Diff: include/opencv2/flann/nn_index.h

Revision:

0:0e0631af0305

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/opencv2/flann/nn_index.h	Fri Jan 29 04:53:38 2021 +0000
@@ -0,0 +1,177 @@
+/***********************************************************************
+ * 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_NNINDEX_H
+#define OPENCV_FLANN_NNINDEX_H
+
+#include "general.h"
+#include "matrix.h"
+#include "result_set.h"
+#include "params.h"
+
+namespace cvflann
+{
+
+/**
+ * Nearest-neighbour index base class
+ */
+template <typename Distance>
+class NNIndex
+{
+    typedef typename Distance::ElementType ElementType;
+    typedef typename Distance::ResultType DistanceType;
+
+public:
+
+    virtual ~NNIndex() {}
+
+    /**
+     * \brief Builds the index
+     */
+    virtual void buildIndex() = 0;
+
+    /**
+     * \brief Perform k-nearest neighbor search
+     * \param[in] queries The query points for which to find the nearest neighbors
+     * \param[out] indices The indices of the nearest neighbors found
+     * \param[out] dists Distances to the nearest neighbors found
+     * \param[in] knn Number of nearest neighbors to return
+     * \param[in] params Search parameters
+     */
+    virtual void knnSearch(const Matrix<ElementType>& queries, Matrix<int>& indices, Matrix<DistanceType>& dists, int knn, const SearchParams& params)
+    {
+        assert(queries.cols == veclen());
+        assert(indices.rows >= queries.rows);
+        assert(dists.rows >= queries.rows);
+        assert(int(indices.cols) >= knn);
+        assert(int(dists.cols) >= knn);
+
+#if 0
+        KNNResultSet<DistanceType> resultSet(knn);
+        for (size_t i = 0; i < queries.rows; i++) {
+            resultSet.init(indices[i], dists[i]);
+            findNeighbors(resultSet, queries[i], params);
+        }
+#else
+        KNNUniqueResultSet<DistanceType> resultSet(knn);
+        for (size_t i = 0; i < queries.rows; i++) {
+            resultSet.clear();
+            findNeighbors(resultSet, queries[i], params);
+            if (get_param(params,"sorted",true)) resultSet.sortAndCopy(indices[i], dists[i], knn);
+            else resultSet.copy(indices[i], dists[i], knn);
+        }
+#endif
+    }
+
+    /**
+     * \brief Perform radius search
+     * \param[in] query The query point
+     * \param[out] indices The indinces of the neighbors found within the given radius
+     * \param[out] dists The distances to the nearest neighbors found
+     * \param[in] radius The radius used for search
+     * \param[in] params Search parameters
+     * \returns Number of neighbors found
+     */
+    virtual int radiusSearch(const Matrix<ElementType>& query, Matrix<int>& indices, Matrix<DistanceType>& dists, float radius, const SearchParams& params)
+    {
+        if (query.rows != 1) {
+            fprintf(stderr, "I can only search one feature at a time for range search\n");
+            return -1;
+        }
+        assert(query.cols == veclen());
+        assert(indices.cols == dists.cols);
+
+        int n = 0;
+        int* indices_ptr = NULL;
+        DistanceType* dists_ptr = NULL;
+        if (indices.cols > 0) {
+            n = (int)indices.cols;
+            indices_ptr = indices[0];
+            dists_ptr = dists[0];
+        }
+
+        RadiusUniqueResultSet<DistanceType> resultSet((DistanceType)radius);
+        resultSet.clear();
+        findNeighbors(resultSet, query[0], params);
+        if (n>0) {
+            if (get_param(params,"sorted",true)) resultSet.sortAndCopy(indices_ptr, dists_ptr, n);
+            else resultSet.copy(indices_ptr, dists_ptr, n);
+        }
+
+        return (int)resultSet.size();
+    }
+
+    /**
+     * \brief Saves the index to a stream
+     * \param stream The stream to save the index to
+     */
+    virtual void saveIndex(FILE* stream) = 0;
+
+    /**
+     * \brief Loads the index from a stream
+     * \param stream The stream from which the index is loaded
+     */
+    virtual void loadIndex(FILE* stream) = 0;
+
+    /**
+     * \returns number of features in this index.
+     */
+    virtual size_t size() const = 0;
+
+    /**
+     * \returns The dimensionality of the features in this index.
+     */
+    virtual size_t veclen() const = 0;
+
+    /**
+     * \returns The amount of memory (in bytes) used by the index.
+     */
+    virtual int usedMemory() const = 0;
+
+    /**
+     * \returns The index type (kdtree, kmeans,...)
+     */
+    virtual flann_algorithm_t getType() const = 0;
+
+    /**
+     * \returns The index parameters
+     */
+    virtual IndexParams getParameters() const = 0;
+
+
+    /**
+     * \brief Method that searches for nearest-neighbours
+     */
+    virtual void findNeighbors(ResultSet<DistanceType>& result, const ElementType* vec, const SearchParams& searchParams) = 0;
+};
+
+}
+
+#endif //OPENCV_FLANN_NNINDEX_H