Set a default value for the second argument of test_box_overlap's constructor.

Also added overlaps_any_box().

dlib/image_processing/box_overlap_testing.h

@@ -19,9 +19,9 @@ namespace dlib
         ) : match_thresh(0.5), overlap_thresh(1.0)
         {}
 
-        test_box_overlap (
+        explicit test_box_overlap (
             double match_thresh_,
-            double overlap_thresh_
+            double overlap_thresh_ = 1.0
         ) : match_thresh(match_thresh_), overlap_thresh(overlap_thresh_) 
         {
             // make sure requires clause is not broken
@@ -127,6 +127,22 @@ namespace dlib
         return test_box_overlap(max_match_score, max_overlap);
     }
 
+// ----------------------------------------------------------------------------------------
+
+    inline bool overlaps_any_box (
+        const test_box_overlap& tester,
+        const std::vector<rectangle>& rects,
+        const rectangle& rect
+    )
+    {
+        for (unsigned long i = 0; i < rects.size(); ++i)
+        {
+            if (tester(rects[i],rect))
+                return true;
+        }
+        return false;
+    }
+
 // ----------------------------------------------------------------------------------------
 
 }

dlib/image_processing/box_overlap_testing_abstract.h

@@ -32,9 +32,9 @@ namespace dlib
                 - #get_overlap_thresh() == 1.0
         !*/
 
-        test_box_overlap (
+        explicit test_box_overlap (
             double match_thresh,
-            double overlap_thresh
+            double overlap_thresh = 1.0
         );
         /*!
             requires
@@ -117,6 +117,19 @@ namespace dlib
                         - TBO(A,B) == false
     !*/
 
+// ----------------------------------------------------------------------------------------
+
+    bool overlaps_any_box (
+        const test_box_overlap& tester,
+        const std::vector<rectangle>& rects,
+        const rectangle& rect
+    );
+    /*!
+        ensures
+            - returns true if rect overlaps any box in rects and false otherwise.  Overlap
+              is determined based on the given tester object.
+    !*/
+
 // ----------------------------------------------------------------------------------------
 
 }