GENRLUT

Generate at-sensor radiance lookup table


EnvironmentsPYTHON :: EASI :: MODELER
Batch ModeYes
Quick linksDescription :: Parameters :: Parameter descriptions :: Details :: Related

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Description


GENRLUT transforms a MODTRAN 4 "tape7" output file into an at-sensor radiance lookup table. The radiance units used are microwatts/cm^2/nm/sr. This function is designed to be used in combination with GENTP5.
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Parameters


Name Type Length Value range
Output: Output radiance LUT file name * BIN port 1 -    
Tape7 MONDTRA4 File * String 1 -    
Vertical Water Vapor Column Interval Float 0 - 3  
Vertical Water Vapor Column Samples Float 0 - 3  
Aerosol Optical Depth Range Interval Float 0 - 3  
Aerosol Optical Depth Range Samples Float 0 - 3  
Surface Meteorological Range Interval Float 0 - 3  
Surface Meteorological Range Samples Float 0 - 3  
Reflectance Interval * Float 3 - 3  
Reflectance Samples * Float 3 - 3  
Relative View-Solar Azimuth Interval * Float 3 - 3  
Relative View-Solar Azimuth Samples * Float 3 - 3  
View Zenith Angle Interval * Float 3 - 3  
View Zenith Angle Samples * Float 3 - 3  
Solar Zenith Angle Interval * Float 3 - 3  
Solar Zenith Angle Samples * Float 3 - 3  
Scene Elevation Interval * Float 3 - 3  
Scene Elevation Samples * Float 3 - 3  
Sensor Altitude Interval * Float 3 - 3  
Sensor Altitude Samples * Float 3 - 3  

* Required parameter
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Parameter descriptions

Output: Output radiance LUT file name

Specifies the output segment to receive the output radiance LUT.

If no leading path is specified, the file is assumed to be located in the current working directory.

Tape7 MONDTRA4 File

Specifies the name of the "tape7" MODTRAN4 file that contains the results from the MODTRAN4 execution.

Vertical Water Vapor Column Interval

Specifies the vertical water vapor column interval endpoints (in g.cm^2).

This setting must match the Vertical Water Vapor Column Interval setting that was used for the related GENTP5 run.

Vertical Water Vapor Column Samples

Specifies the number of vertical water vapor column samples.

This setting must match the Vertical Water Vapor Column Samples setting that was used for the related GENTP5 run. In particular, if no value was specified for GENTP5, one must not be specified here.

Aerosol Optical Depth Range Interval

Specifies the aerosol optical depth range interval endpoints (at 550 nm).

This setting must match the Aerosol Optical Depth Range Interval setting that was used for the related GENTP5 run. In particular, if no value was specified for GENTP5, one must not be specified here.

Aerosol Optical Depth Range Samples

Specifies the number of aerosol optical depth range samples.

This setting must match the Aerosol Optical Depth Range Samples setting that was used for the related GENTP5 run. In particular, if no value was specified for GENTP5, one must not be specified here.

Surface Meteorological Range Interval

Specifies the surface meteorological range interval endpoints (in km).

This setting must match the Surface Meteorological Range Interval setting that was used for the related GENTP5 run. In particular, if no value was specified for GENTP5, one must not be specified here.

Surface Meteorological Range Samples

Specifies the number of surface meteorological range samples.

This setting must match the Surface Meteorological Range Samples setting that was used for the related GENTP5 run. In particular, if no value was specified for GENTP5, one must not be specified here.

Reflectance Interval

Specifies the reflectance interval endpoints (in percentage).

This setting must match the Reflectance Interval setting that was used for the related GENTP5 run.

Reflectance Samples

Specifies the number of reflectance samples.

This setting must match the Reflectance Samples setting that was used for the related GENTP5 run.

Relative View-Solar Azimuth Interval

Specifies the relative view-solar azimuth (solar azimuth minus view azimuth) interval endpoints (in degrees).

This setting must match the Relative View-Solar Azimuth Interval setting that was used for the related GENTP5 run.

Relative View-Solar Azimuth Samples

Specifies the number of relative view-solar azimuth samples.

This setting must match the Relative View-Solar Azimuth Samples setting that was used for the related GENTP5 run.

View Zenith Angle Interval

Specifies the view zenith angle interval endpoints (in degrees).

This setting must match the View Zenith Angle Interval setting that was used for the related GENTP5 run.

View Zenith Angle Samples

Specifies the number of view zenith angle interval samples.

This setting must match the View Zenith Angle Samples setting that was used for the related GENTP5 run.

Solar Zenith Angle Interval

Specifies the solar zenith angle interval endpoints (in degrees).

This setting must match the Solar Zenith Angle Interval setting that was used for the related GENTP5 run.

Solar Zenith Angle Samples

Specifies the number of solar zenith angle interval samples.

This setting must match the Solar Zenith Angle Samples setting that was used for the related GENTP5 run.

Scene Elevation Interval

Specifies the scene elevation interval endpoints (in meters with respect to the WGS84 vertical datum).

This setting must match the Scene Elevation Interval setting that was used for the related GENTP5 run.

Scene Elevation Samples

Specifies the number of scene elevation samples.

This setting must match the Scene Elevation Samples setting that was used for the related GENTP5 run.

Sensor Altitude Interval

Specifies the sensor altitude interval endpoints (in meters with respect to the WGS84 vertical datum).

This setting must match the Sensor Altitude Interval setting that was used for the related GENTP5 run.

Sensor Altitude Samples

Specifies the number of sensor altitude samples.

This setting must match the Sensor Altitude Interval setting that was used for the related GENTP5 run.

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Details

GENRLUT is designed to be used in combination with GENTP5 and the MODTRAN4 program from Ontar Corporation to produce a radiance lookup table (RLUT) for the atmospheric transformation of remotely sensed images. GENRLUT has been tested with Version 2, Revision 1 of the MODTRAN4 program.

The radiance units used in the generated RLUT are microwatts/cm^2/nm/sr.

The "tape7" file generated by the MODTRAN4 program contains the results of one or more MODTRAN4 runs. GENRLUT transforms this file into an RLUT.

RLUT format

The radiance lookup table (RLUT) is a 9-dimensional array. An RLUT table entry is a pair of real values: Lg, the at-sensor radiance reflected by the target, and Lo, the at-sensor radiance due to all other sources including atmospheric scattering, adjacency effects, and thermally generated radiation.

Each RLUT dimension is labeled according to the physical quantity that it represents. Each dimension corresponds to a physical quantity for which an interval and number of samples was specified in the GENTP5 and GENRLUT runs:

One or more samples are identified on each dimension. The number of samples along a given dimension and the coordinates of those values correspond to the "interval and number of samples" parameter values used for the matching physical quantity in the GENTP5 and GENRLUT runs.

An RLUT is stored exclusively in a PCIDSK binary segment. One RLUT can be stored per segment. All RLUT attributes are saved as metadata for that binary segment.

The following metadata tags are recognized by the RLUT processing algorithms:

Upon saving the RLUT to disk, the RLUT entries are serialized into a system-independent byte stream and written to the binary segment.

Getting MODTRAN4

The MODTRAN4 CDROM and single-user license are available from Ontar Corporation (http://www.ontar.com/Software/pricing.aspx). PCI Geomatics has tested GENTP5 and GENRLUT with Version 2, Revision 1 of the MODTRAN4 software.

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