EmissivityFromReferenceChannel Task

This task calculates emissivity and temperature values from thermal infrared radiance data. This method assumes that all the pixels in one band of the thermal infrared data have a constant emissivity.

Example

; Start the application

e = ENVI()

; Open an input file

File = Filepath('qb_boulder_msi', Subdir=['data'], $

  Root_Dir=e.Root_Dir)

Raster = e.OpenRaster(File)

; Create a spectral subset

SubsetTask = ENVITask('SubsetRaster')

SubsetTask.INPUT_RASTER = Raster

SubsetTask.BANDS = [1]

SubsetTask.Execute

;Get subsetted raster

SubsettedRaster = subsetTask.OUTPUT_RASTER

; Get the task from the catalog of ENVITasks

Task = ENVITask('EmissivityFromReferenceChannel')

Task.INPUT_RASTER = subsettedRaster

Task.Execute

; Define inputs

Task.INPUT_RASTER = Raster

; Run the task

Task.Execute

; Get the collection of objects currently in the Data Manager

DataColl = e.Data

; Add the output to the Data Manager

DataColl.Add, Task.OUTPUT_RASTER

DataColl.Add, Task.TEMPERATURE_RASTER

; Display the result

View = e.GetView()

Layer = View.CreateLayer(Task.OUTPUT_RASTER)

Layer = View.CreateLayer(Task.TEMPERATURE_RASTER)

Syntax

Result = ENVITask('EmissivityFromReferenceChannel')

Input properties (Set, Get): DATA_SCALE, EMISSIVITY_VALUE, INPUT_RASTER, OUTPUT_RASTER_URI, TEMPERATURE_RASTER_URI

Output properties (Get only): OUTPUT_RASTER, TEMPERATURE_RASTER

Properties marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Properties marked as "Get" are those whose values you can retrieve but not set.

Methods

This task inherits the following methods from ENVITask:

Properties

This task inherits the following properties from ENVITask:

COMMUTE_ON_DOWNSAMPLE

DATA_SCALE (optional)

Specify the scale factor applied to the data, prior to calculating thermal corrections. This converts the input data to units of W/m²/μm/sr. Valid values are:

1.0 (default)
0.01
0.001

EMISSIVITY_VALUE (required)

Specify the assumed emissivity value. The default value is 0.950000.

INPUT_RASTER (required)

Specify an input raster to process.

OUTPUT_RASTER

This is a reference to the output raster of filetype ENVI.

OUTPUT_RASTER_URI (optional)

Specify a string with the fully qualified filename and path to export the associated OUTPUT_RASTER.

If you set this property to an asterisk symbol (*), the output raster will be virtual and not written to disk.
If you do not specify this property, or set it to an exclamation symbol (!), a temporary file will be created.

TEMPERATURE_RASTER

This is a reference to the output raster of filetype ENVI. The output values are in units of kelvin degrees.

TEMPERATURE_RASTER_URI (optional)

Specify a string with the fully qualified filename and path of the associated TEMPERATURE_RASTER. If you do not specify this property, or set it to an exclamation symbol (!), a temporary file will be created.

Version History

ENVI 5.7

Introduced

API Version

4.3