Departmental Papers (CIS)

Date of this Version

September 2002

Document Type

Journal Article


Copyright 2002 IEEE. Reprinted from IEEE Transactions on Pattern Analysis and Machine Intelligence, Volume 24, Issue 9, September 2002, pages 1286-1290.
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In the energy spectrum of an occlusion sequence, the distortion term has the same orientation as the velocity of the occluding signal. Recent works claimed that this oriented structure can be used to distinguish the occluding velocity from the occluded one. Here, we argue that the orientation structure of the distortion cannot always work as a reliable feature due to the rapidly decreasing energy contribution. This already weak orientation structure is further blurred by a superposition of distinct distortion components. We also indicate that the superposition principle of Shizawa and Mase for multiple motion estimation needs to be adjusted.


Optical flow, occlusion, motion discontinuities, spectral analysis



Date Posted: 05 November 2004

This document has been peer reviewed.