The Add method adds a new tie point to an ENVITiePointSet object.


This example uses a sample auto-generated tie point file that was created by choosing the default options in the Image Registration workflow, using two input images quickbird_2.4m.dat and ikonos_4.0m.dat. The sample tie point file (SampleTiePoints.pts) and images are available on the ENVI Resource DVD under the /image_reg directory or from the ENVI Tutorials web page. Click the "ENVI Tutorial Data" hyperlink. Copy the files to your local drive. Then edit SampleTiePoints.pts to include the full path to the sample images quickbird_2.4m.dat and ikonos_4.0m.dat.

; Start the application
e = ENVI()
; Open an existing tie point file
tiePointFile = 'SampleTiePoints.pts'
tiePoints = ENVITiePointSet(tiePointFile)
; Add a new tie point
tiePoints.Add, 295.49, 221.58, 543.38, 293.52


ENVITiePointSet.Add, Column1, Row1, Column2, Row2 [, ERROR=variable]



Specify the pixel x-coordinate from the first image.


Specify the pixel y-coordinate from the first image.


Specify the pixel x-coordinate from the second image.


Specify the pixel y-coordinate from the second image.


ERROR (optional)

Set this keyword to a named variable that will contain any error message issued during execution of this routine. If no error occurs, the ERROR variable will be set to a null string (''). If an error occurs and the routine is a function, then the function result will be undefined.

When this keyword is not set and an error occurs, ENVI returns to the caller and execution halts. In this case, the error message is contained within !ERROR_STATE and can be caught using IDL's CATCH routine. See IDL Help for more information on !ERROR_STATE and CATCH.

See Manage Errors for more information on error handling in ENVI programming.

Version History

ENVI 5.2. 1


API Version


See Also