summaryrefslogtreecommitdiff
path: root/thirdparty/linux/include/opencv2/flann.hpp
blob: 19a98f19e5037b884b9ef1378067ddea7bdff80a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
/*M///////////////////////////////////////////////////////////////////////////////////////
//
//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
//  By downloading, copying, installing or using the software you agree to this license.
//  If you do not agree to this license, do not download, install,
//  copy or use the software.
//
//
//                           License Agreement
//                For Open Source Computer Vision Library
//
// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
// Third party copyrights are property of their respective owners.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
//   * Redistribution's of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//
//   * Redistribution's 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.
//
//   * The name of the copyright holders may not be used to endorse or promote products
//     derived from this software without specific prior written permission.
//
// This software is provided by the copyright holders and contributors "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 Intel Corporation or contributors 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.
//
//M*/

#ifndef OPENCV_FLANN_HPP
#define OPENCV_FLANN_HPP

#include "opencv2/core.hpp"
#include "opencv2/flann/miniflann.hpp"
#include "opencv2/flann/flann_base.hpp"

/**
@defgroup flann Clustering and Search in Multi-Dimensional Spaces

This section documents OpenCV's interface to the FLANN library. FLANN (Fast Library for Approximate
Nearest Neighbors) is a library that contains a collection of algorithms optimized for fast nearest
neighbor search in large datasets and for high dimensional features. More information about FLANN
can be found in @cite Muja2009 .
*/

namespace cvflann
{
    CV_EXPORTS flann_distance_t flann_distance_type();
    FLANN_DEPRECATED CV_EXPORTS void set_distance_type(flann_distance_t distance_type, int order);
}


namespace cv
{
namespace flann
{


//! @addtogroup flann
//! @{

template <typename T> struct CvType {};
template <> struct CvType<unsigned char> { static int type() { return CV_8U; } };
template <> struct CvType<char> { static int type() { return CV_8S; } };
template <> struct CvType<unsigned short> { static int type() { return CV_16U; } };
template <> struct CvType<short> { static int type() { return CV_16S; } };
template <> struct CvType<int> { static int type() { return CV_32S; } };
template <> struct CvType<float> { static int type() { return CV_32F; } };
template <> struct CvType<double> { static int type() { return CV_64F; } };


// bring the flann parameters into this namespace
using ::cvflann::get_param;
using ::cvflann::print_params;

// bring the flann distances into this namespace
using ::cvflann::L2_Simple;
using ::cvflann::L2;
using ::cvflann::L1;
using ::cvflann::MinkowskiDistance;
using ::cvflann::MaxDistance;
using ::cvflann::HammingLUT;
using ::cvflann::Hamming;
using ::cvflann::Hamming2;
using ::cvflann::HistIntersectionDistance;
using ::cvflann::HellingerDistance;
using ::cvflann::ChiSquareDistance;
using ::cvflann::KL_Divergence;


/** @brief The FLANN nearest neighbor index class. This class is templated with the type of elements for which
the index is built.
 */
template <typename Distance>
class GenericIndex
{
public:
        typedef typename Distance::ElementType ElementType;
        typedef typename Distance::ResultType DistanceType;

        /** @brief Constructs a nearest neighbor search index for a given dataset.

        @param features Matrix of containing the features(points) to index. The size of the matrix is
        num_features x feature_dimensionality and the data type of the elements in the matrix must
        coincide with the type of the index.
        @param params Structure containing the index parameters. The type of index that will be
        constructed depends on the type of this parameter. See the description.
        @param distance

        The method constructs a fast search structure from a set of features using the specified algorithm
        with specified parameters, as defined by params. params is a reference to one of the following class
        IndexParams descendants:

        - **LinearIndexParams** When passing an object of this type, the index will perform a linear,
        brute-force search. :
        @code
        struct LinearIndexParams : public IndexParams
        {
        };
        @endcode
        - **KDTreeIndexParams** When passing an object of this type the index constructed will consist of
        a set of randomized kd-trees which will be searched in parallel. :
        @code
        struct KDTreeIndexParams : public IndexParams
        {
            KDTreeIndexParams( int trees = 4 );
        };
        @endcode
        - **KMeansIndexParams** When passing an object of this type the index constructed will be a
        hierarchical k-means tree. :
        @code
        struct KMeansIndexParams : public IndexParams
        {
            KMeansIndexParams(
                int branching = 32,
                int iterations = 11,
                flann_centers_init_t centers_init = CENTERS_RANDOM,
                float cb_index = 0.2 );
        };
        @endcode
        - **CompositeIndexParams** When using a parameters object of this type the index created
        combines the randomized kd-trees and the hierarchical k-means tree. :
        @code
        struct CompositeIndexParams : public IndexParams
        {
            CompositeIndexParams(
                int trees = 4,
                int branching = 32,
                int iterations = 11,
                flann_centers_init_t centers_init = CENTERS_RANDOM,
                float cb_index = 0.2 );
        };
        @endcode
        - **LshIndexParams** When using a parameters object of this type the index created uses
        multi-probe LSH (by Multi-Probe LSH: Efficient Indexing for High-Dimensional Similarity Search
        by Qin Lv, William Josephson, Zhe Wang, Moses Charikar, Kai Li., Proceedings of the 33rd
        International Conference on Very Large Data Bases (VLDB). Vienna, Austria. September 2007) :
        @code
        struct LshIndexParams : public IndexParams
        {
            LshIndexParams(
                unsigned int table_number,
                unsigned int key_size,
                unsigned int multi_probe_level );
        };
        @endcode
        - **AutotunedIndexParams** When passing an object of this type the index created is
        automatically tuned to offer the best performance, by choosing the optimal index type
        (randomized kd-trees, hierarchical kmeans, linear) and parameters for the dataset provided. :
        @code
        struct AutotunedIndexParams : public IndexParams
        {
            AutotunedIndexParams(
                float target_precision = 0.9,
                float build_weight = 0.01,
                float memory_weight = 0,
                float sample_fraction = 0.1 );
        };
        @endcode
        - **SavedIndexParams** This object type is used for loading a previously saved index from the
        disk. :
        @code
        struct SavedIndexParams : public IndexParams
        {
            SavedIndexParams( String filename );
        };
        @endcode
         */
        GenericIndex(const Mat& features, const ::cvflann::IndexParams& params, Distance distance = Distance());

        ~GenericIndex();

        /** @brief Performs a K-nearest neighbor search for a given query point using the index.

        @param query The query point
        @param indices Vector that will contain the indices of the K-nearest neighbors found. It must have
        at least knn size.
        @param dists Vector that will contain the distances to the K-nearest neighbors found. It must have
        at least knn size.
        @param knn Number of nearest neighbors to search for.
        @param params SearchParams
         */
        void knnSearch(const std::vector<ElementType>& query, std::vector<int>& indices,
                       std::vector<DistanceType>& dists, int knn, const ::cvflann::SearchParams& params);
        void knnSearch(const Mat& queries, Mat& indices, Mat& dists, int knn, const ::cvflann::SearchParams& params);

        int radiusSearch(const std::vector<ElementType>& query, std::vector<int>& indices,
                         std::vector<DistanceType>& dists, DistanceType radius, const ::cvflann::SearchParams& params);
        int radiusSearch(const Mat& query, Mat& indices, Mat& dists,
                         DistanceType radius, const ::cvflann::SearchParams& params);

        void save(String filename) { nnIndex->save(filename); }

        int veclen() const { return nnIndex->veclen(); }

        int size() const { return nnIndex->size(); }

        ::cvflann::IndexParams getParameters() { return nnIndex->getParameters(); }

        FLANN_DEPRECATED const ::cvflann::IndexParams* getIndexParameters() { return nnIndex->getIndexParameters(); }

private:
        ::cvflann::Index<Distance>* nnIndex;
};

//! @cond IGNORED

#define FLANN_DISTANCE_CHECK \
    if ( ::cvflann::flann_distance_type() != cvflann::FLANN_DIST_L2) { \
        printf("[WARNING] You are using cv::flann::Index (or cv::flann::GenericIndex) and have also changed "\
        "the distance using cvflann::set_distance_type. This is no longer working as expected "\
        "(cv::flann::Index always uses L2). You should create the index templated on the distance, "\
        "for example for L1 distance use: GenericIndex< L1<float> > \n"); \
    }


template <typename Distance>
GenericIndex<Distance>::GenericIndex(const Mat& dataset, const ::cvflann::IndexParams& params, Distance distance)
{
    CV_Assert(dataset.type() == CvType<ElementType>::type());
    CV_Assert(dataset.isContinuous());
    ::cvflann::Matrix<ElementType> m_dataset((ElementType*)dataset.ptr<ElementType>(0), dataset.rows, dataset.cols);

    nnIndex = new ::cvflann::Index<Distance>(m_dataset, params, distance);

    FLANN_DISTANCE_CHECK

    nnIndex->buildIndex();
}

template <typename Distance>
GenericIndex<Distance>::~GenericIndex()
{
    delete nnIndex;
}

template <typename Distance>
void GenericIndex<Distance>::knnSearch(const std::vector<ElementType>& query, std::vector<int>& indices, std::vector<DistanceType>& dists, int knn, const ::cvflann::SearchParams& searchParams)
{
    ::cvflann::Matrix<ElementType> m_query((ElementType*)&query[0], 1, query.size());
    ::cvflann::Matrix<int> m_indices(&indices[0], 1, indices.size());
    ::cvflann::Matrix<DistanceType> m_dists(&dists[0], 1, dists.size());

    FLANN_DISTANCE_CHECK

    nnIndex->knnSearch(m_query,m_indices,m_dists,knn,searchParams);
}


template <typename Distance>
void GenericIndex<Distance>::knnSearch(const Mat& queries, Mat& indices, Mat& dists, int knn, const ::cvflann::SearchParams& searchParams)
{
    CV_Assert(queries.type() == CvType<ElementType>::type());
    CV_Assert(queries.isContinuous());
    ::cvflann::Matrix<ElementType> m_queries((ElementType*)queries.ptr<ElementType>(0), queries.rows, queries.cols);

    CV_Assert(indices.type() == CV_32S);
    CV_Assert(indices.isContinuous());
    ::cvflann::Matrix<int> m_indices((int*)indices.ptr<int>(0), indices.rows, indices.cols);

    CV_Assert(dists.type() == CvType<DistanceType>::type());
    CV_Assert(dists.isContinuous());
    ::cvflann::Matrix<DistanceType> m_dists((DistanceType*)dists.ptr<DistanceType>(0), dists.rows, dists.cols);

    FLANN_DISTANCE_CHECK

    nnIndex->knnSearch(m_queries,m_indices,m_dists,knn, searchParams);
}

template <typename Distance>
int GenericIndex<Distance>::radiusSearch(const std::vector<ElementType>& query, std::vector<int>& indices, std::vector<DistanceType>& dists, DistanceType radius, const ::cvflann::SearchParams& searchParams)
{
    ::cvflann::Matrix<ElementType> m_query((ElementType*)&query[0], 1, query.size());
    ::cvflann::Matrix<int> m_indices(&indices[0], 1, indices.size());
    ::cvflann::Matrix<DistanceType> m_dists(&dists[0], 1, dists.size());

    FLANN_DISTANCE_CHECK

    return nnIndex->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
}

template <typename Distance>
int GenericIndex<Distance>::radiusSearch(const Mat& query, Mat& indices, Mat& dists, DistanceType radius, const ::cvflann::SearchParams& searchParams)
{
    CV_Assert(query.type() == CvType<ElementType>::type());
    CV_Assert(query.isContinuous());
    ::cvflann::Matrix<ElementType> m_query((ElementType*)query.ptr<ElementType>(0), query.rows, query.cols);

    CV_Assert(indices.type() == CV_32S);
    CV_Assert(indices.isContinuous());
    ::cvflann::Matrix<int> m_indices((int*)indices.ptr<int>(0), indices.rows, indices.cols);

    CV_Assert(dists.type() == CvType<DistanceType>::type());
    CV_Assert(dists.isContinuous());
    ::cvflann::Matrix<DistanceType> m_dists((DistanceType*)dists.ptr<DistanceType>(0), dists.rows, dists.cols);

    FLANN_DISTANCE_CHECK

    return nnIndex->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
}

//! @endcond

/**
 * @deprecated Use GenericIndex class instead
 */
template <typename T>
class Index_
{
public:
    typedef typename L2<T>::ElementType ElementType;
    typedef typename L2<T>::ResultType DistanceType;

    FLANN_DEPRECATED Index_(const Mat& dataset, const ::cvflann::IndexParams& params)
    {
        printf("[WARNING] The cv::flann::Index_<T> class is deperecated, use cv::flann::GenericIndex<Distance> instead\n");

        CV_Assert(dataset.type() == CvType<ElementType>::type());
        CV_Assert(dataset.isContinuous());
        ::cvflann::Matrix<ElementType> m_dataset((ElementType*)dataset.ptr<ElementType>(0), dataset.rows, dataset.cols);

        if ( ::cvflann::flann_distance_type() == cvflann::FLANN_DIST_L2 ) {
            nnIndex_L1 = NULL;
            nnIndex_L2 = new ::cvflann::Index< L2<ElementType> >(m_dataset, params);
        }
        else if ( ::cvflann::flann_distance_type() == cvflann::FLANN_DIST_L1 ) {
            nnIndex_L1 = new ::cvflann::Index< L1<ElementType> >(m_dataset, params);
            nnIndex_L2 = NULL;
        }
        else {
            printf("[ERROR] cv::flann::Index_<T> only provides backwards compatibility for the L1 and L2 distances. "
                   "For other distance types you must use cv::flann::GenericIndex<Distance>\n");
            CV_Assert(0);
        }
        if (nnIndex_L1) nnIndex_L1->buildIndex();
        if (nnIndex_L2) nnIndex_L2->buildIndex();
    }
    FLANN_DEPRECATED ~Index_()
    {
        if (nnIndex_L1) delete nnIndex_L1;
        if (nnIndex_L2) delete nnIndex_L2;
    }

    FLANN_DEPRECATED void knnSearch(const std::vector<ElementType>& query, std::vector<int>& indices, std::vector<DistanceType>& dists, int knn, const ::cvflann::SearchParams& searchParams)
    {
        ::cvflann::Matrix<ElementType> m_query((ElementType*)&query[0], 1, query.size());
        ::cvflann::Matrix<int> m_indices(&indices[0], 1, indices.size());
        ::cvflann::Matrix<DistanceType> m_dists(&dists[0], 1, dists.size());

        if (nnIndex_L1) nnIndex_L1->knnSearch(m_query,m_indices,m_dists,knn,searchParams);
        if (nnIndex_L2) nnIndex_L2->knnSearch(m_query,m_indices,m_dists,knn,searchParams);
    }
    FLANN_DEPRECATED void knnSearch(const Mat& queries, Mat& indices, Mat& dists, int knn, const ::cvflann::SearchParams& searchParams)
    {
        CV_Assert(queries.type() == CvType<ElementType>::type());
        CV_Assert(queries.isContinuous());
        ::cvflann::Matrix<ElementType> m_queries((ElementType*)queries.ptr<ElementType>(0), queries.rows, queries.cols);

        CV_Assert(indices.type() == CV_32S);
        CV_Assert(indices.isContinuous());
        ::cvflann::Matrix<int> m_indices((int*)indices.ptr<int>(0), indices.rows, indices.cols);

        CV_Assert(dists.type() == CvType<DistanceType>::type());
        CV_Assert(dists.isContinuous());
        ::cvflann::Matrix<DistanceType> m_dists((DistanceType*)dists.ptr<DistanceType>(0), dists.rows, dists.cols);

        if (nnIndex_L1) nnIndex_L1->knnSearch(m_queries,m_indices,m_dists,knn, searchParams);
        if (nnIndex_L2) nnIndex_L2->knnSearch(m_queries,m_indices,m_dists,knn, searchParams);
    }

    FLANN_DEPRECATED int radiusSearch(const std::vector<ElementType>& query, std::vector<int>& indices, std::vector<DistanceType>& dists, DistanceType radius, const ::cvflann::SearchParams& searchParams)
    {
        ::cvflann::Matrix<ElementType> m_query((ElementType*)&query[0], 1, query.size());
        ::cvflann::Matrix<int> m_indices(&indices[0], 1, indices.size());
        ::cvflann::Matrix<DistanceType> m_dists(&dists[0], 1, dists.size());

        if (nnIndex_L1) return nnIndex_L1->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
        if (nnIndex_L2) return nnIndex_L2->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
    }

    FLANN_DEPRECATED int radiusSearch(const Mat& query, Mat& indices, Mat& dists, DistanceType radius, const ::cvflann::SearchParams& searchParams)
    {
        CV_Assert(query.type() == CvType<ElementType>::type());
        CV_Assert(query.isContinuous());
        ::cvflann::Matrix<ElementType> m_query((ElementType*)query.ptr<ElementType>(0), query.rows, query.cols);

        CV_Assert(indices.type() == CV_32S);
        CV_Assert(indices.isContinuous());
        ::cvflann::Matrix<int> m_indices((int*)indices.ptr<int>(0), indices.rows, indices.cols);

        CV_Assert(dists.type() == CvType<DistanceType>::type());
        CV_Assert(dists.isContinuous());
        ::cvflann::Matrix<DistanceType> m_dists((DistanceType*)dists.ptr<DistanceType>(0), dists.rows, dists.cols);

        if (nnIndex_L1) return nnIndex_L1->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
        if (nnIndex_L2) return nnIndex_L2->radiusSearch(m_query,m_indices,m_dists,radius,searchParams);
    }

    FLANN_DEPRECATED void save(String filename)
    {
        if (nnIndex_L1) nnIndex_L1->save(filename);
        if (nnIndex_L2) nnIndex_L2->save(filename);
    }

    FLANN_DEPRECATED int veclen() const
    {
        if (nnIndex_L1) return nnIndex_L1->veclen();
        if (nnIndex_L2) return nnIndex_L2->veclen();
    }

    FLANN_DEPRECATED int size() const
    {
        if (nnIndex_L1) return nnIndex_L1->size();
        if (nnIndex_L2) return nnIndex_L2->size();
    }

    FLANN_DEPRECATED ::cvflann::IndexParams getParameters()
    {
        if (nnIndex_L1) return nnIndex_L1->getParameters();
        if (nnIndex_L2) return nnIndex_L2->getParameters();

    }

    FLANN_DEPRECATED const ::cvflann::IndexParams* getIndexParameters()
    {
        if (nnIndex_L1) return nnIndex_L1->getIndexParameters();
        if (nnIndex_L2) return nnIndex_L2->getIndexParameters();
    }

private:
    // providing backwards compatibility for L2 and L1 distances (most common)
    ::cvflann::Index< L2<ElementType> >* nnIndex_L2;
    ::cvflann::Index< L1<ElementType> >* nnIndex_L1;
};


/** @brief Clusters features using hierarchical k-means algorithm.

@param features The points to be clustered. The matrix must have elements of type
Distance::ElementType.
@param centers The centers of the clusters obtained. The matrix must have type
Distance::ResultType. The number of rows in this matrix represents the number of clusters desired,
however, because of the way the cut in the hierarchical tree is chosen, the number of clusters
computed will be the highest number of the form (branching-1)\*k+1 that's lower than the number of
clusters desired, where branching is the tree's branching factor (see description of the
KMeansIndexParams).
@param params Parameters used in the construction of the hierarchical k-means tree.
@param d Distance to be used for clustering.

The method clusters the given feature vectors by constructing a hierarchical k-means tree and
choosing a cut in the tree that minimizes the cluster's variance. It returns the number of clusters
found.
 */
template <typename Distance>
int hierarchicalClustering(const Mat& features, Mat& centers, const ::cvflann::KMeansIndexParams& params,
                           Distance d = Distance())
{
    typedef typename Distance::ElementType ElementType;
    typedef typename Distance::ResultType DistanceType;

    CV_Assert(features.type() == CvType<ElementType>::type());
    CV_Assert(features.isContinuous());
    ::cvflann::Matrix<ElementType> m_features((ElementType*)features.ptr<ElementType>(0), features.rows, features.cols);

    CV_Assert(centers.type() == CvType<DistanceType>::type());
    CV_Assert(centers.isContinuous());
    ::cvflann::Matrix<DistanceType> m_centers((DistanceType*)centers.ptr<DistanceType>(0), centers.rows, centers.cols);

    return ::cvflann::hierarchicalClustering<Distance>(m_features, m_centers, params, d);
}

/** @deprecated
*/
template <typename ELEM_TYPE, typename DIST_TYPE>
FLANN_DEPRECATED int hierarchicalClustering(const Mat& features, Mat& centers, const ::cvflann::KMeansIndexParams& params)
{
    printf("[WARNING] cv::flann::hierarchicalClustering<ELEM_TYPE,DIST_TYPE> is deprecated, use "
        "cv::flann::hierarchicalClustering<Distance> instead\n");

    if ( ::cvflann::flann_distance_type() == cvflann::FLANN_DIST_L2 ) {
        return hierarchicalClustering< L2<ELEM_TYPE> >(features, centers, params);
    }
    else if ( ::cvflann::flann_distance_type() == cvflann::FLANN_DIST_L1 ) {
        return hierarchicalClustering< L1<ELEM_TYPE> >(features, centers, params);
    }
    else {
        printf("[ERROR] cv::flann::hierarchicalClustering<ELEM_TYPE,DIST_TYPE> only provides backwards "
        "compatibility for the L1 and L2 distances. "
        "For other distance types you must use cv::flann::hierarchicalClustering<Distance>\n");
        CV_Assert(0);
    }
}

//! @} flann

} } // namespace cv::flann

#endif