This task resamples a raster to different dimensions by multiplying the pixel size by a scale factor.

The virtual raster associated with this task is ENVIResampleRaster.

Example


This example opens a 1024 x 1024 pixel raster whose pixel size is 2.8 meters. It multiplies a scale factor of 2.5 to the pixels to produce a raster that is 410 x 410 in size with 7-meter pixels.

; 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('PixelScaleResampleRaster')
 
; Define inputs
Task.INPUT_RASTER = Raster
Task.PIXEL_SCALE = [2.5, 2.5]
 
; 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('PixelScaleResampleRaster')

Input properties (Set, Get): INPUT_RASTER, OUTPUT_RASTER_URI, PIXEL_SCALE, RESAMPLING

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:

AddParameter

Execute

Parameter

ParameterNames

RemoveParameter

Properties


This task inherits the following properties from ENVITask:

COMMUTE_ON_DOWNSAMPLE

COMMUTE_ON_SUBSET

DESCRIPTION

DISPLAY_NAME

NAME

REVISION

TAGS

This task also contains the following properties:

INPUT_RASTER (required)

Specify the raster to resample.

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.

PIXEL_SCALE (required)

Specify a two-element array of positive values that define how each pixel will be resized. Setting this property can result in the resampled raster having slightly different geographic extents than the source raster. Scaled pixels may not exactly cover the same geographic area as the original pixels. The upper-left corners will coincide while the right and bottom edges will be scaled by a sub-pixel amount.

RESAMPLING (optional)

Specify the resampling method.

  • Nearest Neighbor: Uses the nearest pixel without any interpolation.
  • Bilinear (default): Performs a linear interpolation using four pixels to resample.
  • Cubic Convolution: Uses 16 pixels to approximate the sinc function using cubic polynomials to resample the image.

Version History


ENVI 5.2

Introduced

ENVI 5.5

OUTPUT_RASTER_URI now supports '*', which allows OUTPUT_RASTER to be virtual output.

API Version


4.3

See Also


ENVITask, DimensionsResampleRaster Task, MappingResampleRaster Task