and reflections) hardware accelerated techniques are described which allow to achieve interactive frame rates. The reflectance information is used in addition to solve a main problem of a previously introduced technique which creates consistent occlusion effects for multiple users within such environments.
Bimber, O.,Grundhöfer, A., Wetzstein, G., and Knödel, S.
Consistent Illumination within Optical See-Through Augmented Environments
In proceedings of International Symposium on Mixed and Augmented Reality(ISMAR'03), pp. 198-207, 2003

Category:

Science & Technology

Tags:

• computer
• augmented
• reality
• electronics
• environment