Chromatic shadows for improved perception

Veronika Šoltészová*, Daniel Patel, Ivan Viola

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

29 Scopus citations

Abstract

Soft shadows are effective depth and shape cues. However, traditional shadowing algorithms decrease the luminance in shadow areas. The features in shadow become dark and thus shadowing causes information hiding. For this reason, in shadowed areas, medical illustrators decrease the luminance less and compensate the lower luminance range by adding color, i.e., by introducing a chromatic component. This paper presents a novel technique which enables an interactive setup of an illustrative shadow representation for preventing overdarkening of important structures. We introduce a scalar attribute for every voxel denoted as shadowiness and propose a shadow transfer function that maps the shadowiness to a color and a blend factor. Typically, the blend factor increases linearly with the shadowiness. We then let the original object color blend with the shadow color according to the blend factor. We suggest a specific shadow transfer function, designed together with a medical illustrator which shifts the shadow color towards blue. This shadow transfer function is quantitatively evaluated with respect to relative depth and surface perception.

Original languageEnglish (US)
Title of host publicationProceedings - NPAR 2011
Subtitle of host publicationACM SIGGRAPH / Eurographics Symposium on Non-Photorealistic Animation and Rendering
Pages105-115
Number of pages11
DOIs
StatePublished - Dec 1 2011
Event9th International Symposium on Non-Photorealistic Animation and Rendering, NPAR 2011, Co-located with ACM SIGGRAPH 2011 - Vancouver, BC, Canada
Duration: Aug 5 2011Aug 7 2011

Publication series

NameNPAR Symposium on Non-Photorealistic Animation and Rendering

Conference

Conference9th International Symposium on Non-Photorealistic Animation and Rendering, NPAR 2011, Co-located with ACM SIGGRAPH 2011
CountryCanada
CityVancouver, BC
Period08/5/1108/7/11

Keywords

  • Illustration
  • Shadow
  • Shape and depth perception

ASJC Scopus subject areas

  • Applied Mathematics
  • Computer Graphics and Computer-Aided Design
  • Computer Science Applications
  • Modeling and Simulation

Fingerprint

Dive into the research topics of 'Chromatic shadows for improved perception'. Together they form a unique fingerprint.

Cite this