Image-based rendering techniques have proven to be a powerful
alternative to traditional polygon-based computer graphics.
This thesis presents a novel light field rendering technique
which performs per-pixel depth correction of rays for
high-quality light field reconstruction. The technique stores
combined RGB and depth values in a parabolic 2D texture for
every light field sample being acquired at discrete positions
in a uniform spherical setup. Image synthesis is implemented on
the graphics processing unit within a customized fragment program which extracts the
correct image information from adjacent cameras for each
fragment by applying per-pixel depth correction of rays.
This dissertation demonstrates that the presented image-based
rendering technique provides a significant improvement compared
to previous approaches. Two different rendering implementations
are explained which make use of the uniform parametrization to
minimize disparity problems and ensure full six degrees of
freedom for virtual view synthesis. While one rendering
algorithm implements an iterative refinement approach for
rendering light fields with per-pixel depth correction, the
other approach employs a raycaster which provides superior
rendering quality at moderate frame rates.
Graphics processing unit based per-fragment depth correction of rays, used in both
implementations, helps reducing ghosting artifacts to a non
noticeable amount and provides a rendering technique that
performs without exhaustive pre-processing for 3D object
reconstruction.
The presented light field techniques open up for the
implementation of efficient and flexible rendering approaches.
This work presents an efficient level of detail rendering
approach for light fields and introduces a flexible rendering
technique for remote access to light field representation in a
web-based client-server application.
For the acquisition of spherical light fields with per-pixel
depth a new acquisition system is presented which makes use of
recent advances in 3D sensor technology to acquire combined RGB
and depth images directly.