lvpolyco(3)

LIBRARY ROUTINE
lvpolyco - Compute polynomial warp coefficients

LIBRARY CALL
#include "vinclude.h"
int
lvpolyco(x,y,xp,yp,xc,yc,n)
float *x,*y,*xp,*yp,*xc,*yc;
int n;

INPUT

x   X coordinates of source tiepoints

y   Y coordinates of source tiepoints

xp  X coordinates of target tiepoints

yp  Y coordinates of target tiepoints

n   number of tiepoints

OUTPUT

xc  X bipolynmial coefficients

yc  Y bipolynomial coefficients

    1 on success, 0 on failure.

MODIFICATIONS

DESCRIPTION
lvpolyco computes a set of bi-polynomial coefficients that tries to map the source tiepoints onto the target tiepoints. The order of the polynomials is controlled by the number of coordinate pairs in the source tiepoint arrays. The number of pairs must be the square of an integer. Thus a set of tiepoint arrays with 9 pairs will produce a coefficient matrix for a bi-quadratic polynomial.

The input arrays specify the tiepoint coordinates. Each input array should be of size N and of type FLOAT. The coordinates are stored as pairs of numbers, for example
     (x0,y0) (x1,y1) (x2,y2) (x3,y3) is stored in two float arrays as follows:
     x y
     -- --
     x0 y0
     x1 y1
     x2 y2
     x3 y3 The first input array (x) contains the X coordinates of the tie points in the original (source) image. The second input array (Y) contains the Y coordinates of the tie points in the original (source) image.

The output arrays contain the coefficients for the two polynomial mappings, one for the X coordinate and one for the Y coordinate.

SEE ALSO
vpolyco(1), intro(3), vipl(3), verror(3), vutils(3) vbilinco(1),vwarp(1)

RESTRICTIONS

AUTHOR
Scott Wilson

COPYRIGHT
Copyright 1991, University of New Mexico. All rights reserved.