This task applies the Savitsky-Golay smoothing filter to smooth noisy spectral signatures.
Example
e = ENVI()
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
Task = ENVITask('SpectralSmoothing')
Task.INPUT_RASTER = Raster
Task.Execute
e.Data.Add, Task.OUTPUT_RASTER
View = e.GetView()
Layer = View.CreateLayer(Task.OUTPUT_RASTER)
Syntax
Result = ENVITask('SpectralSmoothing')
Input parameters (Set, Get): DEGREE_OF_POLY, INPUT_RASTER, ORDER_OF_DERIVATIVE, OUTPUT_RASTER_URI, PIXELS_TO_LEFT, PIXELS_TO_RIGHT
Output parameters (Get only): OUTPUT_RASTER
Parameters marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Parameters marked as "Get" are those whose values you can retrieve but not set.
Input Parameters
DEGREE_OF_POLY (optional)
Specify an integer less than the filter width (sum of PIXELS_TO_LEFT and PIXELS_TO_RIGHT). Typical values are 2 to 4. The default value is 2.
INPUT_RASTER (required)
Specify the raster on which to perform spectral smoothing.
ORDER_OF_DERIVATIVE (optional)
Specify an integer for the smoothed order derivative of the signal. The default value is 0.
OUTPUT_RASTER_URI (optional)
Specify a string with the fully qualified filename and path of the associated OUTPUT_RASTER.
- If you do not specify this parameter, or set it to an exclamation symbol (!), ENVI creates a temporary file.
- If you set it to the hash symbol (#), ENVI creates a file in the temporary directory, but this file will not be deleted when ENVI closes.
PIXELS_TO_LEFT (optional)
Specify the number of pixels to the left of the data point. Larger values produce a smoother result at the expense of flattening sharp peaks. The default value is 1.
PIXELS_TO_RIGHT (optional)
Specify the number of pixels to the right of the data point. Larger values produce a smoother result at the expense of flattening sharp peaks. The default value is 1.
Output Parameters
OUTPUT_RASTER
This is a reference to the output raster of filetype ENVI.
Methods
Execute
Parameter
ParameterNames
Properties
DESCRIPTION
DISPLAY_NAME
NAME
REVISION
TAGS
Version History
See Also
ENVITask, ENVITask::Parameter