Abstract
When a shape moves behind a very narrow window, or “slit,” the entire shape can be recognized, although at any instant only meaningless fragments are visible. In some manner, the human visual system has the ability to piece together these sequential fragments into a coherent shape that is seen as moving across the largely occluded field. As a first step toward understanding how this feat may be accomplished, we show some minimal conditions for recovering the direction and speed of motion of an unknown shape moving behind a slit. Two important conditions are that the object be rigid and that its motion be a simple transition in the image plane.
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William Gilson provided technical help in the preparation of the manuscript This research was supported by the NSF-Information Science and Technology Division, Grant IST-8312240.
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Shimojo, S., Richards, W. “Seeing” shapes that are almost totally occluded: A new look at Parks’s camel. Perception & Psychophysics 39, 418–426 (1986). https://doi.org/10.3758/BF03207070
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DOI: https://doi.org/10.3758/BF03207070