Add the "stat" attribute.

	*  apps/attributes/CMakeLists.txt,
	*  apps/attributes/stat.cpp: New.

apps/attributes/CMakeLists.txt

-link_libraries(-lfreeimage)
+link_libraries(${FreeImage_LIBRARIES})
 
 add_executable(MSER-patternspec-cli MSER-patternspec-cli.cpp)
 add_executable(meaningfullness-patternspec-cli meaningfullness-patternspec-cli.cpp curvature.cpp)
-add_executable(meaningfullness-cli meaningfullness-cli.cpp curvature.cpp)
\ No newline at end of file
+add_executable(meaningfullness-cli meaningfullness-cli.cpp curvature.cpp)
+add_executable(stat stat.cpp)

apps/attributes/stat.cpp

+#include <mln/core/image/image2d.hpp>
+#include <mln/core/colors.hpp>
+#include <apps/tos/Kinterpolate.hpp>
+#include <mln/morpho/component_tree/io.hpp>
+#include <mln/morpho/component_tree/accumulate.hpp>
+
+#include <mln/accu/accumulators/accu_as_it.hpp>
+#include <mln/accu/accumulators/variance.hpp>
+
+int main(int argc, char** argv)
+{
+  if (argc != 4)
+    {
+      std::cerr << "Usage:" << argv[0] << " tree input.tiff out.csv\n";
+      std::exit(1);
+    }
+
+  using namespace mln;
+
+  const char* tree_path = argv[1];
+  const char* img_path = argv[2];
+  const char* output_path = argv[3];
+
+
+  typedef morpho::component_tree<unsigned, image2d<unsigned> > tree_t;
+  tree_t tree;
+  morpho::load(tree_path, tree);
+
+  image2d<float> ima;
+  io::imread(img_path, ima, true);
+  ima = Kadjust_to(ima, tree._get_data()->m_pmap.domain());
+
+  auto attr = accu::accumulators::accu_as_it< accu::accumulators::variance<float> >();
+  auto res = morpho::vaccumulate(tree, ima, attr);
+  auto res2 = morpho::vaccumulate_proper(tree, ima, attr);
+
+  {
+    std::ofstream f(output_path);
+    f << "Area (S),Average (S),Variance(S),Area (N),Average (N),Variance (N)\n";
+    mln_foreach(auto x, tree.nodes())
+      f << accu::extractor::count(res[x]) << ","
+        << accu::extractor::mean(res[x]) << ","
+        << accu::extractor::variance(res[x]) << ","
+        << accu::extractor::count(res2[x]) << ","
+        << accu::extractor::mean(res2[x]) << ","
+        << accu::extractor::variance(res2[x])
+        << "\n";
+  }
+}