Matches in SemOpenAlex for { <https://semopenalex.org/work/W83553142> ?p ?o ?g. }
Showing items 1 to 65 of
65
with 100 items per page.
- W83553142 endingPage "156" @default.
- W83553142 startingPage "156" @default.
- W83553142 abstract "Light interacts with the world around us in complex ways. These interactions can broadly be classified as direct illumination — when a scene point is illuminated directly by the light source, or indirect illumination — when a scene point receives light that is reflected, refracted or scattered off other scene elements. Several computer vision techniques make the unrealistic assumption that scenes receive only direct illumination. In many real-world scenarios, such as indoors, underground caves, underwater, foggy conditions and for objects made of translucent materials like human tissue, fruits and flowers, the amount of indirect illumination is significant, often more than the direct illumination. In these scenarios, vision techniques that do not account for the indirect illumination result in strong and systematic errors in the recovered scene properties. The above stated assumption is made because computational models for indirect illumination (also called global illumination or global light transport) are complex, even for relatively simple scenes. The goal of this thesis is to build simple, tractable models of global light transport, which can be used for a variety of scene recovery and rendering applications. This thesis has three contributions. First, recovering scene geometry and appearance despite the presence of global light transport. We show that two different classes of shape recovery techniques - structured light triangulation and shape from projector defocus - can be made robust to the effects of global light transport. We demonstrate our approaches on scenes with complex shapes and optically challenging materials. We then investigate the problem of recovering scene appearance in the presence of common poor visibility scenarios, such as murky water, bad weather, dust and smoke. Computer vision systems deployed in such conditions suffer due to scattering and attenuation of light. We show that by controlling the incident illumination, loss of image contrast due to scattering can be significantly reduced. Our framework can be used for improving visibility in a variety of outdoor applications, such as designing headlights for vehicles, both terrestrial and underwater. Global light transport is not always noise. In numerous scenarios, measuring global light transport can actually provide useful information about the scene. The second contribution is to recover material and scene properties by measuring global light transport. We present a simple device and technique for robustly measuring the volumetric scattering properties of a broad class of participating media. We have constructed a data-set of the scattering properties, which can be immediately used by the computer graphics community to render realistic images. Next, we model the effects of defocused illumination on the process of measuring global light transport in general scenes. Modeling the effects of defocus is important because projectors, having limited depth-of-field, are increasingly being used as programmable illumination in vision applications. With our techniques, we can separate the direct and global components of light transport for scenes whose depth-ranges are significantly greater than the depth of field of projectors (< 0.3m). The third contribution of this thesis is fast rendering of dynamic and non-homogenous volumetric media, such as fog, smoke, and dust. Rendering such media requires simulating the fluid properties (density and velocity fields) and rendering volumetric scattering effects. Unfortunately, fluid simulation and volumetric rendering have always been treated as two disparate problems in computer graphics, making it hard to leverage the advances made in both fields together. In particular, reduced space methods have been developed separately for both fields, which exploit the observation that the associated fields (density, velocity and intensity) can be faithfully represented with a relatively small number of parameters. We develop a unified reduced space framework for both fluid simulation and volumetric rendering. Since both fluid simulation and volumetric rendering are done in a reduced space, our technique achieves computational speed-ups of one to three orders of magnitude over traditional spatial domain methods. We demonstrate complex visual effects resulting from volumetric scattering in dynamic and non-homogenous media, including fluid simulation effects such as particles inserted in turbulent wind-fields." @default.
- W83553142 created "2016-06-24" @default.
- W83553142 creator A5029497982 @default.
- W83553142 creator A5074353153 @default.
- W83553142 date "2010-01-01" @default.
- W83553142 modified "2023-09-24" @default.
- W83553142 title "Scene recovery and rendering techniques under global light transport" @default.
- W83553142 hasPublicationYear "2010" @default.
- W83553142 type Work @default.
- W83553142 sameAs 83553142 @default.
- W83553142 citedByCount "0" @default.
- W83553142 crossrefType "journal-article" @default.
- W83553142 hasAuthorship W83553142A5029497982 @default.
- W83553142 hasAuthorship W83553142A5074353153 @default.
- W83553142 hasConcept C110541219 @default.
- W83553142 hasConcept C121684516 @default.
- W83553142 hasConcept C154945302 @default.
- W83553142 hasConcept C205711294 @default.
- W83553142 hasConcept C2524010 @default.
- W83553142 hasConcept C2776865275 @default.
- W83553142 hasConcept C28719098 @default.
- W83553142 hasConcept C31972630 @default.
- W83553142 hasConcept C33923547 @default.
- W83553142 hasConcept C41008148 @default.
- W83553142 hasConcept C89720835 @default.
- W83553142 hasConceptScore W83553142C110541219 @default.
- W83553142 hasConceptScore W83553142C121684516 @default.
- W83553142 hasConceptScore W83553142C154945302 @default.
- W83553142 hasConceptScore W83553142C205711294 @default.
- W83553142 hasConceptScore W83553142C2524010 @default.
- W83553142 hasConceptScore W83553142C2776865275 @default.
- W83553142 hasConceptScore W83553142C28719098 @default.
- W83553142 hasConceptScore W83553142C31972630 @default.
- W83553142 hasConceptScore W83553142C33923547 @default.
- W83553142 hasConceptScore W83553142C41008148 @default.
- W83553142 hasConceptScore W83553142C89720835 @default.
- W83553142 hasLocation W835531421 @default.
- W83553142 hasOpenAccess W83553142 @default.
- W83553142 hasPrimaryLocation W835531421 @default.
- W83553142 hasRelatedWork W1510300251 @default.
- W83553142 hasRelatedWork W1588611743 @default.
- W83553142 hasRelatedWork W177330105 @default.
- W83553142 hasRelatedWork W1973042181 @default.
- W83553142 hasRelatedWork W1987212881 @default.
- W83553142 hasRelatedWork W1988716435 @default.
- W83553142 hasRelatedWork W2007916569 @default.
- W83553142 hasRelatedWork W2013488655 @default.
- W83553142 hasRelatedWork W2081579113 @default.
- W83553142 hasRelatedWork W2091001178 @default.
- W83553142 hasRelatedWork W2093560942 @default.
- W83553142 hasRelatedWork W2101591917 @default.
- W83553142 hasRelatedWork W2128826822 @default.
- W83553142 hasRelatedWork W2248901057 @default.
- W83553142 hasRelatedWork W2408457912 @default.
- W83553142 hasRelatedWork W3113005628 @default.
- W83553142 hasRelatedWork W3208058133 @default.
- W83553142 hasRelatedWork W43948910 @default.
- W83553142 hasRelatedWork W641869877 @default.
- W83553142 hasRelatedWork W2559764398 @default.
- W83553142 isParatext "false" @default.
- W83553142 isRetracted "false" @default.
- W83553142 magId "83553142" @default.
- W83553142 workType "article" @default.