makeground Documentation

makeground - Create ground points from match point sets, cube list
makeground creates a ground point file from a match point file and a
list of cube files that contain all the match points.  The MATFROM
match point file contains the points from which to generate a ground
point from each set.  Each point set can have either an explicit
ground point as denoted by a "G" classification for a match point or
makeground will automatically select one (SELECT="YES").  The only
criteria used to select a ground point in a set of match points is
it picks the first occuring level 2 image in the set.  There may be
more than one level 2 match point in a set but only the first one
is selected.  It is *not* guaranteed that the first occuring level 2
point in MATFROM or the first occuring level 2 cube in FROMLIST will
actually be the one selected.  This is due to unpredictability in
sorting the lists.  At any rate, when a match point is selected as
a ground point, its classification is changed to reflect this and a
new match point file is written to MATTO.  All ground points are then
written to GRNDTO.

makeground requires a DTM file that contains radius data.  This ISIS
cube file should be a level 2 (projected) image.  This file is used
to compute the radius of the planet/body using several methods.  The
input parameters MINRATIO and MAXRATIO are provided to compute inner
and outer rings of an annulus, respectively, centered on the feature
location (latitude, longitude).  These parameters are factors applied
to the radius of the feature as recorded in the match point file,
MATFROM, for the ground point.  If MINRATIO and MAXRATIO are set to
0.0, then only a single pixel value closest to the feature location
is read in and used as the radius of the planet/body.  If MINRATIO
and MAXRATIO are equivalent, but non-zero, then makeground will compute
an annulus the diagonal length of a pixel (resolution) and center the
annulus on the radius at MAXRATIO * radius.  This will generate an
annulus of at least a single pixel width of the desired length.  At
times, this will result in more, not less, pixels in the annulus than
specifying differing MINRATIO/MAXRATIO.  Note that the pixel data in
the DTM file must be either in KILOMETERS or METERS.  The value of
the CORE_UNIT keyword in the label of the DTM file must be either one
of these two values or the application is terminated.  (One can use
the "labels" program to set the value appropriately.)


PROGRAMMER:  Kris Becker, USGS, Flagstaff, Az

Input match file name
(No default extension)

NONE

Output match file name
(No default extension)

NONE

List of cube files where
*all* match points are
contained in
(no default extension)

NONE

Output ground point file
(no default extension)

NONE

DTM Cube file of radii
values used to create the
"radius" field in the
ground point file.
Must be level 2 image.

NONE

Value multiplied by the
radius of the feature
that defines the inner
ring of an annulus

1.0

Value multiplied by the
radius of the feature
that defines the outer
ring of an annulus

1.414

Provided so the user
can specify an alternative
directory to search for
cube files given in the
FROMLIST

--

Used to have the application
automatically select a ground
point from each set if one is
not already designated.  This
option selects the first
occuring level 2 image in the
set.

"YES"

ADDITIONAL NOTES:

Parm	Description
MATFROM	Input match file name. Contains the list of measured line/sample positions. It has fields containing a point id, image number, line and sample coordinate and point class, sub-pixel correlation and, diameter of measured feature.
MATTO	Output match file name. This file will be generated from the contents of the MATFROM file. The contents of this file will be identical to the MATFROM file except that any points on level 2 cubes (projected) will have their point class changed to "G" for ground point.
FROMLIST	ISIS cube list file name. Contains a list of image cubes, one file name per line. Each ISIS cube file in this list must have the IMAGE_NUMBER keyword in the label. Each match point read from the MATFROM file has an image identifier (IMAGE_NUMBER) associated with it. One of the ISIS cube files must contain this identifier.
GRNDTO	This output file will be created by the application. An entry for every measurement in the matchpoint file that is on a level 2 cube will be made in this file. Each entry is made up of some of the following fields: point id, diameter in kilometers of measure feature in reference cube, latitude of point, longitude of point, radius to center of planetary body in km, height in km of point, DTM file used to derive radius (or height) for this point, and a comment.
DTMFILE	This is an ISIS level 2 cube file, where each DN value represents the local radius for the point at that location. This file is used to compute the radius of the planet/body at the corresponding match point location.
MINRATIO	MINRATIO is a unitless value that is multiplied by the diameter of the match point stored in the MATTO match point file to define the inner ring of an annulus. makeground has the option of using an annulus (a donut-looking thing) around the center point of a feature from which to compute the radius of the planet/body. If the geometric location of the center of a pixel falls within the annulus, it is used to compute the average radius for that feature. If MINRATIO and MAXRATIO is 0, the degenerate case, then just the single pixel at the feature center is used as the radius value. If MINRATIO and MAXRATIO are equivalent but non-zero, then both MINRATIO and MAXRATIO are modified to result in the diagonal width of a pixel as the size of the annulus and it is centered on the original length.
MAXRATIO	MAXRATIO is a unitless value that is multiplied by the diameter of the match point stored in the MATTO match point file to define the outer ring of an annulus. makeground has the option of using an annulus (a donut-looking thing) around the center point of a feature from which to compute the radius of the planet/body. If the geometric location of the center of a pixel falls within the annulus, it is used to compute the average radius for that feature. If MINRATIO and MAXRATIO is 0, the degenerate case, then just the single pixel at the feature center is used as the radius value. If MINRATIO and MAXRATIO are equivalent but non-zero, then both MINRATIO and MAXRATIO are modified to result in the diagonal width of a pixel as the size of the annulus and it is centered on the original length.
ALTPATH	This parameter can be used to specify an alternative location of the ISIS cube files that correspond to each match point in MATTO and specified in FROMLIST. Note that this implies that files listed in FROMLIST may already have a directory path in the file. If the file is not found as it is extracted from FROMFILE, makeground will strip off the existing path and replace it with ALTPATH and attempt to open in in this location. If it is not found in either location, the application terminates abnormally.
SELECT	This parameter is provided to notify makeground that it may automatically select a ground point (SELECT="YES") if one does not exist for each match point set in MATFROM. Ground points have a "G" classification to designate them as a ground point. If one is not found for a given match point set, makeground will select the first occuring level 2 (i.e., the first projected cube) in the point set as sorted by image id. If SELECT="NO", then this procedure will not occur and match point sets must have at least one match point that is designated as a ground point or no ground point will be generated for the set.