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diff --git a/ml/dlib/dlib/statistics/image_feature_sampling.h b/ml/dlib/dlib/statistics/image_feature_sampling.h
new file mode 100644
index 000000000..f04f9926e
--- /dev/null
+++ b/ml/dlib/dlib/statistics/image_feature_sampling.h
@@ -0,0 +1,82 @@
+// Copyright (C) 2011  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+#ifndef DLIB_IMAGE_FEATURE_SaMPLING_Hh_
+#define DLIB_IMAGE_FEATURE_SaMPLING_Hh_
+
+#include "image_feature_sampling_abstract.h"
+#include "../statistics.h"
+
+namespace dlib
+{
+
+// ----------------------------------------------------------------------------------------
+
+    template <
+        typename image_array_type,
+        typename feature_extractor_type,
+        typename pyramid_type
+        >
+    random_subset_selector<typename feature_extractor_type::descriptor_type> randomly_sample_image_features (
+        const image_array_type& images,
+        const pyramid_type& pyr,
+        const feature_extractor_type& fe_,
+        unsigned long num
+    )
+    {
+        feature_extractor_type fe;
+        fe.copy_configuration(fe_);
+        random_subset_selector<typename feature_extractor_type::descriptor_type> basis;
+        basis.set_max_size(num);
+
+        typedef typename image_array_type::type image_type;
+        image_type temp_img, temp_img2;
+
+        for (unsigned long i = 0; i < images.size(); ++i)
+        {
+            bool at_pyramid_top = true;
+            while (true)
+            {
+                if (at_pyramid_top)
+                    fe.load(images[i]);
+                else
+                    fe.load(temp_img);
+                
+                if (fe.size() == 0)
+                    break;
+
+                for (long r = 0; r < fe.nr(); ++r)
+                {
+                    for (long c = 0; c < fe.nc(); ++c)
+                    {
+                        if (basis.next_add_accepts())
+                        {
+                            basis.add(fe(r,c));
+                        }
+                        else
+                        {
+                            basis.add();
+                        }
+                    }
+                }
+
+                if (at_pyramid_top)
+                {
+                    at_pyramid_top = false;
+                    pyr(images[i], temp_img);
+                }
+                else
+                {
+                    pyr(temp_img, temp_img2);
+                    swap(temp_img2,temp_img);
+                }
+            }
+        }
+        return basis;
+    }
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_IMAGE_FEATURE_SaMPLING_Hh_
+