Analysis of target contrast improvement using polarization filtering in the infrared region
Moretz, David Gavin
Cooper, Alfred William Madison
MetadataShow full item record
Computer analysis with IDL was performed on polarized infrared image data obtained during the MAPTIP coastal experiment. Analysis of contrast enhancement of the oceanographic ship Hr. Ms. Tydeman and a Lynx helicopter using polarization filters is presented. Contrast of vertical and horizontal polarized images was determined by two methods. Unpolarized image contrast was developed from polarization data and used to calculate contrast improvement factors for vertical and horizontal polarizations. Background effects upon contrast were explored. Dependence of projected ship area on contrast improvement was analyzed. Vertical and horizontal polarized images were compared to verify preliminary observations of negligible predominant polarization of man-made targets. Results of this analysis confirm that vertically polarized sea background radiance can be reduced by polarization filtering to enhance ship-to-background contrast. Man-made targets appear to present negligible polarization. Sky background immediately above the horizon also appears unpolarized. Combining radiance from both sky background above the horizon and sea background to form an average background reference radiance reduces overall contrast improvement. Ship-to-background contrast should be calculated with respect to the horizon location.
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Pontes, Marcos Cesar (Monterey, California. Naval Postgraduate School, 1998-09);An analysis has been carried out of a data base of polarized long wave infrared images of the instrumented Research Vessel POINT SUR recorded over a period of two days during the EOPACE measurements series in San Diego Bay ...
Loo, Fook Leong (Monterey California. Naval Postgraduate School, 2007-03);Passive infrared (IR) imagers, using intensity contrast for target detection, are often limited by low target-background contrast. Detecting stationary targets against cluttered backgrounds presents an even bigger challenge. ...
Tung, Yan Foo (Monterey, California. Naval Postgraduate School, 2003-12);The infrared (IR) radiation emitted or reflected in an off-normal direction from a smooth surface is partially polarized. This principle can be used for enhanced discrimination of targets from backgrounds in marine ...