両眼視差とキャストシャドウによる奥行き知覚の相互作用

抄録

A cast shadow occurs on a floor when an object occludes the illumination source from above. It is known that in a two-dimensional picture this shadow has an important role in the perception of the depth between an object and the floor. Here, we report the results of an investigation of the interaction of perceived depths performed by using binocular disparity and a cast shadow. The results rejected the winner-takes-all model where binocular disparity overrides the cast shadow. The results also indicated that both can work to produce the perception of depth. To account well for the data, we adopted a modified linear combination model for the light-source directions that subjects assume. Significant knowledge was acquired for not only bringing the visual processing of depth perception into the open, but also for creating three-dimensional computer graphics.