We present a novel method to accelerate the computation of the visibility function of the lighting equation, in dynamic scenes composed of rigid, non-penetrating objects. The main idea of the technique is to pre-compute for each object in the scene its associated four-dimensional field that describes the visibility in each direction for all positional samples on a sphere around the object, we c...

Volumetric effects such as beams of light through participating media are an important component in the appearance of the natural world. Many such effects can be faithfully modeled by a single scattering medium. In the presence of shadows, rendering these effects can be prohibitively expensive: current algorithms are based on ray marching, i.e., integrating the illumination scattered towards th...

Estimating visibility is one of the most important steps for multi-view reconstruction using volumetric scene representation. In this paper, we propose a simple approach to estimating visibility based on the current state of a scene which is implicitly represented as the zero level set of a function. Our method can determine the regions of a 3D space visible to several given viewpoints efficien...

Visibility of a simple stimulus is known to be determined not only by its physical contrast, but also by the configuration of surrounding stimuli. In this study, we investigated the surrounding modulation of foveal visibility of a blurred target. Subjects were instructed to respond to the gap orientation of a Gaussian-blurred Landolt ring presented at a fixation point with a surrounding stimulu...

Since radiance in a vacuum remains constant along rays, the radiance in a scene’s free space can be represented as a real function over the space of maximal segments. This space is four dimensional and organized by the visibility complex. To date only the 0-D and 1-D cells of the visibility complex have been constructed and implemented. In order to use this topological space to support radiance...

Nonuniform quantizers for just not visible reconstruction errors in an adaptive intra-/interframe DPCM scheme for componentcoded color television signals are presented, both for conventional DPCM and for noise-shaping DPCM. Noise feedback filters that minimize the visibility of reconstruction errors by spectral shaping are designed for Y, R-Y, and B-Y. A closed-form description of the “masking ...

Volume visualization has been widely used to depict complicated 3D structures in volume data sets. However, obtaining clear visualization of the features of interest in a volume is still a major challenge. The clarity of features depends on the transfer function, the viewpoint and the spatial distribution of features in the volume data set. In this paper, we propose visibility-weighted saliency...

Current codes in many countries require that the smoke layer be maintained a particular distance above the highest walking surface in an atrium. The smoke exhaust capacity to accomplish the required performance can be extraordinary, especially in a tall atrium with the upper floors open to the atrium. The effect of exposure to smoke is a function of the magnitude of the smoke signature, e.g. co...