/* Converts the buffer to cell and write it to disk */
static void write_fp_to_cell(int ofd, FCELL *buf)
{
CELL *cbuf;
int col;
cbuf = (CELL *) Rast_allocate_buf(CELL_TYPE);
for (col = 0; col < Rast_window_cols(); col++)
cbuf[col] = round_c(buf[col]);
Rast_put_row(ofd, cbuf, CELL_TYPE);
}
static int
write_pca(double **eigmat, int *inp_fd, char *out_basename,
int bands, int scale, int scale_min, int scale_max)
{
int i, j;
void *outbuf, *outptr;
double min = 0.;
double max = 0.;
double old_range = 0.;
double new_range = 0.;
int rows = Rast_window_rows();
int cols = Rast_window_cols();
int cell_mapsiz = Rast_cell_size(CELL_TYPE);
int dcell_mapsiz = Rast_cell_size(DCELL_TYPE);
DCELL *d_buf;
/* 2 passes for rescale. 1 pass for no rescale */
int PASSES = (scale) ? 2 : 1;
/* temporary row storage */
d_buf = (DCELL *) G_malloc(cols * sizeof(double));
/* allocate memory for output row buffer */
outbuf = (scale) ? Rast_allocate_buf(CELL_TYPE) :
Rast_allocate_buf(DCELL_TYPE);
if (!outbuf)
G_fatal_error(_("Unable to allocate memory for raster row"));
for (i = 0; i < bands; i++) {
char name[100];
int out_fd;
int pass;
sprintf(name, "%s.%d", out_basename, i + 1);
G_message(_("Transforming <%s>..."), name);
/* open a new file for output */
if (scale)
out_fd = Rast_open_c_new(name);
else {
out_fd = Rast_open_fp_new(name);
Rast_set_fp_type(DCELL_TYPE);
}
for (pass = 1; pass <= PASSES; pass++) {
void *rowbuf = NULL;
int row, col;
if (scale && (pass == PASSES)) {
G_message(_("Rescaling <%s> to range %d,%d..."),
name, scale_min, scale_max);
old_range = max - min;
new_range = (double)(scale_max - scale_min);
}
for (row = 0; row < rows; row++) {
void *rowptr;
G_percent(row, rows, 2);
/* reset d_buf */
for (col = 0; col < cols; col++)
d_buf[col] = 0.;
for (j = 0; j < bands; j++) {
RASTER_MAP_TYPE maptype =
Rast_get_map_type(inp_fd[j]);
/* don't assume each image is of the same type */
if (rowbuf)
G_free(rowbuf);
if (!(rowbuf = Rast_allocate_buf(maptype)))
G_fatal_error(_("Unable allocate memory for row buffer"));
Rast_get_row(inp_fd[j], rowbuf, row, maptype);
rowptr = rowbuf;
outptr = outbuf;
/* add into the output cell eigmat[i][j] * corresp cell
* of j-th band for current j */
for (col = 0; col < cols; col++) {
/* handle null cells */
if (Rast_is_null_value(rowptr, maptype)) {
if (scale) {
Rast_set_null_value(outptr, 1, CELL_TYPE);
outptr = G_incr_void_ptr(outptr, cell_mapsiz);
}
else {
Rast_set_null_value(outptr, 1, DCELL_TYPE);
outptr =
G_incr_void_ptr(outptr, dcell_mapsiz);
}
rowptr =
G_incr_void_ptr(rowptr,
Rast_cell_size(maptype));
continue;
}
/* corresp. cell of j-th band */
d_buf[col] +=
eigmat[i][j] * Rast_get_d_value(rowptr,
maptype);
/* the cell entry is complete */
if (j == (bands - 1)) {
if (scale && (pass == 1)) {
if ((row == 0) && (col == 0))
min = max = d_buf[0];
if (d_buf[col] < min)
min = d_buf[col];
if (d_buf[col] > max)
max = d_buf[col];
}
else if (scale) {
if (min == max) {
Rast_set_c_value(outptr, 1,
CELL_TYPE);
}
else {
/* map data to 0, (new_range-1) and then adding new_min */
CELL tmpcell =
round_c((new_range *
(d_buf[col] -
min) / old_range) +
scale_min);
Rast_set_c_value(outptr, tmpcell,
CELL_TYPE);
}
}
else { /* (!scale) */
Rast_set_d_value(outptr, d_buf[col],
DCELL_TYPE);
}
}
outptr = (scale) ?
G_incr_void_ptr(outptr, cell_mapsiz) :
G_incr_void_ptr(outptr, dcell_mapsiz);
rowptr =
G_incr_void_ptr(rowptr, Rast_cell_size(maptype));
}
} /* for j = 0 to bands */
if (pass == PASSES) {
if (scale)
Rast_put_row(out_fd, outbuf, CELL_TYPE);
else
Rast_put_row(out_fd, outbuf, DCELL_TYPE);
}
}
G_percent(row, rows, 2);
/* close output file */
if (pass == PASSES)
Rast_close(out_fd);
}
}
if (d_buf)
G_free(d_buf);
if (outbuf)
G_free(outbuf);
return 0;
}
