HighPassFilter Task

This task performs high pass filtering. Pixels in the input raster that are masked out or with a data-ignore value set will not be included in the convolution calculations and will be set to the data-ignore value in the output raster.

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)

; Get the task from the catalog of ENVITasks

Task = ENVITask('HighPassFilter')

; Define inputs

Task.INPUT_RASTER = Raster

Task.KERNEL_SIZE = [5,5]

; Run the task

Task.Execute

; Get the collection of data objects currently available in the Data Manager

DataColl = e.Data

; Add the output to the Data Manager

DataColl.Add, Task.OUTPUT_RASTER

; Display the result

View = e.GetView()

Layer = View.CreateLayer(Task.OUTPUT_RASTER)

Syntax

Result = ENVITask('HighPassFilter')

Input properties (Set, Get): ADD_BACK, DATA_IGNORE_VALUE, INPUT_RASTER, KERNEL_SIZE, OUTPUT_RASTER_URI

Output properties (Get only): OUTPUT_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

ADD_BACK (optional)

Specify a filter add-back percentage value between 0.0 and 1.0. A value of 1.0 is equal to 100%.

DATA_IGNORE_VALUE (optional)

Specify a unique data value for pixels in the output raster that have a non-zero pixel state value.

INPUT_RASTER (required)

Specify a raster on which to perform high pass filtering.

KERNEL_SIZE (optional)

Specify a two-element array [n,m] as the kernel size, where n is the number of columns and m is the number of rows. The default value is [3,3].

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 of the associated OUTPUT_RASTER. If you do not specify this property, or set it to an exclamation symbol (!), a temporary file will be created.

Version History

ENVI 5.3	Introduced
ENVI 5.6	Added DATA_IGNORE_VALUE property

API Version

4.2