Real-Time Image Warping for Curved Mirror Displays

Displays which require a non-linear pre-distortion to present undistorted gfx on non-planar surfaces, or to neutralize optical distortion usually apply multi-pass rendering techniques. Projective textures or uniform grids are used to deform the image generated during the first pass before it is displayed as a texture map during the final pass. However, these approaches do not consider the error that is generated from a piecewise linear texture interpolation to adapt the underlying geometry.
Curved mirror displays, for instance, that stereoscopically produce three-dimensional gfx generally don't pre-distort the graphics before they are displayed. Yet, some systems apply additional optics (such as lenses) to stretch or undistort the reflected image. But these devices constrain the observer to a single point of view or to very restricted viewing zones. For the Virtual Showcase mirror display, however, a view-dependent rendering is required to support freely moving observers. The existing image warping algorithms for curved Virtual Showcases predistort a uniform image grid and consequently do not consider the local error that is generated from a piecewise linear texture interpolation. These algorithms can only produce an acceptable image quality within a significantly large amount of rendering time.
The algorithm that is presented improves the uniform image warping techniques for curved Virtual Showcases by defining an appropriate error metric and implementing a quadtree-based selective refinement method that generates adapted local levels of detail. It approaches to produce a predefined image quality within a minimum amount of rendering time. While display specific details of our algorithm are explained based on the Virtual Showcase display, its general functionality is valid for other non-linear displays -such as for curved projection-based systems.
Bimber, O., Fröhlich, B., Schmalstieg, D., and Encarnação, L.M.
Real-Time View-Dependent Image Warping to correct Non-Linear Distortion for Curved Virtual Showcase Displays
In Computers and Graphics - The international Journal of Systems and Applications in Computer Graphics, vol. 27, no. 4, pp. 512-528, 2003

Category:

Science & Technology

Tags:

• computer
• augmented
• reality
• electronics
• environment

[dracentsparkle]

thanks for the kind sharing*

[Mcoyxx]

an image distorting mirror keeps the owner constantly unhappy!..quote me

[vincimanu]

warping reality cool

[nowintheaters]

wow cool

[crustea]

Very clever ! Dali would love that :)