OPTICAL FLOW APPLIED TO TIME-LAPSE IMAGE SERIES TO ESTIMATE GLACIER MOTION IN THE SOUTHERN PATAGONIA ICE FIELD
In this work, we assessed the feasibility of using optical flow to obtain the motion estimation of a glacier. In general, former investigations used to detect glacier changes involve solutions that require repeated observations which are many times based on extensive field work. Taking into accoun...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2016-06-01
|
| Series: | The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences |
| Online Access: | https://www.int-arch-photogramm-remote-sens-spatial-inf-sci.net/XLI-B8/503/2016/isprs-archives-XLI-B8-503-2016.pdf |
| Summary: | In this work, we assessed the feasibility of using optical flow to obtain the motion estimation of a glacier. In general, former
investigations used to detect glacier changes involve solutions that require repeated observations which are many times based on
extensive field work. Taking into account glaciers are usually located in geographically complex and hard to access areas, deploying
time-lapse imaging sensors, optical flow may provide an efficient solution at good spatial and temporal resolution to describe mass
motion. Several studies in computer vision and image processing community have used this method to detect large displacements.
Therefore, we carried out a test of the proposed Large Displacement Optical Flow method at the Viedma Glacier, located at South
Patagonia Icefield, Argentina. We collected monoscopic terrestrial time-lapse imagery, acquired by a calibrated camera at every 24
hour from April 2014 until April 2015. A filter based on temporal correlation and RGB color discretization between the images was
applied to minimize errors related to changes in lighting, shadows, clouds and snow. This selection allowed discarding images that
do not follow a sequence of similarity. Our results show a flow field in the direction of the glacier movement with acceleration in the
terminus. We analyzed the errors between image pairs, and the matching generally appears to be adequate, although some areas show
random gross errors related to the presence of changes in lighting. The proposed technique allowed the determination of glacier
motion during one year, providing accurate and reliable motion data for subsequent analysis. |
|---|---|
| ISSN: | 1682-1750 2194-9034 |