Bias in Visual Motion Processes: A Theory Predicting Illusions
نویسندگان
چکیده
The first step in the interpretation of video sequences is the estimation of spatio-temporal image representations, that is the image motion or the correspondence of points or lines. Noise in the data, however, causes a serious problem for their estimation; in particular, it causes bias. As a result the location of image points, the orientation of image lines and the length and orientation of image motion vectors are estimated erroneously. It is suggested that machine vision systems processing video should include statistical procedures to alleviate the bias. However, complete correction in general does not appear to be feasible, and this provides an explanation for most well-known geometrical optical illusions, such as the café wall, the Zöllner, the Poggendorff illusion and other recently discovered illusions of movement.
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