22 Jun
2012
22 Jun
'12
6:40 p.m.
---
scribo/sauvola_fast.cc | 175 ++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 175 insertions(+), 0 deletions(-)
create mode 100644 scribo/sauvola_fast.cc
diff --git a/scribo/sauvola_fast.cc b/scribo/sauvola_fast.cc
new file mode 100644
index 0000000..8018135
--- /dev/null
+++ b/scribo/sauvola_fast.cc
@@ -0,0 +1,175 @@
+#include <mln/core/image/image2d.hh>
+#include <scribo/canvas/integral_browsing.hh>
+#include <mln/io/pgm/load.hh>
+#include <mln/io/pbm/save.hh>
+#include <mln/util/couple.hh>
+#include <mln/util/timer.hh>
+#include <scribo/binarization/internal/sauvola_formula.hh>
+
+namespace mln
+{
+
+ template <typename I>
+ struct sauvola_fast_functor
+ {
+
+ const I& input;
+ typedef mln_ch_value(I,bool) bin_t;
+ bin_t bin;
+
+ mln_fwd_pixter(const I) pi;
+ mln_fwd_pixter(bin_t) po;
+
+ double K_;
+ double R_;
+
+ scribo::binarization::internal::sauvola_formula formula_;
+
+ unsigned count_;
+
+ sauvola_fast_functor(const I& input_, mln_ch_value(I,bool)& bin_, double K,
double R)
+ : input(input_),
+ bin(bin_),
+ pi(input),
+ po(bin),
+ K_(K),
+ R_(R)
+ {
+ pi.start();
+ po.start();
+ count_ = 0;
+ }
+
+ void exec(double mean, double stddev)
+ {
+ static point2d p(0,0);
+ po.val() = (pi.val() <= formula_(p, mean, stddev, K_, R_));
+
+ pi.next(); // next pixel
+ po.next(); // next pixel
+
+ ++count_;
+ }
+
+ void finalize()
+ {
+ std::cout << input.domain().nsites() << " - " <<
input.domain().nrows() * input.domain().ncols() << " - " << count_
<< std::endl;
+ }
+
+ };
+
+
+
+
+ template <typename I, typename J>
+ void
+ init_integral(const Image<I>& input_,
+ Image<J>& integral_sum_sum_2_)
+ {
+ trace::entering("subsampling::impl::integral_3");
+
+ const I& input = exact(input_);
+ J& integral_sum_sum_2 = exact(integral_sum_sum_2_);
+
+ mln_precondition(input.is_valid());
+ mln_precondition(input.domain().pmin() == literal::origin);
+
+ typedef mln_value(I) V;
+ typedef mln_sum(V) S;
+ typedef mln_value(J) V2;
+ typedef mln_site(I) P;
+
+ initialize(integral_sum_sum_2, input);
+ V2* p_integ = integral_sum_sum_2.buffer();
+
+ const int up = input.delta_index(dpoint2d(-1, 0));
+
+ const unsigned nrows = input.domain().nrows();
+ const unsigned ncols = input.domain().ncols();
+
+ unsigned row = 0;
+
+ unsigned b_offset = input.delta_index(dpoint2d(input.border(),
+ input.border()));
+ p_integ += b_offset;
+ {
+ S h_sum = 0, h_sum_2 = 0;
+ const V* ptr1 = & input.at_(row, 0);
+ for (unsigned col = 0; col < ncols; ++col)
+ {
+ V v = *ptr1++;
+
+ h_sum += v;
+ h_sum_2 += v * v;
+
+ // exception
+ p_integ->first() = h_sum;
+ p_integ->second() = h_sum_2;
+
+ ++p_integ;
+ }
+ }
+
+ unsigned b_next = 2 * input.border();
+
+ p_integ += b_next;
+
+ for (row += 1; row < nrows; ++row)
+ {
+ S h_sum = 0, h_sum_2 = 0;
+ const V* ptr1 = & input.at_(row, 0);
+ for (unsigned col = 0; col < ncols; ++col)
+ {
+ V v = *ptr1++;
+
+ h_sum += v;
+ h_sum_2 += v * v;
+
+ p_integ->first() = h_sum + (p_integ + up)->first();
+ p_integ->second() = h_sum_2 + (p_integ + up)->second();
+
+ ++p_integ;
+ }
+
+ p_integ += b_next;
+ }
+
+ trace::exiting("subsampling::impl::integral_3");
+ }
+
+
+
+ image2d<bool>
+ sauvola_fast(const image2d<value::int_u8>& input, unsigned win)
+ {
+ image2d<util::couple<double,double> > integral;
+ init_integral(input, integral);
+
+ image2d<bool> output;
+ initialize(output, input);
+ sauvola_fast_functor<image2d<value::int_u8> > f(input, output,
SCRIBO_DEFAULT_SAUVOLA_K, SCRIBO_DEFAULT_SAUVOLA_R);
+ scribo::canvas::integral_browsing(integral, 1, win, win, 1, f);
+
+ return f.bin;
+ }
+
+}
+
+
+int main(int argc, char *argv[])
+{
+ using namespace mln;
+
+ image2d<value::int_u8> input;
+ io::pgm::load(input, argv[1]);
+
+ unsigned win = atoi(argv[2]);
+
+ util::timer t;
+ t.start();
+ image2d<bool> output = sauvola_fast(input, win);
+ t.stop();
+ std::cout << t << std::endl;
+
+ io::pbm::save(output, argv[3]);
+}
--
1.7.2.5