posted on 2023-05-25, 22:59authored byWilliams, R, G Rees, Young, ND
This paper describes an image analysis technique developed to identify icebergs depicted in synthetic aperture radar images of Antarctica and to determine the outlines of these icebergs. The technique uses a pixel bonding process to delineate the edges of the icebergs. It then separates them from the background water and sea ice by an edge-guided image segmentation process. Characteristics such as centroid position and iceberg area are calculated for each iceberg segment and placed in a file for input to appropriate statistical data analysis software. The technique has been tested on three ERS-1 SAR sub-images in which it succeeded in identifying virtually all segments containing icebergs of size 6 pixels or larger. The images were first passed through an averaging filter to reduce speckle. This process produced a pixel size of 100 m x 100 m. As implemented, the technique over-estimates iceberg areas by about 20% on average and the detection rate falls off rapidly for icebergs less than six pixels in size. Performance in these areas is expected to improve when additional stages, based on a more detailed analysis of pixel intensity, are implemented.
History
Publication title
International Journal of Remote Sensing
Volume
20
Article number
15-16
Number
15-16
Pagination
3183-3199
Publication status
Published
Rights statement
This is a preprint of an article whose final and definitive form has been published in the INTERNATIONAL JOURNAL OF REMOTE SENSING (c) 1999; INTERNATIONAL JOURNAL OF REMOTE SENSING is available online at: http://journalsonline.tandf.co.uk/