Gamma LAT: Reference Manual

wolf

ANSI-C program: wolf.c

NAME
wolf: Calculate Wolf coherence matrix from H and V polarized SLC images

SYNOPSIS
wolf <SLC-1> <SLC-2> <SLC1_par> <SLC2_par> <J> <J_par> <rlks> <azlks> [loff] [nlines]

<SLC-1>	(input) HH, VV, RH, LH single-look complex image (scomplex or fcomplex format)
<SLC-2>	(input) HV, VH, RV, LV single-look complex image coregistered with SLC-1 (scomplex or fcomplex format) NOTE: 1. SLC images must be a co-pol and cross-pol pair with the same transmit polarization and linear receive polarization (HH, HV), (VV, VH), (RH, RV), or (LH, LV) 2. SCOMPLEX SLC data are scaled by .001 before calculations are performed
<SLC1_par>	(input) SLC image parameter file of SLC-1
<SLC2_par>	(input) SLC image parameter file of SLC-2 coregistered with SLC-1
<J>	(output) root file name of coherence matrix elements (e.g. scene_id): .j11, .j22, (float), .j12 (fcomplex) NOTE: expressed in the H,V polarization basis, the coherence matrix elements are given by: J11: <E_h E_h* > J12: <E_h E_v> J21: <E_v E_h> J22: <E_v E_v*>
<J_par>	(output) image parameter file associated with the coherence parameter data files (enter - for none)
<rlks>	number of range looks used to calculate coherence
<azlks>	number of azimuth looks used to calculate coherence
[loff]	offset to starting line (default: 0)
[nlines]	number of SLC lines to process (enter - for default: entire file)

EXAMPLE
wolf 20080415_HH.slc 20080415_HV.slc 20080415_HH.slc.par 20080415_HV.slc.par 20080415_HH_HV 20080415_HH_HV.mli.par 2 4

This calculates the 4 coherence matrix elements J11, J12, J21, and J22 and stores them in the files 20080415_HH_HV.j11, 20080415_HH_HV.j12, 20080415_HH_HV.j21, 20080415_HH_HV.j22

DESCRIPTION

The Wolf coherence matrix describes the polarization state of an electromagnetic field [1] and are related to the Stokes parameters see http://en.wikipedia.org/wiki/Stokes_parameters. The Stokes parameters can be calculated from the Wolf coherence matrix and the opposite is also true [2].

The program wolf calculates the following terms given linear polarized H and V SLC radar data as input:

J11: <E_h E_h* >
J12: <E_h E_v*>
J21: <E_v E_h*>
J22: <E_v E_v*>

Where <> denotes a spatial average over a window. The user specifies the averaging window dimensions rlks and azlks.
The output files J11 and J12 are real valued and the elements J12 and J21 are complex valued.

The user can also specify the offset to the starting line and the number of lines for calculation.

[1] Max Born and Emil Wolf, Principles of Optics (7th ed), Chapter 10, Pergamon Press, 1999.

[2] S.R. Cloude, Polarisation: Applications in Remote Sensing, Chapter 2, Oxford University Press, Oxford, 2010.

SEE ALSO

typedef_ISP.h, stokes, stokes_qm