Concepts for compensation of wave effects when measuring through water surfaces in photogrammetric applications

Research output: Contribution to book/conference proceedings/anthology/reportConference contributionContributedpeer-review

Contributors

Abstract

A common problem when imaging and measuring through moving water surfaces is the quasi-random refraction caused by waves. The article presents two strategies to overcome this problem by lowering the complexity down to a planer air/water interface problem. In general, the methods assume that the shape of the water surface changes randomly over time and that the water surface moves around an idle-state (calm planar water surface). Thus, moments at which the surface normal is orientated vertically should occur more frequently than others should. By analysing a sequence of images taken from a stable camera position these moments could be identified – this can be done in the image or object space. It will be shown, that a simple median filtering of grey values in each pixel position can provide a corrected image freed from wave and glint effects. This should have the geometry of an image taken through calm water surface. However, in case of multi camera setups, the problem can be analysed in object space. By tracking homological underwater features, sets of image rays hitting accidently horizontal orientated water surface areas can be identified. Both methods are described in depth and evaluated on real and simulated data.

Details

Original languageEnglish
Title of host publicationISPRS TC II Mid-term Symposium “The Role of Photogrammetry for a Sustainable World”
EditorsAlper Yilmaz, Jan Dirk Wegner, Rongjun Qin
Pages289–295
Number of pages7
Volume48-2-2024
Publication statusPublished - 2024
Peer-reviewedYes

Publication series

SeriesInternational Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences
VolumeXLVIII-2-2024
ISSN1682-1750

External IDs

Scopus 85197350379

Keywords