Input file name. This parameter is input as:
INP=innam
where "innam" is the input file name.
Output and intermediate file names. This parameter is input as:
OUT=outnam
where:
"outnam" is the output file name, and
The size field is specified with four arguments,
SIZE=(a,b,c,d)
where:
a is the starting line number of the output picture.
b is the starting sample of the output picture.
c is the number of lines, and
d is the number of samples
For example, SIZE=(1,1,40,50)
would create an output picture of size 40 lines by 50 bytes.
The size field can be thought of as a window relative to the output
grid. The first two values offset the window down and to the right
causing the features in the image to move up and to the left.
SL can be used to specify the starting line of the output picture. This is actually a coordinate relative to the output grid, therefore, it offsets the output picture by (SL - 1.) The default for SL is 1.
SS can be used to specify the starting sample of the output picture. This is actually a coordinate relative to the output grid, therefore, it offsets the output picture by (SS - 1.) The default for SS is 1.
NL can be used in conjunction with NS in place of the SIZE parameter to specify the size of the output picture. It simply represents the number of lines for output. * See restrictions for more information
NS can be used in conjunction with NS in place of the SIZE parameter to specify the size of the output picture. It simply represents the number of bytes for output. * See restrictions for more information
This parameter has two valid keyword values: NOIN and ZNOIN.
NOIN means no interpolation. The default method (used when neither keyword
is specified) for computing the
DN values of the output picture is to use a bi-linear interpolation
on the four nearest neighbors in the input picture. With NOIN, the
value of the nearest point is simply used.
For example, say a point in the output picture was determined
to have come from point (R,P) in the input picture. Since R and P
are real values, we must somehow calculate a DN value for that
point. Take IR and IP as the truncated values. We then have
VAL1 VAL2
* *
(IR,IP) (IR,IP+1)
POINT
*
(R,P)
VAL3 VAL4
* *
(IR+1,IP) (IR+1,IP+1)
Here, POINT is the result of a bilinear interpolation using
VAL1, VAL2, VAL3, and VAL4.
If NOIN is specified, then POINT would be VAL1, the nearest
neighbor.
ZNOIN specifies that a four-point interpolation is done except
when one or more of the points used has a value equal to zero.
In that case the nearest method is used.
This allows preparation of sharp edges (no interpolation rolloff)
for mosaicking.
The format is obtained from the input image label.
the nah is number of grid cells horizontally, the number of tiepoints across is one larger (nah+1).
the nav is number of grid cells vertically, the number of tiepoints vertically is one larger (nav+1).
There are four real numbers for each tiepoint , the first two are the line-sample coordinate in the output, the second two are the line-sample coordinate in the input which is mapped to the point in the output. There must be (nah+1)*(nav+1) tiepoints (quadruple)s aligned in a perfectly horizontal and vertical grid.
A parameter data set containing the geom parameters. This file should have been written by a program which uses the XVP routines for writing parameter data sets. This is the most common means by which the parameters NAH, NAV, and TIEPOINT are passed.