An Image-Based Approach to Three-Dimensional Computer Graphics


Ph.D. Dissertation, Leonard McMillan (under the direction of Gary Bishop)
University of North Carolina, April 1997.
(UNC-CH Computer Science Technical Report TR97-013).

Abstract

The conventional approach to three-dimensional computer graphics produces images from geometric scene descriptions by simulating the interaction of light with matter. My research explores an alternative approach that replaces the geometric scene description with perspective images and replaces the simulation process with data interpolation.

I derive an image-warping equation that maps the visible points in a reference image to their correct positions in any desired view. This mapping from reference image to desired image is determined by the center-of-projection and pinhole-camera model of the two images and by a generalized disparity value associated with each point in the reference image. This generalized disparity value, which represents the structure of the scene, can be determined from point correspondences between multiple reference images.

The image-warping equation alone is insufficient to synthesize desired images because multiple reference-image points may map to a single point. I derive a new visibility algorithm that determines a drawing order for the image warp. This algorithm results in correct visibility for the desired image independent of the reference image's contents.

The utility of the image-based approach can be enhanced with a more general pinhole-camera model. I provide several generalizations of the warping equation's pinhole-camera model and discuss how to build an image-based representation when information about the reference image's center-of-projection and camera model is unavailable.