PSINTRAT

Description

PSINTRAT creates an image of the intensity ratio for two polarizations of a dual-polarization, compact-polarization, or quad-polarization polarimetric SAR (POLSAR) image. Synthesized polarizations can be used when the input is full-quad data. The intensity ratio image can be written in the linear or decibel scale.

Parameters

Name	Type	Caption	Length	Value range
FILI*	String	Input polarimetric SAR image	1 - 192
FILO*	String	Output intensity ratio raster	1 - 192
POL1	String	First input polarization	0 - 2	Default: HH
POL2	String	Second input polarization	0 - 2	Default: VV
SCALETYP	String	Scaling	0 - 7	Decibel | Linear Default: Linear
MONITOR	String	Monitor mode	0 - 3	ON, OFF Default: ON

* Required parameter

Parameter descriptions

FILI

The name of the input polarimetric SAR data set, which must be either dual-polarization, compact-polarization, or quad-polarization data. The input data set must be in one of the following matrix formats: detected, scattering, covariance, coherence, or Kennaugh. To minimize noisy results, it is recommended that the input data set have an equivalent number of looks (ENL) of at least 25, which can be achieved by applying a polarimetric filter, such as a boxcar filter, when the input data set is single-look complex.

The input file must be a data set that has already been imported into the PCIDSK (.pix) format by SARINGEST. Input can also be the key-file name of any GDB-supported POLSAR data set in its distribution format. For more information, including a complete list of supported POLSAR sensors and data products, follow the link to SARINGEST at the end of this topic.

FILO

The name of output file that will hold the intensity ratio, where POL1 is equal to the numerator and POL2 is equal to the denominator. The output file has the same dimensions as the input file, and one channel that contains the intensity ratio of the two selected or synthesized polarizations, stored in floating-point pixel values.

The file name you specify must not already exist.

POL1

The first polarization in the input file to use. The default value is HH.

With full-quad data sets, you can, as an option, synthesize any polarization of interest. For more information, follow the link to PSPOLSYN at the end of this topic, and see the Details section.

Standard configurations, such as linear-horizontal (H), linear-vertical (V), left-circular (L), and right-circular (R) are supported. Non-standard configurations require four floating-point values; orientation and ellipticity for transmit, followed by orientation and ellipticity for receive. Valid orientation angles range from -90 to 90. Valid ellipticity angles range from -45 to 45.

• rh: case-insensitive, predefined transmit and receive
• Rh: case-insensitive, predefined transmit and receive
• rH: case-insensitive, predefined transmit and receive
• 0,-45,H: transmit TPSI and TCHI followed by predefined receive
• 0,-45,h: transmit TPSI and TCHI followed by predefined receive
• R,0,0: predefined transmit followed by receive RPSI and RCHI
• r,0,0: predefined transmit followed by receive RPSI and RCHI
• 0,-45,0,0: transmit TPSI and TCHI followed by receive RPSI and RCHI

This parameter is optional.

POL2

The second polarization in the input file to use. The default value is VV. The behavior of this parameter is identical to that of POL1.

This parameter is optional.

SCALETYP

The scaling (linear or decibel) of pixel values in the output image. The default value is Linear.

This parameter is optional.

MONITOR

The program progress can be monitored by printing the percentage of processing completed. A system parameter, MONITOR, controls this activity.

Available options are:

• ON: Turns the monitor ON (default)
• OFF: Turns the monitor OFF (recommended if running in batch or background mode)

Details

PSINTRAT calculates the intensity ratio between two polarizations of a dual-polarization, compact-polarization, or quad-polarization polarimetric SAR image. The intensity ratio is defined as the ratio of the powers (intensities) of the two selected polarization channels.

Any combination from the available polarizations can be selected. To avoid extremely large output values (due to dividing by a very small number), the polarization with the weaker return should generally be selected as the numerator; that is, POL1, when using linear scaling.

If one or more of the polarization strings are not valid or if the specified polarization does not exist in the dual-pol or compact input file, processing fails, and an error message displays.

If the intensity of the second polarization at a pixel is zero, the intensity ratio value depends on the output scaling. For linear scaling, the ratio value is set to 0. For decibel scaling, the ratio value is set to -10000.0.

Examples

Create an intensity ratio for the two copolarizations of a RADARSAT-2 data set that is already imported into the PCIDSK (.pix) format.

EASI>FILI="rsat2.pix" 
EASI>FILO="rsat2_intrat_HH_VV.pix"
EASI>POL1="HH"
EASI>POL2="VV"
EASI>SCALETYP=""
EASI>run PSINTRAT
            

Create an intensity ratio for the two synthesized polarizations (RR and RL) from a RADARSAT-2 data set that is already imported into the PCIDSK (.pix) format.

EASI>FILI="rsat2_full_quad.pix" 
EASI>FILO="rsat2_intrat_RR_RL.pix"
EASI>POL1="RR"
EASI>POL2="RL"
EASI>SCALETYP=""
EASI>run PSINTRAT
			

Create an intensity ratio for the two compact polarizations generated by a RADARSAT-2 data set that is already imported into the PCIDSK (.pix) format.

EASI>FILI="rsat2.pix" 
EASI>FILO="rsat2_compact_RH_RV.pix"
EASI>COMPTY="CTLR"


EASI>FILI="rsat2_compact_RH_RV.pix"
EASI>FILO="rsat2_intrat_RH_RV.pix"
EASI>POL1="RH"
EASI>POL2="RV"
EASI>SCALETYP="decibel"
EASI>run PSINTRAT
			
			

Acknowledgements

PCI Geomatics gratefully acknowledges the financial support provided by the Canadian Space Agency through the Earth Observation Application Development Program (EOADP), contract number 9F028-034946.