Analysis of Occluding Contour
Almost nothing can be deduced about a general 3-D surface given only its occluding contours in an image, yet contour information is easily and effectively used by us to infer the shape of a surface. Therefore, implicit in the perceptual analysis of occluding contour must lie various assumption...
| Main Author: | |
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| Language: | en_US |
| Published: |
2004
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| Online Access: | http://hdl.handle.net/1721.1/6249 |
| _version_ | 1811074765766524928 |
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| author | Marr, D. |
| author_facet | Marr, D. |
| author_sort | Marr, D. |
| collection | MIT |
| description | Almost nothing can be deduced about a general 3-D surface given only its occluding contours in an image, yet contour information is easily and effectively used by us to infer the shape of a surface. Therefore, implicit in the perceptual analysis of occluding contour must lie various assumptions about the viewed surfaces. The assumptions that seem most natural are (a) that the distinction between convex and concave segments reflects real properties of the viewed surface; and (b) that contiguous portions of contour arise from contiguous parts of the viewed surface ??e. there are no invisible obscuring edges. It is proved that, for smooth surfaces, these assumptions are essentially equivalent to assuming that the viewed surface is a generalized cone. Methods are defined for finding the axis of such a cone, and for segmenting a surface constructed of several cones into its components, whose axes can then be found separately. These methods, together with the algorithms for implementing them devised by Vatan & Marr (1977), provide one link between an uninterpreted figure extracted from an image, and the 3-D representation theory of Marr and Nishihara (1977). |
| first_indexed | 2024-09-23T09:55:01Z |
| id | mit-1721.1/6249 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T09:55:01Z |
| publishDate | 2004 |
| record_format | dspace |
| spelling | mit-1721.1/62492019-04-12T08:29:52Z Analysis of Occluding Contour Marr, D. Almost nothing can be deduced about a general 3-D surface given only its occluding contours in an image, yet contour information is easily and effectively used by us to infer the shape of a surface. Therefore, implicit in the perceptual analysis of occluding contour must lie various assumptions about the viewed surfaces. The assumptions that seem most natural are (a) that the distinction between convex and concave segments reflects real properties of the viewed surface; and (b) that contiguous portions of contour arise from contiguous parts of the viewed surface ??e. there are no invisible obscuring edges. It is proved that, for smooth surfaces, these assumptions are essentially equivalent to assuming that the viewed surface is a generalized cone. Methods are defined for finding the axis of such a cone, and for segmenting a surface constructed of several cones into its components, whose axes can then be found separately. These methods, together with the algorithms for implementing them devised by Vatan & Marr (1977), provide one link between an uninterpreted figure extracted from an image, and the 3-D representation theory of Marr and Nishihara (1977). 2004-10-04T14:47:18Z 2004-10-04T14:47:18Z 1976-10-01 AIM-372 http://hdl.handle.net/1721.1/6249 en_US AIM-372 4024834 bytes 2916206 bytes application/postscript application/pdf application/postscript application/pdf |
| spellingShingle | Marr, D. Analysis of Occluding Contour |
| title | Analysis of Occluding Contour |
| title_full | Analysis of Occluding Contour |
| title_fullStr | Analysis of Occluding Contour |
| title_full_unstemmed | Analysis of Occluding Contour |
| title_short | Analysis of Occluding Contour |
| title_sort | analysis of occluding contour |
| url | http://hdl.handle.net/1721.1/6249 |
| work_keys_str_mv | AT marrd analysisofoccludingcontour |