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-rw-r--r--gsl-1.9/wavelet/dwt.c390
1 files changed, 390 insertions, 0 deletions
diff --git a/gsl-1.9/wavelet/dwt.c b/gsl-1.9/wavelet/dwt.c
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+++ b/gsl-1.9/wavelet/dwt.c
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+/* wavelet/dwt.c
+ *
+ * Copyright (C) 2004 Ivo Alxneit
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/* function dwt_step is based on the public domain function pwt.c
+ * available from http://www.numerical-recipes.com
+ */
+
+#include <config.h>
+#include <gsl/gsl_errno.h>
+#include <gsl/gsl_wavelet.h>
+#include <gsl/gsl_wavelet2d.h>
+
+#define ELEMENT(a,stride,i) ((a)[(stride)*(i)])
+
+static int binary_logn (const size_t n);
+static void dwt_step (const gsl_wavelet * w, double *a, size_t stride, size_t n, gsl_wavelet_direction dir, gsl_wavelet_workspace * work);
+
+static int
+binary_logn (const size_t n)
+{
+ size_t ntest;
+ size_t logn = 0;
+ size_t k = 1;
+
+ while (k < n)
+ {
+ k *= 2;
+ logn++;
+ }
+
+ ntest = (1 << logn);
+
+ if (n != ntest)
+ {
+ return -1; /* n is not a power of 2 */
+ }
+
+ return logn;
+}
+
+static void
+dwt_step (const gsl_wavelet * w, double *a, size_t stride, size_t n,
+ gsl_wavelet_direction dir, gsl_wavelet_workspace * work)
+{
+ double ai, ai1;
+ size_t i, ii;
+ size_t jf;
+ size_t k;
+ size_t n1, ni, nh, nmod;
+
+ for (i = 0; i < work->n; i++)
+ {
+ work->scratch[i] = 0.0;
+ }
+
+ nmod = w->nc * n;
+ nmod -= w->offset; /* center support */
+
+ n1 = n - 1;
+ nh = n >> 1;
+
+ if (dir == gsl_wavelet_forward)
+ {
+ for (ii = 0, i = 0; i < n; i += 2, ii++)
+ {
+ ni = i + nmod;
+ for (k = 0; k < w->nc; k++)
+ {
+ jf = n1 & (ni + k);
+ work->scratch[ii] += w->h1[k] * ELEMENT (a, stride, jf);
+ work->scratch[ii + nh] += w->g1[k] * ELEMENT (a, stride, jf);
+ }
+ }
+ }
+ else
+ {
+ for (ii = 0, i = 0; i < n; i += 2, ii++)
+ {
+ ai = ELEMENT (a, stride, ii);
+ ai1 = ELEMENT (a, stride, ii + nh);
+ ni = i + nmod;
+ for (k = 0; k < w->nc; k++)
+ {
+ jf = (n1 & (ni + k));
+ work->scratch[jf] += (w->h2[k] * ai + w->g2[k] * ai1);
+ }
+ }
+ }
+
+ for (i = 0; i < n; i++)
+ {
+ ELEMENT (a, stride, i) = work->scratch[i];
+ }
+}
+
+int
+gsl_wavelet_transform (const gsl_wavelet * w,
+ double *data, size_t stride, size_t n,
+ gsl_wavelet_direction dir,
+ gsl_wavelet_workspace * work)
+{
+ size_t i;
+
+ if (work->n < n)
+ {
+ GSL_ERROR ("not enough workspace provided", GSL_EINVAL);
+ }
+
+ if (binary_logn (n) == -1)
+ {
+ GSL_ERROR ("n is not a power of 2", GSL_EINVAL);
+ }
+
+ if (n < 2)
+ {
+ return GSL_SUCCESS;
+ }
+
+ if (dir == gsl_wavelet_forward)
+ {
+ for (i = n; i >= 2; i >>= 1)
+ {
+ dwt_step (w, data, stride, i, dir, work);
+ }
+ }
+ else
+ {
+ for (i = 2; i <= n; i <<= 1)
+ {
+ dwt_step (w, data, stride, i, dir, work);
+ }
+ }
+
+ return GSL_SUCCESS;
+}
+
+int
+gsl_wavelet_transform_forward (const gsl_wavelet * w,
+ double *data, size_t stride, size_t n,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet_transform (w, data, stride, n, gsl_wavelet_forward, work);
+}
+
+int
+gsl_wavelet_transform_inverse (const gsl_wavelet * w,
+ double *data, size_t stride, size_t n,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet_transform (w, data, stride, n, gsl_wavelet_backward, work);
+}
+
+
+/* Leaving this out for now BJG */
+#if 0
+int
+gsl_dwt_vector (const gsl_wavelet * w, gsl_vector *v, gsl_wavelet_direction
+ dir, gsl_wavelet_workspace * work)
+{
+ return gsl_dwt (w, v->data, v->stride, v->size, dir, work);
+}
+#endif
+
+int
+gsl_wavelet2d_transform (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_direction dir,
+ gsl_wavelet_workspace * work)
+{
+ size_t i;
+
+ if (size1 != size2)
+ {
+ GSL_ERROR ("2d dwt works only with square matrix", GSL_EINVAL);
+ }
+
+ if (work->n < size1)
+ {
+ GSL_ERROR ("not enough workspace provided", GSL_EINVAL);
+ }
+
+ if (binary_logn (size1) == -1)
+ {
+ GSL_ERROR ("n is not a power of 2", GSL_EINVAL);
+ }
+
+ if (size1 < 2)
+ {
+ return GSL_SUCCESS;
+ }
+
+ if (dir == gsl_wavelet_forward)
+ {
+ for (i = 0; i < size1; i++) /* for every row j */
+ {
+ gsl_wavelet_transform (w, &ELEMENT(data, tda, i), 1, size1, dir, work);
+ }
+ for (i = 0; i < size2; i++) /* for every column j */
+ {
+ gsl_wavelet_transform (w, &ELEMENT(data, 1, i), tda, size2, dir, work);
+ }
+ }
+ else
+ {
+ for (i = 0; i < size2; i++) /* for every column j */
+ {
+ gsl_wavelet_transform (w, &ELEMENT(data, 1, i), tda, size2, dir, work);
+ }
+ for (i = 0; i < size1; i++) /* for every row j */
+ {
+ gsl_wavelet_transform (w, &ELEMENT(data, tda, i), 1, size1, dir, work);
+ }
+ }
+
+ return GSL_SUCCESS;
+}
+
+int
+gsl_wavelet2d_nstransform (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_direction dir,
+ gsl_wavelet_workspace * work)
+{
+ size_t i, j;
+
+ if (size1 != size2)
+ {
+ GSL_ERROR ("2d dwt works only with square matrix", GSL_EINVAL);
+ }
+
+ if (work->n < size1)
+ {
+ GSL_ERROR ("not enough workspace provided", GSL_EINVAL);
+ }
+
+ if (binary_logn (size1) == -1)
+ {
+ GSL_ERROR ("n is not a power of 2", GSL_EINVAL);
+ }
+
+ if (size1 < 2)
+ {
+ return GSL_SUCCESS;
+ }
+
+ if (dir == gsl_wavelet_forward)
+ {
+ for (i = size1; i >= 2; i >>= 1)
+ {
+ for (j = 0; j < i; j++) /* for every row j */
+ {
+ dwt_step (w, &ELEMENT(data, tda, j), 1, i, dir, work);
+ }
+ for (j = 0; j < i; j++) /* for every column j */
+ {
+ dwt_step (w, &ELEMENT(data, 1, j), tda, i, dir, work);
+ }
+ }
+ }
+ else
+ {
+ for (i = 2; i <= size1; i <<= 1)
+ {
+ for (j = 0; j < i; j++) /* for every column j */
+ {
+ dwt_step (w, &ELEMENT(data, 1, j), tda, i, dir, work);
+ }
+ for (j = 0; j < i; j++) /* for every row j */
+ {
+ dwt_step (w, &ELEMENT(data, tda, j), 1, i, dir, work);
+ }
+ }
+ }
+
+ return GSL_SUCCESS;
+}
+
+
+int
+gsl_wavelet2d_transform_forward (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_transform (w, data, tda, size1, size2, gsl_wavelet_forward, work);
+}
+
+int
+gsl_wavelet2d_transform_inverse (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_transform (w, data, tda, size1, size2, gsl_wavelet_backward, work);
+}
+
+int
+gsl_wavelet2d_nstransform_forward (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_nstransform (w, data, tda, size1, size2, gsl_wavelet_forward, work);
+}
+
+int
+gsl_wavelet2d_nstransform_inverse (const gsl_wavelet * w,
+ double *data, size_t tda, size_t size1,
+ size_t size2, gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_nstransform (w, data, tda, size1, size2, gsl_wavelet_backward, work);
+}
+
+
+int
+gsl_wavelet2d_transform_matrix (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_direction dir,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_transform (w, a->data,
+ a->tda, a->size1, a->size2,
+ dir, work);
+}
+
+int
+gsl_wavelet2d_transform_matrix_forward (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_transform (w, a->data,
+ a->tda, a->size1, a->size2,
+ gsl_wavelet_forward, work);
+}
+
+int
+gsl_wavelet2d_transform_matrix_inverse (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_transform (w, a->data,
+ a->tda, a->size1, a->size2,
+ gsl_wavelet_backward, work);
+}
+
+int
+gsl_wavelet2d_nstransform_matrix (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_direction dir,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_nstransform (w, a->data,
+ a->tda, a->size1, a->size2,
+ dir, work);
+}
+
+int
+gsl_wavelet2d_nstransform_matrix_forward (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_nstransform (w, a->data,
+ a->tda, a->size1, a->size2,
+ gsl_wavelet_forward, work);
+}
+
+int
+gsl_wavelet2d_nstransform_matrix_inverse (const gsl_wavelet * w,
+ gsl_matrix * a,
+ gsl_wavelet_workspace * work)
+{
+ return gsl_wavelet2d_nstransform (w, a->data,
+ a->tda, a->size1, a->size2,
+ gsl_wavelet_backward, work);
+}
+
+
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