Extraction of Yardang Characteristics Using Object-Based Image Analysis and Canny Edge Detection Methods
Open Access
- 22 February 2020
- journal article
- research article
- Published by MDPI AG in Remote Sensing
- Vol. 12 (4), 726
- https://doi.org/10.3390/rs12040726
Abstract
Parameters of geomorphological characteristics are critical for research on yardangs. However, methods which are low-cost, accurate, and automatic or semi-automatic for extracting these parameters are limited. We present here semi-automatic techniques for this purpose. They are object-based image analysis (OBIA) and Canny edge detection (CED), using free, very high spatial resolution images from Google Earth. We chose yardang fields in Dunhuang of west China to test the methods. Our results showed that the extractions registered an overall accuracy of 92.26% with a Kappa coefficient of agreement of 0.82 at a segmentation scale of 52 using the OBIA method, and the exaction of yardangs had the highest accuracy at medium segmentation scales (138, 145). Using CED, we resampled the experimental image subset to a series of lower spatial resolutions for eliminating noise. The total length of yardang boundaries showed a logarithmically decreasing (R2 = 0.904) trend with decreasing spatial resolution, and there was also a linear relationship between yardang median widths and spatial resolutions (R2 = 0.95). Despite the difficulty of identifying shadows, the CED method achieved an overall accuracy of 89.23% with a kappa coefficient of agreement of 0.72, similar to that of the OBIA method at medium segmentation scale (138).This publication has 45 references indexed in Scilit:
- Wind erosion under cold climate: A Pleistocene periglacial mega-yardang system in Central Europe (Western Pannonian Basin, Hungary)Geomorphology, 2011
- Object-oriented mapping of landslides using Random ForestsRemote Sensing of Environment, 2011
- Per-pixel vs. object-based classification of urban land cover extraction using high spatial resolution imageryRemote Sensing of Environment, 2011
- Wind Erosion in DrylandsPublished by Wiley ,2011
- Mega‐Yardangs: A Global AnalysisGeography Compass, 2006
- On the Canny edge detectorPattern Recognition, 2001
- Characterizing lineaments from satellite images and field studies in the central Ebro basin (NE Spain)International Journal of Remote Sensing, 1998
- Wind-Related Features and Processes on Venus: Summary of Magellan ResultsIcarus, 1995
- Evolution of the yardangs at Rogers Lake, CaliforniaGSA Bulletin, 1984
- The geomorphology of MarsProgress in Physical Geography: Earth and Environment, 1981