Shadow Probability of Detection and False Alarm for MedianFiltered SAR Imagery
Abstract
Median filtering reduces speckle in synthetic aperture radar (SAR) imagery while preserving edges, at the expense of coarsening the resolution, by replacing the center pixel of a sliding window by the median value. For shadow detection, this approach helps distinguish shadows from clutter more easily, while preserving shadow shape delineations. However, the nonlinear operation alters the shadow and clutter distributions and statistics, which must be taken into consideration when computing probability of detection and false alarm metrics. Depending on system parameters, median filtering can improve probability of detection and false alarm by orders of magnitude. Herein, we examine shadow probability of detection and false alarm in a homogeneous, ideal clutter background after median filter postprocessing. Some comments on multilook processing effects with and without median filtering are also made.
 Authors:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States). ISR Analysis and Applications Dept.
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States). ISR Mission Engineering Dept.
 General Atomics Aeronautical Systems, Inc., San Diego, CA (United States). Mission Systems
 Publication Date:
 Research Org.:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States); General Atomics Aeronautical Systems, Inc., San Diego, CA (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA); General Atomics Aeronautical Systems, Inc. (GAASI) (United States)
 OSTI Identifier:
 1323596
 Report Number(s):
 SAND20144877
521035
 DOE Contract Number:
 AC0494AL85000
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 47 OTHER INSTRUMENTATION
Citation Formats
Raynal, Ann Marie, Doerry, Armin Walter, Miller, John A., Bishop, Edward E., and Horndt, Volker. Shadow Probability of Detection and False Alarm for MedianFiltered SAR Imagery. United States: N. p., 2014.
Web. doi:10.2172/1323596.
Raynal, Ann Marie, Doerry, Armin Walter, Miller, John A., Bishop, Edward E., & Horndt, Volker. Shadow Probability of Detection and False Alarm for MedianFiltered SAR Imagery. United States. doi:10.2172/1323596.
Raynal, Ann Marie, Doerry, Armin Walter, Miller, John A., Bishop, Edward E., and Horndt, Volker. 2014.
"Shadow Probability of Detection and False Alarm for MedianFiltered SAR Imagery". United States.
doi:10.2172/1323596. https://www.osti.gov/servlets/purl/1323596.
@article{osti_1323596,
title = {Shadow Probability of Detection and False Alarm for MedianFiltered SAR Imagery},
author = {Raynal, Ann Marie and Doerry, Armin Walter and Miller, John A. and Bishop, Edward E. and Horndt, Volker},
abstractNote = {Median filtering reduces speckle in synthetic aperture radar (SAR) imagery while preserving edges, at the expense of coarsening the resolution, by replacing the center pixel of a sliding window by the median value. For shadow detection, this approach helps distinguish shadows from clutter more easily, while preserving shadow shape delineations. However, the nonlinear operation alters the shadow and clutter distributions and statistics, which must be taken into consideration when computing probability of detection and false alarm metrics. Depending on system parameters, median filtering can improve probability of detection and false alarm by orders of magnitude. Herein, we examine shadow probability of detection and false alarm in a homogeneous, ideal clutter background after median filter postprocessing. Some comments on multilook processing effects with and without median filtering are also made.},
doi = {10.2172/1323596},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2014,
month = 6
}

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