Abstract
It has been known that monocular and binocular cues as a primal visual information mainly produce depth perception. Our question is whether this perception mechanism can be affected by cognitive cue, such as a shadow of an object on a surface making locate at discrepant depth defined by binocular cue of that object. To investigate this question, we measured a subjective depth between a reference rectangle, which has a certain depth defined by a binocular disparity, and a test rectangle which is or is not as a candidate of a shadow of the reference rectangle. In the case of a candidate of the shadow, some part of the test rectangle spatially overlapped (occluded) over the reference rectangle, and the test rectangle did not overlap over the reference rectangle in the case of a non-candidate. The subjective depth for the both cases was measured for five undergraduates as a function of a binocular disparity difference between the test and reference rectangles. We found that in the candidate case, the reference rectangle was always perceived in front of the test rectangle against any depth difference caused by the binocular disparity cues, whereas the perceived depth of the reference rectangle to the test rectangle was followed by the depth information defined by the binocular disparity in the non-candidate case. That is, a cognitive cue such that the test rectangle was cognitively casted on the reference rectangle as a shadow determined the perceived depth prior to low level cues such as the binocular disparity and the occlusion. These suggested that if there is discrepancy of the depth information between low level cues and cognitive cue, the latter is dominantly employed as the depth information.
Meeting abstract presented at VSS 2018