Diff: include/opencv2/flann/ground_truth.h

Revision:

0:0e0631af0305

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/opencv2/flann/ground_truth.h	Fri Jan 29 04:53:38 2021 +0000
@@ -0,0 +1,94 @@
+/***********************************************************************
+ * Software License Agreement (BSD License)
+ *
+ * Copyright 2008-2009  Marius Muja (mariusm@cs.ubc.ca). All rights reserved.
+ * Copyright 2008-2009  David G. Lowe (lowe@cs.ubc.ca). All rights reserved.
+ *
+ * THE BSD LICENSE
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *************************************************************************/
+
+#ifndef OPENCV_FLANN_GROUND_TRUTH_H_
+#define OPENCV_FLANN_GROUND_TRUTH_H_
+
+#include "dist.h"
+#include "matrix.h"
+
+
+namespace cvflann
+{
+
+template <typename Distance>
+void find_nearest(const Matrix<typename Distance::ElementType>& dataset, typename Distance::ElementType* query, int* matches, int nn,
+                  int skip = 0, Distance distance = Distance())
+{
+    typedef typename Distance::ResultType DistanceType;
+    int n = nn + skip;
+
+    std::vector<int> match(n);
+    std::vector<DistanceType> dists(n);
+
+    dists[0] = distance(dataset[0], query, dataset.cols);
+    match[0] = 0;
+    int dcnt = 1;
+
+    for (size_t i=1; i<dataset.rows; ++i) {
+        DistanceType tmp = distance(dataset[i], query, dataset.cols);
+
+        if (dcnt<n) {
+            match[dcnt] = (int)i;
+            dists[dcnt++] = tmp;
+        }
+        else if (tmp < dists[dcnt-1]) {
+            dists[dcnt-1] = tmp;
+            match[dcnt-1] = (int)i;
+        }
+
+        int j = dcnt-1;
+        // bubble up
+        while (j>=1 && dists[j]<dists[j-1]) {
+            std::swap(dists[j],dists[j-1]);
+            std::swap(match[j],match[j-1]);
+            j--;
+        }
+    }
+
+    for (int i=0; i<nn; ++i) {
+        matches[i] = match[i+skip];
+    }
+}
+
+
+template <typename Distance>
+void compute_ground_truth(const Matrix<typename Distance::ElementType>& dataset, const Matrix<typename Distance::ElementType>& testset, Matrix<int>& matches,
+                          int skip=0, Distance d = Distance())
+{
+    for (size_t i=0; i<testset.rows; ++i) {
+        find_nearest<Distance>(dataset, testset[i], matches[i], (int)matches.cols, skip, d);
+    }
+}
+
+
+}
+
+#endif //OPENCV_FLANN_GROUND_TRUTH_H_