URL:
https://svn.lrde.epita.fr/svn/oln/trunk/milena
ChangeLog:
2007-09-06 Simon Nivault <simon.nivault(a)lrde.epita.fr>
Move fast gaussian out of sandbox
* sandbox/nivault/fast_gaussian.hh: Rename as...
* mln/linear/fast_gaussian.hh: ...this.
Fix.
trunk/milena/mln/linear/fast_gaussian.hh | 318 +++++++++++++++++++++++++++++++
1 file changed, 318 insertions(+)
Index: trunk/milena/mln/linear/fast_gaussian.hh
===================================================================
--- trunk/milena/mln/linear/fast_gaussian.hh (revision 0)
+++ trunk/milena/mln/linear/fast_gaussian.hh (revision 1077)
@@ -0,0 +1,318 @@
+// Copyright (C) 2001, 2002, 2003, 2004 EPITA Research and Development Laboratory
+//
+// This file is part of the Olena Library. This library is free
+// software; you can redistribute it and/or modify it under the terms
+// of the GNU General Public License version 2 as published by the
+// Free Software Foundation.
+//
+// This library 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 library; see the file COPYING. If not, write to
+// the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+// Boston, MA 02110-1301, USA.
+//
+// As a special exception, you may use this file as part of a free
+// software library without restriction. Specifically, if other files
+// instantiate templates or use macros or inline functions from this
+// file, or you compile this file and link it with other files to
+// produce an executable, this file does not by itself cause the
+// resulting executable to be covered by the GNU General Public
+// License. This exception does not however invalidate any other
+// reasons why the executable file might be covered by the GNU General
+// Public License.
+
+#ifndef MLN_LINEAR_FAST_GAUSSIAN_HH__
+# define MLN_LINEAR_FAST_GAUSSIAN_HH__
+
+/*! \file mln/linear/fast_gaussian.hh
+ *
+ * \brief Fast gaussian.
+ */
+
+# include <mln/core/concept/image.hh>
+# include <mln/level/paste.hh>
+
+
+
+namespace mln
+{
+
+ namespace linear
+ {
+
+ /*! Fast gaussian of an image \p input
+ *
+ * \pre output.domain = input.domain
+ */
+ template <class I, class O>
+ void
+ gaussian(const Image<I>& input, float sigma,
+ Image<O>& output)
+
+# ifndef MLN_INCLUDE_ONLY
+
+ namespace impl
+ {
+
+ struct recursivefilter_coef_
+ {
+
+ /*!
+ ** \brief Constructor.
+ */
+ recursivefilter_coef_(float a0, float a1,
+ float b0, float b1,
+ float c0, float c1,
+ float w0, float w1,
+ float s);
+ std::vector<float> n, d, nm, dm;
+ float sumA, sumC;
+ };
+
+ recursivefilter_coef_::recursivefilter_coef_(float a0, float a1,
+ float b0, float b1,
+ float c0, float c1,
+ float w0, float w1,
+ float s)
+ {
+ n.reserve(5);
+ d.reserve(5);
+ nm.reserve(5);
+ dm.reserve(5);
+
+ b0 /= s;
+ b1 /= s;
+ w0 /= s;
+ w1 /= s;
+
+ float sin0 = sin(w0);
+ float sin1 = sin(w1);
+ float cos0 = cos(w0);
+ float cos1 = cos(w1);
+
+ sumA =
+ (2.0 * a1 * exp( b0 ) * cos0 * cos0 - a0 * sin0 * exp( 2.0 * b0 )
+ + a0 * sin0 - 2.0 * a1 * exp( b0 )) /
+ (( 2.0 * cos0 * exp( b0 ) - exp( 2.0 * b0 ) - 1 ) * sin0);
+
+ sumC =
+ (2.0 * c1 * exp( b1 ) * cos1 * cos1 - c0 * sin1 * exp( 2.0 * b1 )
+ + c0 * sin1 - 2.0 * c1 * exp( b1 ))
+ / (( 2.0 * cos1 * exp( b1 ) - exp( 2.0 * b1 ) - 1 ) * sin1);
+
+ a0 /= (sumA + sumC);
+ a1 /= (sumA + sumC);
+ c0 /= (sumA + sumC);
+ c1 /= (sumA + sumC);
+
+ n[3] =
+ exp( -b1 - 2*b0 ) * (c1 * sin1 - cos1 * c0) +
+ exp( -b0 - 2*b1 ) * (a1 * sin0 - cos0 * a0);
+ n[2] =
+ 2 * exp(-b0 - b1) * ((a0 + c0) * cos1 * cos0 -
+ cos1 * a1 * sin0 -
+ cos0 * c1 * sin1) +
+ c0 * exp(-2 * b0) + a0 * exp(-2 * b1);
+ n[1] =
+ exp(-b1) * (c1 * sin1 - (c0 + 2*a0) * cos1) +
+ exp(-b0) * (a1 * sin0 - (2*c0 + a0) * cos0);
+ n[0] =
+ a0 + c0;
+
+ d[4] = exp(-2 * b0 - 2 * b1);
+ d[3] =
+ -2 * cos0 * exp(-b0 - 2*b1) -
+ 2 * cos1 * exp(-b1 - 2*b0);
+ d[2] =
+ 4 * cos1 * cos0 * exp(-b0 - b1) +
+ exp(-2*b1) + exp(-2*b0);
+ d[1] =
+ -2*exp(-b1) * cos1 - 2 * exp(-b0) * cos0;
+
+ for (unsigned i = 1; i <= 3; ++i)
+ {
+ dm[i] = d[i];
+ nm[i] = n[i] - d[i] * n[0];
+ }
+ dm[4] = d[4];
+ nm[4] = -d[4] * n[0];
+ }
+
+
+
+ template <class WorkType, class I>
+ void
+ recursivefilter_(I& ima,
+ const recursivefilter_coef_& c,
+ const mln_point(I)& start,
+ const mln_point(I)& finish,
+ int len,
+ const mln_dpoint(I)& d)
+ {
+ std::vector<WorkType> tmp1(len);
+ std::vector<WorkType> tmp2(len);
+
+ // The fourth degree approximation implies to have a special
+ // look on the four first points we consider that there is
+ // no signal before 0 (to be discussed)
+
+ // --
+ // Causal part
+
+ tmp1[0] =
+ c.n[0] * ima(start);
+
+ tmp1[1] =
+ c.n[0] * ima(start + d)
+ + c.n[1] * ima(start)
+ - c.d[1] * tmp1[0];
+
+ tmp1[2] =
+ c.n[0] * ima(start + d + d)
+ + c.n[1] * ima(start + d)
+ + c.n[2] * ima(start)
+ - c.d[1] * tmp1[1]
+ - c.d[2] * tmp1[0];
+
+ tmp1[3] =
+ c.n[0] * ima(start + d + d + d)
+ + c.n[1] * ima(start + d + d)
+ + c.n[2] * ima(start + d)
+ + c.n[3] * ima(start)
+ - c.d[1] * tmp1[2] - c.d[2]*tmp1[1]
+ - c.d[3] * tmp1[0];
+
+ mln_point(I) current(start + d + d + d + d);
+ for (mln_coord(I) i = 4; i < len; ++i)
+ {
+ tmp1[i] =
+ c.n[0] * ima(current)
+ + c.n[1] * ima(current - d)
+ + c.n[2] * ima(current - d - d)
+ + c.n[3] * ima(current - d - d - d)
+ - c.d[1] * tmp1[i - 1] - c.d[2]*tmp1[i - 2]
+ - c.d[3] * tmp1[i - 3] - c.d[4]*tmp1[i - 4];
+ current = current + d;
+ }
+
+ // Non causal part
+
+ tmp2[len - 1] = 0;
+
+ tmp2[len - 2] =
+ c.nm[1] * ima(finish);
+
+ tmp2[len - 3] =
+ c.nm[1] * ima(finish - d)
+ + c.nm[2] * ima(finish)
+ - c.dm[1] * tmp2[len-2];
+
+ tmp2[len - 4] =
+ c.nm[1] * ima(finish - d - d)
+ + c.nm[2] * ima(finish - d)
+ + c.nm[3] * ima(finish)
+ - c.dm[1] * tmp2[len-3]
+ - c.dm[2] * tmp2[len-2];
+
+ current = finish - d - d - d ;
+
+ for (int i = len - 5; i >= 0; --i)
+ {
+ tmp2[i] =
+ c.nm[1] * ima(current)
+ + c.nm[2] * ima(current + d)
+ + c.nm[3] * ima(current + d + d)
+ + c.nm[4] * ima(current + d + d + d)
+ - c.dm[1] * tmp2[i+1] - c.dm[2]*tmp2[i+2]
+ - c.dm[3] * tmp2[i+3] - c.dm[4]*tmp2[i+4];
+ current = current - d;
+ }
+
+ // Combine results from causal and non-causal parts.
+
+ current = start;
+ for (int i = 0; i < len; ++i)
+ {
+ ima(current) = tmp1[i] + tmp2[i];
+ current = current + d;
+ }
+ }
+
+
+ template <class I, class F>
+ void
+ gaussian_(Image<I>& img_, const F& coef)
+ {
+ I& img = exact(img_);
+
+ // Apply on rows.
+ for (int j = 0; j < geom::ncols(img); ++j)
+ recursivefilter_<float>(img, coef,
+ make::point2d(-img.border(), j),
+ make::point2d(geom::nrows(img) - 1 + img.border(), j),
+ geom::nrows(img) + 2 * img.border(),
+ make::dpoint2d(1, 0));
+
+ // Apply on columns.
+ for (int i = 0; i < geom::nrows(img); ++i)
+ recursivefilter_<float>(img, coef,
+ make::point2d(i, -img.border()),
+ make::point2d(i, geom::ncols(img) - 1 + img.border()),
+ geom::ncols(img) + 2 * img.border(),
+ make::dpoint2d(0, 1));
+
+ }
+
+
+ template <class I, class F, class O>
+ void
+ gaussian_common_(const Image<I>& in,
+ const F& coef,
+ float sigma,
+ Image<O>& out)
+ {
+ mln_ch_value(O, float) work_img(exact(in).domain());
+ level::paste(in, work_img);
+
+ // On tiny sigma, Derich algorithm doesn't work.
+ // It is the same thing that to convolve with a Dirac.
+ if (sigma > 0.006)
+ gaussian_(work_img, coef);
+ /* Convert the result image to the user-requested datatype.
+ FIXME: We are making an unnecessary copy in case the
+ user expects a ntg::float_s image. */
+ level::paste(work_img, out);
+ }
+
+ } // end of namespace mln::linear::impl
+
+ // Facade.
+
+ template <class I, class O>
+ void
+ gaussian(const Image<I>& input, float sigma,
+ Image<O>& output)
+ {
+ recursivefilter_coef_
+ coef(1.68f, 3.735f,
+ 1.783f, 1.723f,
+ -0.6803f, -0.2598f,
+ 0.6318f, 1.997f,
+ sigma);
+
+ gaussian_common_(in, coef, sigma, out);
+ }
+
+# endif // ! MLN_INCLUDE_ONLY
+
+ } // end of namespace mln::linear
+
+} // end of namespace mln
+
+
+
+#endif // MLN_LINEAR_FAST_GAUSSIAN_HH__
Index: trunk/milena/sandbox/nivault/fast_gaussian.hh (deleted)
===================================================================