Computations Underlying the Measurement of Visual Motion
The organization of movement in a changing image provides a valuable source of information for analyzing the environment in terms of objects, their motion in space, and their three-dimensional structure. This movement may be represented by a two-dimensional velocity field that assigns a direct...
| Main Author: | |
|---|---|
| Language: | en_US |
| Published: |
2004
|
| Online Access: | http://hdl.handle.net/1721.1/5641 |
| _version_ | 1811072206296317952 |
|---|---|
| author | Hildreth, Ellen C. |
| author_facet | Hildreth, Ellen C. |
| author_sort | Hildreth, Ellen C. |
| collection | MIT |
| description | The organization of movement in a changing image provides a valuable source of information for analyzing the environment in terms of objects, their motion in space, and their three-dimensional structure. This movement may be represented by a two-dimensional velocity field that assigns a direction and magnitude of velocity to elements in the image. This paper presents a method for computing the velocity field, with three main components. First, initial measurements of motion in the image take place at the location of significant changes, which give rise to zero-crossings in the output of the convolution of the image with a *** operator. The initial motion measurements provide the component of velocity in the direction perpendicular to the local orientation of the zero-crossing contours. Second, these initial measurements are integrated along contours to compute the two-dimensional velocity field. Third, an additional constraint of smoothness of the velocity field, based on the physical constraint that surfaces are generally smooth, allows the computation of a unique velocity field. The details of an algorithm are presented, with results of the algorithm applied to artificial and natural image sequences. |
| first_indexed | 2024-09-23T09:02:16Z |
| id | mit-1721.1/5641 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T09:02:16Z |
| publishDate | 2004 |
| record_format | dspace |
| spelling | mit-1721.1/56412019-04-10T20:22:46Z Computations Underlying the Measurement of Visual Motion Hildreth, Ellen C. The organization of movement in a changing image provides a valuable source of information for analyzing the environment in terms of objects, their motion in space, and their three-dimensional structure. This movement may be represented by a two-dimensional velocity field that assigns a direction and magnitude of velocity to elements in the image. This paper presents a method for computing the velocity field, with three main components. First, initial measurements of motion in the image take place at the location of significant changes, which give rise to zero-crossings in the output of the convolution of the image with a *** operator. The initial motion measurements provide the component of velocity in the direction perpendicular to the local orientation of the zero-crossing contours. Second, these initial measurements are integrated along contours to compute the two-dimensional velocity field. Third, an additional constraint of smoothness of the velocity field, based on the physical constraint that surfaces are generally smooth, allows the computation of a unique velocity field. The details of an algorithm are presented, with results of the algorithm applied to artificial and natural image sequences. 2004-10-01T20:17:57Z 2004-10-01T20:17:57Z 1984-03-01 AIM-761 http://hdl.handle.net/1721.1/5641 en_US AIM-761 53 p. 9432301 bytes 7417816 bytes application/postscript application/pdf application/postscript application/pdf |
| spellingShingle | Hildreth, Ellen C. Computations Underlying the Measurement of Visual Motion |
| title | Computations Underlying the Measurement of Visual Motion |
| title_full | Computations Underlying the Measurement of Visual Motion |
| title_fullStr | Computations Underlying the Measurement of Visual Motion |
| title_full_unstemmed | Computations Underlying the Measurement of Visual Motion |
| title_short | Computations Underlying the Measurement of Visual Motion |
| title_sort | computations underlying the measurement of visual motion |
| url | http://hdl.handle.net/1721.1/5641 |
| work_keys_str_mv | AT hildrethellenc computationsunderlyingthemeasurementofvisualmotion |