1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
.help msisinit Dec98 "Image Interpolator Package"
.ih
NAME
msisinit -- initialize the sequential interpolant descriptor using user parameters
.ih
SYNOPSIS
include <math/iminterp.h>
msisinit (msi, interp_type, nsinc, nxincr, nyincr, pixfrac1, pixfrac2, badval)
.nf
pointer msi #O interpolant descriptor
int interp_type #I interpolant type
int nsinc #I sinc interpolant width in pixels
int nxincr,nyincr #I sinc look-up table resolution
real pixfrac1,pixfrac2 #I sinc or drizzle pixel fractions
real badval #I drizzle undefined pixel value
.fi
.ih
ARGUMENTS
.ls msi
Pointer to sequential interpolant descriptor.
.le
.ls interp_type
Interpolant type. The options are II_BINEAREST, II_BILINEAR, II_BIPOLY3,
II_BIPOLY5, II_BISPLINE3, II_BISINC, II_BILSINC, and II_BIDRIZZLE for the
nearest neighbour, linear, 3rd order polynomial, 5th order polynomial,
cubic spline, sinc, look-up table sinc, and drizzle interpolants respectively.
The interpolant type definitions are found in the package header file
math/iminterp.h.
.le
.ls nsinc
The sinc and look-up table sinc interpolant width in pixels. Nsinc is
rounded up internally to the nearest odd number.
.le
.ls nxincr, nyincr
The look-up table sinc resolution in x and y in number of entries. Nxincr = 10
implies a pixel resolution of 0.1 pixels in x, nxincr = 20 a pixel resolution
of 0.05 pixels in x, etc. The default value of nxincr and nyincr are 20 and 20
.le
.ls pixfrac1, pixfrac2
The look-up table sinc fractional pixel shifts in x and y if nincr = 1 in
which case -0.5 <= rparam[1/2] <= 0.5 , or the drizzle pixel fractions in
which case 0.0 <= rparam[1/2] <= 1.0.
.le
.ls badval
The undefined pixel value for the drizzle interpolant. Pixels within
the boundaries of the input image which do not overlap the input image
pixels are assigned a value of badval.
.le
.ih
DESCRIPTION
The interpolant descriptor is allocated and initialized. The pointer msi is
returned by MSISINIT.
.ih
NOTES
MSIINIT or MSISINIT must be called before using any other MSI routines.
.ih
SEE ALSO
msisinit, msifree
|
