User's Guide

MGRID

Creates a geometric mapping grid for the specified frame.

Function:

Creates a geometric mapping grid for the specified frame. This grid is then used to geometrically correct the cutline that corresponds to the specified frame.

Parameters:

FRAMNUM
Frame number. The frame number of the image for which the geometric grid is created.

NLGRID(-- )
Number of lines per grid. The number of lines contained in each output grid cell. If NLGRID is NULL, the geometric mapping grid size is set to the maximum and then reduced according to the TOLVAL parameter.

NSGRID(-- )
Number of samples per grid. The number of samples contained in each output grid cell. If NSGRID is NULL, the geometric mapping grid size is set to the maximum and then reduced according to the TOLVAL parameter.

TOLVAL(0.015625)
Tolerance value. Tolerance (in pixel values) for reducing the density of geometric mapping grid points. If NLGRID and NSGRID are not NULL, the TOLVAL parameter is ignored.

DELFLG(YES)
Delete flag. Specifies whether or not the temporary files should be deleted when the procedure completes or aborts.


  = YES:  Delete temporary files.  
  = NO:   Do not delete temporary files.

Example:

  1. LAS> mgrid framnum=1 nlgrid=100 nsgrid=100 delflg="yes"

    Assuming that the LAMS global $IMAGE = ("US1","US2"), FINITE creates a geometric grid from the control points from US1.GCP and US1.CRN which has 100 lines and 100 samples between each grid cell. This grid is then used by POLYGEO to correct the cutline polygon in US1.CUT. The geometric grid (US1.GGR) is saved to be used by MGMAP to geometrically correct the original image. The temporary files are deleted.

Description/Algorithm:

FINITE will use the IBIS ground control and corner files to create a geometric grid. This grid is used by POLYGEO to correct the cutline and can be used by MGMAP to correct the input image. Error Messages: Error messages are displayed from the called routines.

User Notes:

  1. Any changes made to the routines CMCOPY, CMDEL, CMRENAME, FINITE, INSCOUNT, MERGE, MF, MTB2MGR, MTBSORT, POLYGEO, and ROWOP may affect the operation of this routine.

  2. Related Large Area Mosaicking System (LAMS) procedure functions include MCTP, MCUT, MTIE, MEDIT, MCRN, MAVE, MGMAP, and MRAD.