Assumed Lighting Direction in the Interpretation of Cast Shadows

Tomomi Koizumi, Hiroyuki Ito, Shoji Sunaga, Masaki Ogawa, Erika Tomimatsu

研究成果: ジャーナルへの寄稿記事

1 引用 (Scopus)

抄録

Assumed lighting direction in cast-shadow interpretation was investigated. Experiment 1 used an ambiguous object–shadow-matching task to measure bias in shadow-matching direction. The shadow-matching bias was largest when the lighting direction was on average 38.3° left from above (a median of 25.1°). Experiment 2 tested the effect of body posture (head orientation) on cast-shadow interpretation using stimuli aligned in a head-centrically vertical or horizontal orientation. The below-shadow (light-from-above) bias in the head-centric frame was robust across the sitting upright, reclining-on-the-left-side, reclining-on-the-right-side, and supine conditions. A right-shadow (light-from-left) bias in the head-centric frame was found for the sitting upright and reclining-on-the-right-side conditions. In the reclining-on-the-left-side condition, shadow biases to the gravitational below direction and head-centric right direction may have cancelled each other out. These results are consistent with findings from previous shape-from-shading studies, suggesting that the same light-source assumption is applied to shading and shadow interpretations.

元の言語英語
ジャーナルi-Perception
9
発行部数4
DOI
出版物ステータス出版済み - 7 1 2018

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Head frames
Lighting
Head
Light sources
Light
Experiments
Posture
Direction compound

All Science Journal Classification (ASJC) codes

  • Experimental and Cognitive Psychology
  • Ophthalmology
  • Sensory Systems
  • Artificial Intelligence

これを引用

Assumed Lighting Direction in the Interpretation of Cast Shadows. / Koizumi, Tomomi; Ito, Hiroyuki; Sunaga, Shoji; Ogawa, Masaki; Tomimatsu, Erika.

:: i-Perception, 巻 9, 番号 4, 01.07.2018.

研究成果: ジャーナルへの寄稿記事

Koizumi, Tomomi ; Ito, Hiroyuki ; Sunaga, Shoji ; Ogawa, Masaki ; Tomimatsu, Erika. / Assumed Lighting Direction in the Interpretation of Cast Shadows. :: i-Perception. 2018 ; 巻 9, 番号 4.
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