ReprojectRaster Task

This task reprojects a raster to a standard spatial reference based on a specified coordinate system. It transforms and resamples coordinates from one spatial reference (standard, RPC, or pseudo) to a standard spatial reference in the specified coordinate system. It retains the pixel size of the input image.

This task offers a quick way to convert non-standard projections to a standard projection. In the case of RPCs, the RPCOrthorectification task provides a more accurate orthorectification.

ENVIReprojectRaster does not support geographic lookup tables (GLTs). Use the ReprojectGLT task instead.

The virtual raster associated with this task is ENVIReprojectRaster.

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('ReprojectRaster')

; Get the

; NAD_1983_StatePlane_Colorado_North_FIPS_0501_Feet

; coordinate system

CoordSys = ENVICoordSys(COORD_SYS_CODE=2231)

; Define inputs

Task.COORD_SYS = CoordSys

Task.INPUT_RASTER = Raster

; 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('ReprojectRaster')

Input parameters (Set, Get): COORD_SYS, DATA_IGNORE_VALUE, GRID_SPACING, INPUT_RASTER, OUTPUT_RASTER_URI, RESAMPLING, TRANSFORM

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

COORD_SYS (required)

Specify an ENVICoordSys object representing the coordinate system to which to transform the image.

DATA_IGNORE_VALUE (optional)

Specify a unique data value for background pixels in the output raster.

GRID_SPACING (optional)

Specify the grid spacing (in pixels) to use for reprojection.

INPUT_RASTER (required)

Specify the raster to reproject. The raster must have a standard, RPC, or pseudo spatial reference defined.

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.

RESAMPLING (optional)

Specify the resampling method to use when creating the spatial grid:

Nearest Neighbor (default): Uses the nearest pixel without any interpolation.
Bilinear: 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.

TRANSFORM (optional)

Specify the method used to reproject the raster.

Polynomial
Triangulation (default)
Rigorous

Output Parameters

OUTPUT_RASTER

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

Methods

Execute

Parameter

ParameterNames

Properties

Version History

ENVI 5.3	Introduced
ENVI 5.5	OUTPUT_RASTER_URI now supports '*', which allows OUTPUT_RASTER to be virtual output.
ENVI 5.5.2	Added DATA_IGNORE_VALUE, GRID_SPACING, and TRANSFORM parameters. Also, the task has been refactored and no longer references the ENVIReprojectRaster virtual raster.