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@@ -0,0 +1,530 @@
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+
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+/***********************************************************************
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+
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+ crs3d.c
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+
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+ written by: Markus Metz
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+
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+ based on crs.c - Center for Remote Sensing rectification routines
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+
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+************************************************************************/
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+
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+#include <stdio.h>
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+#include <string.h>
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+#include <stdlib.h>
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+#include <math.h>
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+#include <limits.h>
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+
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+#include <grass/gis.h>
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+#include <grass/imagery.h>
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+
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+#include "crs.h"
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+
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+/* STRUCTURE FOR USE INTERNALLY WITH THESE FUNCTIONS. THESE FUNCTIONS EXPECT
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+ SQUARE MATRICES SO ONLY ONE VARIABLE IS GIVEN (N) FOR THE MATRIX SIZE */
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+
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+struct MATRIX
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+{
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+ int n; /* SIZE OF THIS MATRIX (N x N) */
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+ double *v;
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+};
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+
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+/* CALCULATE OFFSET INTO ARRAY BASED ON R/C */
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+
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+#define M(row,col) m->v[(((row)-1)*(m->n))+(col)-1]
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+
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+#define MSUCCESS 1 /* SUCCESS */
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+#define MNPTERR 0 /* NOT ENOUGH POINTS */
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+#define MUNSOLVABLE -1 /* NOT SOLVABLE */
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+#define MMEMERR -2 /* NOT ENOUGH MEMORY */
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+#define MPARMERR -3 /* PARAMETER ERROR */
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+#define MINTERR -4 /* INTERNAL ERROR */
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+
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+/***********************************************************************
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+
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+ FUNCTION PROTOTYPES FOR STATIC (INTERNAL) FUNCTIONS
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+
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+************************************************************************/
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+
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+static int calccoef(struct Control_Points_3D *, double *, double *, double *, int);
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+static int calcls(struct Control_Points_3D *, struct MATRIX *,
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+ double *, double *, double *,
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+ double *, double *, double *);
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+static int exactdet(struct Control_Points_3D *, struct MATRIX *,
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+ double *, double *, double *,
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+ double *, double *, double *);
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+static int solvemat(struct MATRIX *, double *, double *, double *,
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+ double *, double *, double *);
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+static double term(int, double, double, double);
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+
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+/***********************************************************************
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+
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+ TRANSFORM A SINGLE COORDINATE PAIR.
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+
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+************************************************************************/
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+
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+int CRS_georef_3d(double e1, /* EASTING TO BE TRANSFORMED */
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+ double n1, /* NORTHING TO BE TRANSFORMED */
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+ double z1, /* HEIGHT TO BE TRANSFORMED */
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+ double *e, /* EASTING, TRANSFORMED */
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+ double *n, /* NORTHING, TRANSFORMED */
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+ double *z, /* HEIGHT, TRANSFORMED */
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+ double E[], /* EASTING COEFFICIENTS */
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+ double N[], /* NORTHING COEFFICIENTS */
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+ double Z[], /* HEIGHT COEFFICIENTS */
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+ int order /* ORDER OF TRANSFORMATION TO BE PERFORMED, MUST MATCH THE
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+ ORDER USED TO CALCULATE THE COEFFICIENTS */
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+ )
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+{
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+ double e2, n2, z2, en, ez, nz,
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+ e3, n3, z3, e2n, e2z, en2, ez2, n2z, nz2, enz;
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+
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+ switch (order) {
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+ case 1:
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+ *e = E[0] + E[1] * e1 + E[2] * n1 + E[3] * z1;
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+ *n = N[0] + N[1] * e1 + N[2] * n1 + N[3] * z1;
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+ *z = Z[0] + Z[1] * e1 + Z[2] * n1 + Z[3] * z1;
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+ break;
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+
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+ case 2:
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+ e2 = e1 * e1;
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+ en = e1 * n1;
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+ ez = e1 * z1;
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+ n2 = n1 * n1;
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+ nz = n1 * z1;
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+ z2 = z1 * z1;
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+
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+ *e = E[0] + E[1] * e1 + E[2] * n1 + E[3] * z1 +
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+ E[4] * e2 + E[5] * en + E[6] * ez + E[7] * n2 + E[8] * nz + E[9] * z2;
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+ *n = N[0] + N[1] * e1 + N[2] * n1 + N[3] * z1 +
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+ N[4] * e2 + N[5] * en + N[6] * ez + N[7] * n2 + N[8] * nz + N[9] * z2;
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+ *z = Z[0] + Z[1] * e1 + Z[2] * n1 + Z[3] * z1 +
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+ Z[4] * e2 + Z[5] * en + Z[6] * ez + Z[7] * n2 + Z[8] * nz + Z[9] * z2;
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+ break;
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+
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+ case 3:
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+ e2 = e1 * e1;
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+ en = e1 * n1;
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+ ez = e1 * z1;
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+ n2 = n1 * n1;
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+ nz = n1 * z1;
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+ z2 = z1 * z1;
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+
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+ e3 = e1 * e2;
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+ e2n = e2 * n1;
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+ e2z = e2 * z1;
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+ en2 = e1 * n2;
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+ enz = e1 * n1 * z1;
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+ ez2 = e1 * z2;
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+ n3 = n1 * n2;
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+ n2z = n2 * z1;
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+ nz2 = n1 * z2;
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+ z3 = z1 * z2;
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+
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+ *e = E[0] + E[1] * e1 + E[2] * n1 + E[3] * z1 +
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+ E[4] * e2 + E[5] * en + E[6] * ez + E[7] * n2 + E[8] * nz + E[9] * z2 +
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+ E[10] * e3 + E[11] * e2n + E[12] * e2z + E[13] * en2 + E[14] * enz +
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+ E[15] * ez2 + E[16] * n3 + E[17] * n2z + E[18] * nz2 + E[19] * z3;
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+ *n = N[0] + N[1] * e1 + N[2] * n1 + N[3] * z1 +
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+ N[4] * e2 + N[5] * en + N[6] * ez + N[7] * n2 + N[8] * nz + N[9] * z2 +
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+ N[10] * e3 + N[11] * e2n + N[12] * e2z + N[13] * en2 + N[14] * enz +
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+ N[15] * ez2 + N[16] * n3 + N[17] * n2z + N[18] * nz2 + N[19] * z3;
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+ *z = Z[0] + Z[1] * e1 + Z[2] * n1 + Z[3] * z1 +
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+ Z[4] * e2 + Z[5] * en + Z[6] * ez + Z[7] * n2 + Z[8] * nz + Z[9] * z2 +
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+ Z[10] * e3 + Z[11] * e2n + Z[12] * e2z + Z[13] * en2 + Z[14] * enz +
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+ Z[15] * ez2 + Z[16] * n3 + Z[17] * n2z + Z[18] * nz2 + Z[19] * z3;
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+ break;
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+
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+ default:
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+ return MPARMERR;
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+ }
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+
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+ return MSUCCESS;
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+}
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+
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+/***********************************************************************
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+
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+ COMPUTE THE FORWARD AND BACKWARD GEOREFFERENCING COEFFICIENTS
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+ BASED ON A SET OF CONTROL POINTS
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+
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+************************************************************************/
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+
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+int CRS_compute_georef_equations_3d(struct Control_Points_3D *cp,
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+ double E12[], double N12[], double Z12[],
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+ double E21[], double N21[], double Z21[],
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+ int order)
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+{
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+ double *tempptr;
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+ int status;
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+
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+ /*
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+ if (order < 1 || order > MAXORDER)
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+ return MPARMERR;
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+ */
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+
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+ /* CALCULATE THE FORWARD TRANSFORMATION COEFFICIENTS */
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+
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+ status = calccoef(cp, E12, N12, Z12, order);
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+
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+ if (status != MSUCCESS)
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+ return status;
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+
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+ /* SWITCH THE 1 AND 2 EASTING, NORTHING, AND HEIGHT ARRAYS */
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+
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+ tempptr = cp->e1;
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+ cp->e1 = cp->e2;
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+ cp->e2 = tempptr;
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+ tempptr = cp->n1;
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+ cp->n1 = cp->n2;
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+ cp->n2 = tempptr;
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+ tempptr = cp->z1;
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+ cp->z1 = cp->z2;
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+ cp->z2 = tempptr;
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+
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+ /* CALCULATE THE BACKWARD TRANSFORMATION COEFFICIENTS */
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+
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+ status = calccoef(cp, E21, N21, Z21, order);
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+
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+ /* SWITCH THE 1 AND 2 EASTING, NORTHING, AND HEIGHT ARRAYS BACK */
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+
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+ tempptr = cp->e1;
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+ cp->e1 = cp->e2;
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+ cp->e2 = tempptr;
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+ tempptr = cp->n1;
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+ cp->n1 = cp->n2;
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+ cp->n2 = tempptr;
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+ tempptr = cp->z1;
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+ cp->z1 = cp->z2;
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+ cp->z2 = tempptr;
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+
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+ return status;
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+}
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+
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+/***********************************************************************
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+
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+ COMPUTE THE GEOREFFERENCING COEFFICIENTS
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+ BASED ON A SET OF CONTROL POINTS
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+
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+************************************************************************/
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+
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+static int calccoef(struct Control_Points_3D *cp,
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+ double E[], double N[], double Z[],
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+ int order)
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+{
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+ struct MATRIX m;
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+ double *a;
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+ double *b;
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+ double *c;
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+ int numactive; /* NUMBER OF ACTIVE CONTROL POINTS */
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+ int status, i;
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+
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+ /* CALCULATE THE NUMBER OF VALID CONTROL POINTS */
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+
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+ for (i = numactive = 0; i < cp->count; i++) {
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+ if (cp->status[i] > 0)
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+ numactive++;
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+ }
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+
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+ /* CALCULATE THE MINIMUM NUMBER OF CONTROL POINTS NEEDED TO DETERMINE
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+ A TRANSFORMATION OF THIS ORDER */
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+
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+ /*
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+ 2D 3D
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+ 1st order: 3 4
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+ 2nd order: 6 10
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+ 3rd order: 10 20
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+ */
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+
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+ if (order == 1)
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+ m.n = 4;
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+ else if (order == 2)
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+ m.n = 10;
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+ else if (order == 3)
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+ m.n = 20;
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+
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+ if (numactive < m.n)
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+ return MNPTERR;
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+
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+ /* INITIALIZE MATRIX */
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+
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+ m.v = G_calloc(m.n * m.n, sizeof(double));
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+ a = G_calloc(m.n, sizeof(double));
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+ b = G_calloc(m.n, sizeof(double));
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+ c = G_calloc(m.n, sizeof(double));
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+
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+ if (numactive == m.n)
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+ status = exactdet(cp, &m, a, b, c, E, N, Z);
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+ else
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+ status = calcls(cp, &m, a, b, c, E, N, Z);
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+
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+ G_free(m.v);
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+ G_free(a);
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+ G_free(b);
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+ G_free(c);
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+
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+ return status;
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+}
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+
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+/***********************************************************************
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+
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+ CALCULATE THE TRANSFORMATION COEFFICIENTS WITH EXACTLY THE MINIMUM
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+ NUMBER OF CONTROL POINTS REQUIRED FOR THIS TRANSFORMATION.
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+
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+************************************************************************/
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+
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+static int exactdet(struct Control_Points_3D *cp, struct MATRIX *m,
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+ double a[], double b[], double c[],
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+ double E[], /* EASTING COEFFICIENTS */
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+ double N[], /* NORTHING COEFFICIENTS */
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+ double Z[] /* HEIGHT COEFFICIENTS */
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+ )
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+{
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+ int pntnow, currow, j;
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+
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+ currow = 1;
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+ for (pntnow = 0; pntnow < cp->count; pntnow++) {
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+ if (cp->status[pntnow] > 0) {
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+ /* POPULATE MATRIX M */
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+
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+ for (j = 1; j <= m->n; j++)
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+ M(currow, j) = term(j, cp->e1[pntnow], cp->n1[pntnow], cp->z1[pntnow]);
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+
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+ /* POPULATE MATRIX A AND B */
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+
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+ a[currow - 1] = cp->e2[pntnow];
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+ b[currow - 1] = cp->n2[pntnow];
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+ c[currow - 1] = cp->z2[pntnow];
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+
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+ currow++;
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+ }
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+ }
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+
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+ if (currow - 1 != m->n)
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+ return MINTERR;
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+
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+ return solvemat(m, a, b, c, E, N, Z);
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+}
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+
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+/***********************************************************************
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+
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+ CALCULATE THE TRANSFORMATION COEFFICIENTS WITH MORE THAN THE MINIMUM
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+ NUMBER OF CONTROL POINTS REQUIRED FOR THIS TRANSFORMATION. THIS
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+ ROUTINE USES THE LEAST SQUARES METHOD TO COMPUTE THE COEFFICIENTS.
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+
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+************************************************************************/
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+
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+static int calcls(struct Control_Points_3D *cp, struct MATRIX *m,
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+ double a[], double b[], double c[],
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+ double E[], /* EASTING COEFFICIENTS */
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+ double N[], /* NORTHING COEFFICIENTS */
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+ double Z[] /* HEIGHT COEFFICIENTS */
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+ )
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+{
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+ int i, j, n, numactive = 0;
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+
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+ /* INITIALIZE THE UPPER HALF OF THE MATRIX AND THE TWO COLUMN VECTORS */
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+
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+ for (i = 1; i <= m->n; i++) {
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+ for (j = i; j <= m->n; j++)
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+ M(i, j) = 0.0;
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+ a[i - 1] = b[i - 1] = c[i - 1] = 0.0;
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+ }
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+
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+ /* SUM THE UPPER HALF OF THE MATRIX AND THE COLUMN VECTORS ACCORDING TO
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+ THE LEAST SQUARES METHOD OF SOLVING OVER DETERMINED SYSTEMS */
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+
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+ for (n = 0; n < cp->count; n++) {
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+ if (cp->status[n] > 0) {
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+ numactive++;
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+ for (i = 1; i <= m->n; i++) {
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+ for (j = i; j <= m->n; j++)
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+ M(i, j) += term(i, cp->e1[n], cp->n1[n], cp->z1[n]) *
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+ term(j, cp->e1[n], cp->n1[n], cp->z1[n]);
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+
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+ a[i - 1] += cp->e2[n] * term(i, cp->e1[n], cp->n1[n], cp->z1[n]);
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+ b[i - 1] += cp->n2[n] * term(i, cp->e1[n], cp->n1[n], cp->z1[n]);
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+ c[i - 1] += cp->z2[n] * term(i, cp->e1[n], cp->n1[n], cp->z1[n]);
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+ }
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+ }
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+ }
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+
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+ if (numactive <= m->n)
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+ return MINTERR;
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+
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+ /* TRANSPOSE VALUES IN UPPER HALF OF M TO OTHER HALF */
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+
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+ for (i = 2; i <= m->n; i++)
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+ for (j = 1; j < i; j++)
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+ M(i, j) = M(j, i);
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+
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+ return solvemat(m, a, b, c, E, N, Z);
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+}
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+
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+/***********************************************************************
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+
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+ CALCULATE THE X/Y TERM BASED ON THE TERM NUMBER
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+
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+ ORDER\TERM 1 2 3 4 5 6 7 8 9 10
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+ 1 e0n0z0 e1n0z0 e0n1z0 e0n0z1
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+ 2 e0n0z0 e1n0z0 e0n1z0 e0n0z1 e2n0z0 e1n1z0 e1n0z1 e0n2z0 e0n1z1 e0n0z2
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+ 3 e0n0z0 e1n0z0 e0n1z0 e0n0z1 e2n0z0 e1n1z0 e1n0z1 e0n2z0 e0n1z1 e0n0z2
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+
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|
+ ORDER\TERM 11 12 13 14 15 16 17 18 19 20
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|
|
+ 3 e3n0z0 e2n1z0 e2n0z1 e1n2z0 e1n1z1 e1n0z2 e0n3z0 e0n2z1 e0n1z2 e0n0z3
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+
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|
|
+************************************************************************/
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|
|
+
|
|
|
+static double term(int term, double e, double n, double z)
|
|
|
+{
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|
|
+ switch (term) {
|
|
|
+ /* 1st order */
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|
|
+ case 1:
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|
|
+ return 1.0;
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|
|
+ case 2:
|
|
|
+ return e;
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|
|
+ case 3:
|
|
|
+ return n;
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|
|
+ case 4:
|
|
|
+ return z;
|
|
|
+ /* 2nd order */
|
|
|
+ case 5:
|
|
|
+ return e * e;
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|
|
+ case 6:
|
|
|
+ return e * n;
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|
|
+ case 7:
|
|
|
+ return e * z;
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|
|
+ case 8:
|
|
|
+ return n * n;
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|
|
+ case 9:
|
|
|
+ return n * z;
|
|
|
+ case 10:
|
|
|
+ return z * z;
|
|
|
+ /* 3rd order */
|
|
|
+ case 11:
|
|
|
+ return e * e * e;
|
|
|
+ case 12:
|
|
|
+ return e * e * n;
|
|
|
+ case 13:
|
|
|
+ return e * e * z;
|
|
|
+ case 14:
|
|
|
+ return e * n * n;
|
|
|
+ case 15:
|
|
|
+ return e * n * z;
|
|
|
+ case 16:
|
|
|
+ return e * z * z;
|
|
|
+ case 17:
|
|
|
+ return n * n * n;
|
|
|
+ case 18:
|
|
|
+ return n * n * z;
|
|
|
+ case 19:
|
|
|
+ return n * z * z;
|
|
|
+ case 20:
|
|
|
+ return z * z * z;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0.0;
|
|
|
+}
|
|
|
+
|
|
|
+/***********************************************************************
|
|
|
+
|
|
|
+ SOLVE FOR THE 'E', 'N' AND 'Z' COEFFICIENTS BY USING A
|
|
|
+ SOMEWHAT MODIFIED GAUSSIAN ELIMINATION METHOD.
|
|
|
+
|
|
|
+ | M11 M12 ... M1n | | E0 | | a0 |
|
|
|
+ | M21 M22 ... M2n | | E1 | = | a1 |
|
|
|
+ | . . . . | | . | | . |
|
|
|
+ | Mn1 Mn2 ... Mnn | | En-1 | | an-1 |
|
|
|
+
|
|
|
+ ,
|
|
|
+
|
|
|
+ | M11 M12 ... M1n | | N0 | | b0 |
|
|
|
+ | M21 M22 ... M2n | | N1 | = | b1 |
|
|
|
+ | . . . . | | . | | . |
|
|
|
+ | Mn1 Mn2 ... Mnn | | Nn-1 | | bn-1 |
|
|
|
+
|
|
|
+ and
|
|
|
+
|
|
|
+ | M11 M12 ... M1n | | Z0 | | c0 |
|
|
|
+ | M21 M22 ... M2n | | Z1 | = | c1 |
|
|
|
+ | . . . . | | . | | . |
|
|
|
+ | Mn1 Mn2 ... Mnn | | Zn-1 | | cn-1 |
|
|
|
+
|
|
|
+************************************************************************/
|
|
|
+
|
|
|
+static int solvemat(struct MATRIX *m, double a[], double b[], double c[],
|
|
|
+ double E[], double N[], double Z[])
|
|
|
+{
|
|
|
+ int i, j, i2, j2, imark;
|
|
|
+ double factor, temp;
|
|
|
+ double pivot; /* ACTUAL VALUE OF THE LARGEST PIVOT CANDIDATE */
|
|
|
+
|
|
|
+ for (i = 1; i <= m->n; i++) {
|
|
|
+ j = i;
|
|
|
+
|
|
|
+ /* find row with largest magnitude value for pivot value */
|
|
|
+
|
|
|
+ pivot = M(i, j);
|
|
|
+ imark = i;
|
|
|
+ for (i2 = i + 1; i2 <= m->n; i2++) {
|
|
|
+ temp = fabs(M(i2, j));
|
|
|
+ if (temp > fabs(pivot)) {
|
|
|
+ pivot = M(i2, j);
|
|
|
+ imark = i2;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ /* if the pivot is very small then the points are nearly co-linear */
|
|
|
+ /* co-linear points result in an undefined matrix, and nearly */
|
|
|
+ /* co-linear points results in a solution with rounding error */
|
|
|
+
|
|
|
+ if (pivot == 0.0)
|
|
|
+ return MUNSOLVABLE;
|
|
|
+
|
|
|
+ /* if row with highest pivot is not the current row, switch them */
|
|
|
+
|
|
|
+ if (imark != i) {
|
|
|
+ for (j2 = 1; j2 <= m->n; j2++) {
|
|
|
+ temp = M(imark, j2);
|
|
|
+ M(imark, j2) = M(i, j2);
|
|
|
+ M(i, j2) = temp;
|
|
|
+ }
|
|
|
+
|
|
|
+ temp = a[imark - 1];
|
|
|
+ a[imark - 1] = a[i - 1];
|
|
|
+ a[i - 1] = temp;
|
|
|
+
|
|
|
+ temp = b[imark - 1];
|
|
|
+ b[imark - 1] = b[i - 1];
|
|
|
+ b[i - 1] = temp;
|
|
|
+
|
|
|
+ temp = c[imark - 1];
|
|
|
+ c[imark - 1] = c[i - 1];
|
|
|
+ c[i - 1] = temp;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* compute zeros above and below the pivot, and compute
|
|
|
+ values for the rest of the row as well */
|
|
|
+
|
|
|
+ for (i2 = 1; i2 <= m->n; i2++) {
|
|
|
+ if (i2 != i) {
|
|
|
+ factor = M(i2, j) / pivot;
|
|
|
+ for (j2 = j; j2 <= m->n; j2++)
|
|
|
+ M(i2, j2) -= factor * M(i, j2);
|
|
|
+ a[i2 - 1] -= factor * a[i - 1];
|
|
|
+ b[i2 - 1] -= factor * b[i - 1];
|
|
|
+ c[i2 - 1] -= factor * c[i - 1];
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ /* SINCE ALL OTHER VALUES IN THE MATRIX ARE ZERO NOW, CALCULATE THE
|
|
|
+ COEFFICIENTS BY DIVIDING THE COLUMN VECTORS BY THE DIAGONAL VALUES. */
|
|
|
+
|
|
|
+ for (i = 1; i <= m->n; i++) {
|
|
|
+ E[i - 1] = a[i - 1] / M(i, i);
|
|
|
+ N[i - 1] = b[i - 1] / M(i, i);
|
|
|
+ Z[i - 1] = c[i - 1] / M(i, i);
|
|
|
+ }
|
|
|
+
|
|
|
+ return MSUCCESS;
|
|
|
+}
|