root/modules/features2d/src/matchers.cpp

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DEFINITIONS

This source file includes following definitions.
  1. ensureSizeIsEnough
  2. ocl_matchSingle
  3. ocl_matchConvert
  4. ocl_matchDownload
  5. ocl_knnMatchSingle
  6. ocl_knnMatchConvert
  7. ocl_knnMatchDownload
  8. ocl_radiusMatchSingle
  9. ocl_radiusMatchConvert
  10. ocl_radiusMatchDownload
  11. set
  12. clear
  13. getDescriptor
  14. getDescriptors
  15. getDescriptor
  16. getLocalIdx
  17. size
  18. convertMatches
  19. add
  20. getTrainDescriptors
  21. clear
  22. empty
  23. train
  24. match
  25. knnMatch
  26. radiusMatch
  27. match
  28. checkMasks
  29. knnMatch
  30. radiusMatch
  31. read
  32. write
  33. isPossibleMatch
  34. isMaskedOut
  35. clone
  36. ocl_match
  37. ocl_knnMatch
  38. knnMatchImpl
  39. ocl_radiusMatch
  40. radiusMatchImpl
  41. create
  42. addedDescCount
  43. add
  44. clear
  45. train
  46. read
  47. write
  48. isMaskSupported
  49. clone
  50. convertToDMatches
  51. knnMatchImpl
  52. radiusMatchImpl

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#include "precomp.hpp"
#include <limits>
#include "opencl_kernels_features2d.hpp"

#if defined(HAVE_EIGEN) && EIGEN_WORLD_VERSION == 2
#include <Eigen/Array>
#endif

namespace cv
{

/////////////////////// ocl functions for BFMatcher ///////////////////////////

static void ensureSizeIsEnough(int rows, int cols, int type, UMat &m)
{
    if (m.type() == type && m.rows >= rows && m.cols >= cols)
        m = m(Rect(0, 0, cols, rows));
    else
        m.create(rows, cols, type);
}

static bool ocl_matchSingle(InputArray query, InputArray train,
        UMat &trainIdx, UMat &distance, int distType)
{
    if (query.empty() || train.empty())
        return false;

    const int query_rows = query.rows();
    const int query_cols = query.cols();

    ensureSizeIsEnough(1, query_rows, CV_32S, trainIdx);
    ensureSizeIsEnough(1, query_rows, CV_32F, distance);

    ocl::Device devDef = ocl::Device::getDefault();

    UMat uquery = query.getUMat(), utrain = train.getUMat();
    int kercn = 1;
    if (devDef.isIntel() &&
        (0 == (uquery.step % 4)) && (0 == (uquery.cols % 4)) && (0 == (uquery.offset % 4)) &&
        (0 == (utrain.step % 4)) && (0 == (utrain.cols % 4)) && (0 == (utrain.offset % 4)))
        kercn = 4;

    int block_size = 16;
    int max_desc_len = 0;
    bool is_cpu = devDef.type() == ocl::Device::TYPE_CPU;
    if (query_cols <= 64)
        max_desc_len = 64 / kercn;
    else if (query_cols <= 128 && !is_cpu)
        max_desc_len = 128 / kercn;

    int depth = query.depth();
    cv::String opts;
    opts = cv::format("-D T=%s -D TN=%s -D kercn=%d %s -D DIST_TYPE=%d -D BLOCK_SIZE=%d -D MAX_DESC_LEN=%d",
        ocl::typeToStr(depth), ocl::typeToStr(CV_MAKETYPE(depth, kercn)), kercn, depth == CV_32F ? "-D T_FLOAT" : "", distType, block_size, max_desc_len);
    ocl::Kernel k("BruteForceMatch_Match", ocl::features2d::brute_force_match_oclsrc, opts);
    if(k.empty())
        return false;

    size_t globalSize[] = {(query.size().height + block_size - 1) / block_size * block_size, block_size};
    size_t localSize[] = {block_size, block_size};

    int idx = 0;
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(uquery));
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(utrain));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(trainIdx));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(distance));
    idx = k.set(idx, uquery.rows);
    idx = k.set(idx, uquery.cols);
    idx = k.set(idx, utrain.rows);
    idx = k.set(idx, utrain.cols);
    idx = k.set(idx, (int)(uquery.step / sizeof(float)));

    return k.run(2, globalSize, localSize, false);
}

static bool ocl_matchConvert(const Mat &trainIdx, const Mat &distance, std::vector< std::vector<DMatch> > &matches)
{
    if (trainIdx.empty() || distance.empty())
        return false;

    if( (trainIdx.type() != CV_32SC1) || (distance.type() != CV_32FC1 || distance.cols != trainIdx.cols) )
        return false;

    const int nQuery = trainIdx.cols;

    matches.clear();
    matches.reserve(nQuery);

    const int *trainIdx_ptr = trainIdx.ptr<int>();
    const float *distance_ptr =  distance.ptr<float>();
    for (int queryIdx = 0; queryIdx < nQuery; ++queryIdx, ++trainIdx_ptr, ++distance_ptr)
    {
        int trainIndex = *trainIdx_ptr;

        if (trainIndex == -1)
            continue;

        float dst = *distance_ptr;

        DMatch m(queryIdx, trainIndex, 0, dst);

        std::vector<DMatch> temp;
        temp.push_back(m);
        matches.push_back(temp);
    }
    return true;
}

static bool ocl_matchDownload(const UMat &trainIdx, const UMat &distance, std::vector< std::vector<DMatch> > &matches)
{
    if (trainIdx.empty() || distance.empty())
        return false;

    Mat trainIdxCPU = trainIdx.getMat(ACCESS_READ);
    Mat distanceCPU = distance.getMat(ACCESS_READ);

    return ocl_matchConvert(trainIdxCPU, distanceCPU, matches);
}

static bool ocl_knnMatchSingle(InputArray query, InputArray train, UMat &trainIdx,
                               UMat &distance, int distType)
{
    if (query.empty() || train.empty())
        return false;

    const int query_rows = query.rows();
    const int query_cols = query.cols();

    ensureSizeIsEnough(1, query_rows, CV_32SC2, trainIdx);
    ensureSizeIsEnough(1, query_rows, CV_32FC2, distance);

    trainIdx.setTo(Scalar::all(-1));

    ocl::Device devDef = ocl::Device::getDefault();

    UMat uquery = query.getUMat(), utrain = train.getUMat();
    int kercn = 1;
    if (devDef.isIntel() &&
        (0 == (uquery.step % 4)) && (0 == (uquery.cols % 4)) && (0 == (uquery.offset % 4)) &&
        (0 == (utrain.step % 4)) && (0 == (utrain.cols % 4)) && (0 == (utrain.offset % 4)))
        kercn = 4;

    int block_size = 16;
    int max_desc_len = 0;
    bool is_cpu = devDef.type() == ocl::Device::TYPE_CPU;
    if (query_cols <= 64)
        max_desc_len = 64 / kercn;
    else if (query_cols <= 128 && !is_cpu)
        max_desc_len = 128 / kercn;

    int depth = query.depth();
    cv::String opts;
    opts = cv::format("-D T=%s -D TN=%s -D kercn=%d %s -D DIST_TYPE=%d -D BLOCK_SIZE=%d -D MAX_DESC_LEN=%d",
        ocl::typeToStr(depth), ocl::typeToStr(CV_MAKETYPE(depth, kercn)), kercn, depth == CV_32F ? "-D T_FLOAT" : "", distType, block_size, max_desc_len);
    ocl::Kernel k("BruteForceMatch_knnMatch", ocl::features2d::brute_force_match_oclsrc, opts);
    if(k.empty())
        return false;

    size_t globalSize[] = {(query_rows + block_size - 1) / block_size * block_size, block_size};
    size_t localSize[] = {block_size, block_size};

    int idx = 0;
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(uquery));
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(utrain));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(trainIdx));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(distance));
    idx = k.set(idx, uquery.rows);
    idx = k.set(idx, uquery.cols);
    idx = k.set(idx, utrain.rows);
    idx = k.set(idx, utrain.cols);
    idx = k.set(idx, (int)(uquery.step / sizeof(float)));

    return k.run(2, globalSize, localSize, false);
}

static bool ocl_knnMatchConvert(const Mat &trainIdx, const Mat &distance, std::vector< std::vector<DMatch> > &matches, bool compactResult)
{
    if (trainIdx.empty() || distance.empty())
        return false;

    if(trainIdx.type() != CV_32SC2 && trainIdx.type() != CV_32SC1) return false;
    if(distance.type() != CV_32FC2 && distance.type() != CV_32FC1)return false;
    if(distance.size() != trainIdx.size()) return false;
    if(!trainIdx.isContinuous() || !distance.isContinuous()) return false;

    const int nQuery = trainIdx.type() == CV_32SC2 ? trainIdx.cols : trainIdx.rows;
    const int k = trainIdx.type() == CV_32SC2 ? 2 : trainIdx.cols;

    matches.clear();
    matches.reserve(nQuery);

    const int *trainIdx_ptr = trainIdx.ptr<int>();
    const float *distance_ptr = distance.ptr<float>();

    for (int queryIdx = 0; queryIdx < nQuery; ++queryIdx)
    {
        matches.push_back(std::vector<DMatch>());
        std::vector<DMatch> &curMatches = matches.back();
        curMatches.reserve(k);

        for (int i = 0; i < k; ++i, ++trainIdx_ptr, ++distance_ptr)
        {
            int trainIndex = *trainIdx_ptr;

            if (trainIndex != -1)
            {
                float dst = *distance_ptr;

                DMatch m(queryIdx, trainIndex, 0, dst);

                curMatches.push_back(m);
            }
        }

        if (compactResult && curMatches.empty())
            matches.pop_back();
    }
    return true;
}

static bool ocl_knnMatchDownload(const UMat &trainIdx, const UMat &distance, std::vector< std::vector<DMatch> > &matches, bool compactResult)
{
    if (trainIdx.empty() || distance.empty())
        return false;

    Mat trainIdxCPU = trainIdx.getMat(ACCESS_READ);
    Mat distanceCPU = distance.getMat(ACCESS_READ);

    return ocl_knnMatchConvert(trainIdxCPU, distanceCPU, matches, compactResult);
}

static bool ocl_radiusMatchSingle(InputArray query, InputArray train,
        UMat &trainIdx,   UMat &distance, UMat &nMatches, float maxDistance, int distType)
{
    if (query.empty() || train.empty())
        return false;

    const int query_rows = query.rows();
    const int train_rows = train.rows();

    ensureSizeIsEnough(1, query_rows, CV_32SC1, nMatches);

    if (trainIdx.empty())
    {
        ensureSizeIsEnough(query_rows, std::max((train_rows / 100), 10), CV_32SC1, trainIdx);
        ensureSizeIsEnough(query_rows, std::max((train_rows / 100), 10), CV_32FC1, distance);
    }

    nMatches.setTo(Scalar::all(0));

    ocl::Device devDef = ocl::Device::getDefault();
    UMat uquery = query.getUMat(), utrain = train.getUMat();
    int kercn = 1;
    if (devDef.isIntel() &&
        (0 == (uquery.step % 4)) && (0 == (uquery.cols % 4)) && (0 == (uquery.offset % 4)) &&
        (0 == (utrain.step % 4)) && (0 == (utrain.cols % 4)) && (0 == (utrain.offset % 4)))
        kercn = 4;

    int block_size = 16;
    int depth = query.depth();
    cv::String opts;
    opts = cv::format("-D T=%s -D TN=%s -D kercn=%d %s -D DIST_TYPE=%d -D BLOCK_SIZE=%d",
        ocl::typeToStr(depth), ocl::typeToStr(CV_MAKETYPE(depth, kercn)), kercn, depth == CV_32F ? "-D T_FLOAT" : "", distType, block_size);
    ocl::Kernel k("BruteForceMatch_RadiusMatch", ocl::features2d::brute_force_match_oclsrc, opts);
    if (k.empty())
        return false;

    size_t globalSize[] = {(train_rows + block_size - 1) / block_size * block_size, (query_rows + block_size - 1) / block_size * block_size};
    size_t localSize[] = {block_size, block_size};

    int idx = 0;
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(uquery));
    idx = k.set(idx, ocl::KernelArg::PtrReadOnly(utrain));
    idx = k.set(idx, maxDistance);
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(trainIdx));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(distance));
    idx = k.set(idx, ocl::KernelArg::PtrWriteOnly(nMatches));
    idx = k.set(idx, uquery.rows);
    idx = k.set(idx, uquery.cols);
    idx = k.set(idx, utrain.rows);
    idx = k.set(idx, utrain.cols);
    idx = k.set(idx, trainIdx.cols);
    idx = k.set(idx, (int)(uquery.step / sizeof(float)));
    idx = k.set(idx, (int)(trainIdx.step / sizeof(int)));

    return k.run(2, globalSize, localSize, false);
}

static bool ocl_radiusMatchConvert(const Mat &trainIdx, const Mat &distance, const Mat &_nMatches,
        std::vector< std::vector<DMatch> > &matches, bool compactResult)
{
    if (trainIdx.empty() || distance.empty() || _nMatches.empty())
        return false;

    if( (trainIdx.type() != CV_32SC1) ||
        (distance.type() != CV_32FC1 || distance.size() != trainIdx.size()) ||
        (_nMatches.type() != CV_32SC1 || _nMatches.cols != trainIdx.rows) )
        return false;

    const int nQuery = trainIdx.rows;

    matches.clear();
    matches.reserve(nQuery);

    const int *nMatches_ptr = _nMatches.ptr<int>();

    for (int queryIdx = 0; queryIdx < nQuery; ++queryIdx)
    {
        const int *trainIdx_ptr = trainIdx.ptr<int>(queryIdx);
        const float *distance_ptr = distance.ptr<float>(queryIdx);

        const int nMatches = std::min(nMatches_ptr[queryIdx], trainIdx.cols);

        if (nMatches == 0)
        {
            if (!compactResult)
                matches.push_back(std::vector<DMatch>());
            continue;
        }

        matches.push_back(std::vector<DMatch>(nMatches));
        std::vector<DMatch> &curMatches = matches.back();

        for (int i = 0; i < nMatches; ++i, ++trainIdx_ptr, ++distance_ptr)
        {
            int trainIndex = *trainIdx_ptr;

            float dst = *distance_ptr;

            DMatch m(queryIdx, trainIndex, 0, dst);

            curMatches[i] = m;
        }

        std::sort(curMatches.begin(), curMatches.end());
    }
    return true;
}

static bool ocl_radiusMatchDownload(const UMat &trainIdx, const UMat &distance, const UMat &nMatches,
        std::vector< std::vector<DMatch> > &matches, bool compactResult)
{
    if (trainIdx.empty() || distance.empty() || nMatches.empty())
        return false;

    Mat trainIdxCPU = trainIdx.getMat(ACCESS_READ);
    Mat distanceCPU = distance.getMat(ACCESS_READ);
    Mat nMatchesCPU = nMatches.getMat(ACCESS_READ);

    return ocl_radiusMatchConvert(trainIdxCPU, distanceCPU, nMatchesCPU, matches, compactResult);
}

/****************************************************************************************\
*                                      DescriptorMatcher                                 *
\****************************************************************************************/
DescriptorMatcher::DescriptorCollection::DescriptorCollection()
{}

DescriptorMatcher::DescriptorCollection::DescriptorCollection( const DescriptorCollection& collection )
{
    mergedDescriptors = collection.mergedDescriptors.clone();
    std::copy( collection.startIdxs.begin(), collection.startIdxs.begin(), startIdxs.begin() );
}

DescriptorMatcher::DescriptorCollection::~DescriptorCollection()
{}

void DescriptorMatcher::DescriptorCollection::set( const std::vector<Mat>& descriptors )
{
    clear();

    size_t imageCount = descriptors.size();
    CV_Assert( imageCount > 0 );

    startIdxs.resize( imageCount );

    int dim = -1;
    int type = -1;
    startIdxs[0] = 0;
    for( size_t i = 1; i < imageCount; i++ )
    {
        int s = 0;
        if( !descriptors[i-1].empty() )
        {
            dim = descriptors[i-1].cols;
            type = descriptors[i-1].type();
            s = descriptors[i-1].rows;
        }
        startIdxs[i] = startIdxs[i-1] + s;
    }
    if( imageCount == 1 )
    {
        if( descriptors[0].empty() ) return;

        dim = descriptors[0].cols;
        type = descriptors[0].type();
    }
    CV_Assert( dim > 0 );

    int count = startIdxs[imageCount-1] + descriptors[imageCount-1].rows;

    if( count > 0 )
    {
        mergedDescriptors.create( count, dim, type );
        for( size_t i = 0; i < imageCount; i++ )
        {
            if( !descriptors[i].empty() )
            {
                CV_Assert( descriptors[i].cols == dim && descriptors[i].type() == type );
                Mat m = mergedDescriptors.rowRange( startIdxs[i], startIdxs[i] + descriptors[i].rows );
                descriptors[i].copyTo(m);
            }
        }
    }
}

void DescriptorMatcher::DescriptorCollection::clear()
{
    startIdxs.clear();
    mergedDescriptors.release();
}

const Mat DescriptorMatcher::DescriptorCollection::getDescriptor( int imgIdx, int localDescIdx ) const
{
    CV_Assert( imgIdx < (int)startIdxs.size() );
    int globalIdx = startIdxs[imgIdx] + localDescIdx;
    CV_Assert( globalIdx < (int)size() );

    return getDescriptor( globalIdx );
}

const Mat& DescriptorMatcher::DescriptorCollection::getDescriptors() const
{
    return mergedDescriptors;
}

const Mat DescriptorMatcher::DescriptorCollection::getDescriptor( int globalDescIdx ) const
{
    CV_Assert( globalDescIdx < size() );
    return mergedDescriptors.row( globalDescIdx );
}

void DescriptorMatcher::DescriptorCollection::getLocalIdx( int globalDescIdx, int& imgIdx, int& localDescIdx ) const
{
    CV_Assert( (globalDescIdx>=0) && (globalDescIdx < size()) );
    std::vector<int>::const_iterator img_it = std::upper_bound(startIdxs.begin(), startIdxs.end(), globalDescIdx);
    --img_it;
    imgIdx = (int)(img_it - startIdxs.begin());
    localDescIdx = globalDescIdx - (*img_it);
}

int DescriptorMatcher::DescriptorCollection::size() const
{
    return mergedDescriptors.rows;
}

/*
 * DescriptorMatcher
 */
static void convertMatches( const std::vector<std::vector<DMatch> >& knnMatches, std::vector<DMatch>& matches )
{
    matches.clear();
    matches.reserve( knnMatches.size() );
    for( size_t i = 0; i < knnMatches.size(); i++ )
    {
        CV_Assert( knnMatches[i].size() <= 1 );
        if( !knnMatches[i].empty() )
            matches.push_back( knnMatches[i][0] );
    }
}

DescriptorMatcher::~DescriptorMatcher()
{}

void DescriptorMatcher::add( InputArrayOfArrays _descriptors )
{
    if(_descriptors.isUMatVector())
    {
        std::vector<UMat> descriptors;
        _descriptors.getUMatVector(descriptors);
        utrainDescCollection.insert( utrainDescCollection.end(), descriptors.begin(), descriptors.end() );
    }
    else if(_descriptors.isUMat())
    {
        std::vector<UMat> descriptors = std::vector<UMat>(1, _descriptors.getUMat());
        utrainDescCollection.insert( utrainDescCollection.end(), descriptors.begin(), descriptors.end() );
    }
    else if(_descriptors.isMatVector())
    {
        std::vector<Mat> descriptors;
        _descriptors.getMatVector(descriptors);
        trainDescCollection.insert( trainDescCollection.end(), descriptors.begin(), descriptors.end() );
    }
    else if(_descriptors.isMat())
    {
        std::vector<Mat> descriptors = std::vector<Mat>(1, _descriptors.getMat());
        trainDescCollection.insert( trainDescCollection.end(), descriptors.begin(), descriptors.end() );
    }
    else
        CV_Assert( _descriptors.isUMat() || _descriptors.isUMatVector() || _descriptors.isMat() || _descriptors.isMatVector() );
}

const std::vector<Mat>& DescriptorMatcher::getTrainDescriptors() const
{
    return trainDescCollection;
}

void DescriptorMatcher::clear()
{
    utrainDescCollection.clear();
    trainDescCollection.clear();
}

bool DescriptorMatcher::empty() const
{
    return trainDescCollection.empty() && utrainDescCollection.empty();
}

void DescriptorMatcher::train()
{}

void DescriptorMatcher::match( InputArray queryDescriptors, InputArray trainDescriptors,
                              std::vector<DMatch>& matches, InputArray mask ) const
{
    Ptr<DescriptorMatcher> tempMatcher = clone(true);
    tempMatcher->add(trainDescriptors);
    tempMatcher->match( queryDescriptors, matches, std::vector<Mat>(1, mask.getMat()) );
}

void DescriptorMatcher::knnMatch( InputArray queryDescriptors, InputArray trainDescriptors,
                                  std::vector<std::vector<DMatch> >& matches, int knn,
                                  InputArray mask, bool compactResult ) const
{
    Ptr<DescriptorMatcher> tempMatcher = clone(true);
    tempMatcher->add(trainDescriptors);
    tempMatcher->knnMatch( queryDescriptors, matches, knn, std::vector<Mat>(1, mask.getMat()), compactResult );
}

void DescriptorMatcher::radiusMatch( InputArray queryDescriptors, InputArray trainDescriptors,
                                     std::vector<std::vector<DMatch> >& matches, float maxDistance, InputArray mask,
                                     bool compactResult ) const
{
    Ptr<DescriptorMatcher> tempMatcher = clone(true);
    tempMatcher->add(trainDescriptors);
    tempMatcher->radiusMatch( queryDescriptors, matches, maxDistance, std::vector<Mat>(1, mask.getMat()), compactResult );
}

void DescriptorMatcher::match( InputArray queryDescriptors, std::vector<DMatch>& matches, InputArrayOfArrays masks )
{
    std::vector<std::vector<DMatch> > knnMatches;
    knnMatch( queryDescriptors, knnMatches, 1, masks, true /*compactResult*/ );
    convertMatches( knnMatches, matches );
}

void DescriptorMatcher::checkMasks( InputArrayOfArrays _masks, int queryDescriptorsCount ) const
{
    std::vector<Mat> masks;
    _masks.getMatVector(masks);

    if( isMaskSupported() && !masks.empty() )
    {
        // Check masks
        size_t imageCount = std::max(trainDescCollection.size(), utrainDescCollection.size() );
        CV_Assert( masks.size() == imageCount );
        for( size_t i = 0; i < imageCount; i++ )
        {
            if( !masks[i].empty() && (!trainDescCollection[i].empty() || !utrainDescCollection[i].empty() ) )
            {
                int rows = trainDescCollection[i].empty() ? utrainDescCollection[i].rows : trainDescCollection[i].rows;
                    CV_Assert( masks[i].rows == queryDescriptorsCount &&
                        (masks[i].cols == rows || masks[i].cols == rows) &&
                        masks[i].type() == CV_8UC1 );
            }
        }
    }
}

void DescriptorMatcher::knnMatch( InputArray queryDescriptors, std::vector<std::vector<DMatch> >& matches, int knn,
                                  InputArrayOfArrays masks, bool compactResult )
{
    if( empty() || queryDescriptors.empty() )
        return;

    CV_Assert( knn > 0 );

    checkMasks( masks, queryDescriptors.size().height );

    train();
    knnMatchImpl( queryDescriptors, matches, knn, masks, compactResult );
}

void DescriptorMatcher::radiusMatch( InputArray queryDescriptors, std::vector<std::vector<DMatch> >& matches, float maxDistance,
                                     InputArrayOfArrays masks, bool compactResult )
{
    matches.clear();
    if( empty() || queryDescriptors.empty() )
        return;

    CV_Assert( maxDistance > std::numeric_limits<float>::epsilon() );

    checkMasks( masks, queryDescriptors.size().height );

    train();
    radiusMatchImpl( queryDescriptors, matches, maxDistance, masks, compactResult );
}

void DescriptorMatcher::read( const FileNode& )
{}

void DescriptorMatcher::write( FileStorage& ) const
{}

bool DescriptorMatcher::isPossibleMatch( InputArray _mask, int queryIdx, int trainIdx )
{
    Mat mask = _mask.getMat();
    return mask.empty() || mask.at<uchar>(queryIdx, trainIdx);
}

bool DescriptorMatcher::isMaskedOut( InputArrayOfArrays _masks, int queryIdx )
{
    std::vector<Mat> masks;
    _masks.getMatVector(masks);

    size_t outCount = 0;
    for( size_t i = 0; i < masks.size(); i++ )
    {
        if( !masks[i].empty() && (countNonZero(masks[i].row(queryIdx)) == 0) )
            outCount++;
    }

    return !masks.empty() && outCount == masks.size() ;
}


////////////////////////////////////////////////////// BruteForceMatcher /////////////////////////////////////////////////

BFMatcher::BFMatcher( int _normType, bool _crossCheck )
{
    normType = _normType;
    crossCheck = _crossCheck;
}

Ptr<DescriptorMatcher> BFMatcher::clone( bool emptyTrainData ) const
{
    Ptr<BFMatcher> matcher = makePtr<BFMatcher>(normType, crossCheck);
    if( !emptyTrainData )
    {
        matcher->trainDescCollection.resize(trainDescCollection.size());
        std::transform( trainDescCollection.begin(), trainDescCollection.end(),
                        matcher->trainDescCollection.begin(), clone_op );
    }
    return matcher;
}

static bool ocl_match(InputArray query, InputArray _train, std::vector< std::vector<DMatch> > &matches, int dstType)
{
    UMat trainIdx, distance;
    if (!ocl_matchSingle(query, _train, trainIdx, distance, dstType))
        return false;
    if (!ocl_matchDownload(trainIdx, distance, matches))
        return false;
    return true;
}

static bool ocl_knnMatch(InputArray query, InputArray _train, std::vector< std::vector<DMatch> > &matches, int k, int dstType, bool compactResult)
{
    UMat trainIdx, distance;
    if (k != 2)
        return false;
    if (!ocl_knnMatchSingle(query, _train, trainIdx, distance, dstType))
        return false;
    if (!ocl_knnMatchDownload(trainIdx, distance, matches, compactResult) )
        return false;
    return true;
}

void BFMatcher::knnMatchImpl( InputArray _queryDescriptors, std::vector<std::vector<DMatch> >& matches, int knn,
                             InputArrayOfArrays _masks, bool compactResult )
{
    int trainDescType = trainDescCollection.empty() ? utrainDescCollection[0].type() : trainDescCollection[0].type();
    CV_Assert( _queryDescriptors.type() == trainDescType );

    const int IMGIDX_SHIFT = 18;
    const int IMGIDX_ONE = (1 << IMGIDX_SHIFT);

    if( _queryDescriptors.empty() || (trainDescCollection.empty() && utrainDescCollection.empty()))
    {
        matches.clear();
        return;
    }

    std::vector<Mat> masks;
    _masks.getMatVector(masks);

    if(!trainDescCollection.empty() && !utrainDescCollection.empty())
    {
        for(int i = 0; i < (int)utrainDescCollection.size(); i++)
        {
            Mat tempMat;
            utrainDescCollection[i].copyTo(tempMat);
            trainDescCollection.push_back(tempMat);
        }
        utrainDescCollection.clear();
    }

    int trainDescVectorSize = trainDescCollection.empty() ? (int)utrainDescCollection.size() : (int)trainDescCollection.size();
    Size trainDescSize = trainDescCollection.empty() ? utrainDescCollection[0].size() : trainDescCollection[0].size();
    int trainDescOffset = trainDescCollection.empty() ? (int)utrainDescCollection[0].offset : 0;

    if ( ocl::useOpenCL() && _queryDescriptors.isUMat() && _queryDescriptors.dims()<=2 && trainDescVectorSize == 1 &&
        _queryDescriptors.type() == CV_32FC1 && _queryDescriptors.offset() == 0 && trainDescOffset == 0 &&
        trainDescSize.width == _queryDescriptors.size().width && masks.size() == 1 && masks[0].total() == 0 )
    {
        if(knn == 1)
        {
            if(trainDescCollection.empty())
            {
                if(ocl_match(_queryDescriptors, utrainDescCollection[0], matches, normType))
                {
                    CV_IMPL_ADD(CV_IMPL_OCL);
                    return;
                }
            }
            else
            {
                if(ocl_match(_queryDescriptors, trainDescCollection[0], matches, normType))
                {
                    CV_IMPL_ADD(CV_IMPL_OCL);
                    return;
                }
            }
        }
        else
        {
            if(trainDescCollection.empty())
            {
                if(ocl_knnMatch(_queryDescriptors, utrainDescCollection[0], matches, knn, normType, compactResult) )
                {
                    CV_IMPL_ADD(CV_IMPL_OCL);
                    return;
                }
            }
            else
            {
                if(ocl_knnMatch(_queryDescriptors, trainDescCollection[0], matches, knn, normType, compactResult) )
                {
                    CV_IMPL_ADD(CV_IMPL_OCL);
                    return;
                }
            }
        }
    }

    Mat queryDescriptors = _queryDescriptors.getMat();
    if(trainDescCollection.empty() && !utrainDescCollection.empty())
    {
        for(int i = 0; i < (int)utrainDescCollection.size(); i++)
        {
            Mat tempMat;
            utrainDescCollection[i].copyTo(tempMat);
            trainDescCollection.push_back(tempMat);
        }
        utrainDescCollection.clear();
    }

    matches.reserve(queryDescriptors.rows);

    Mat dist, nidx;

    int iIdx, imgCount = (int)trainDescCollection.size(), update = 0;
    int dtype = normType == NORM_HAMMING || normType == NORM_HAMMING2 ||
        (normType == NORM_L1 && queryDescriptors.type() == CV_8U) ? CV_32S : CV_32F;

    CV_Assert( (int64)imgCount*IMGIDX_ONE < INT_MAX );

    for( iIdx = 0; iIdx < imgCount; iIdx++ )
    {
        CV_Assert( trainDescCollection[iIdx].rows < IMGIDX_ONE );
        batchDistance(queryDescriptors, trainDescCollection[iIdx], dist, dtype, nidx,
                      normType, knn, masks.empty() ? Mat() : masks[iIdx], update, crossCheck);
        update += IMGIDX_ONE;
    }

    if( dtype == CV_32S )
    {
        Mat temp;
        dist.convertTo(temp, CV_32F);
        dist = temp;
    }

    for( int qIdx = 0; qIdx < queryDescriptors.rows; qIdx++ )
    {
        const float* distptr = dist.ptr<float>(qIdx);
        const int* nidxptr = nidx.ptr<int>(qIdx);

        matches.push_back( std::vector<DMatch>() );
        std::vector<DMatch>& mq = matches.back();
        mq.reserve(knn);

        for( int k = 0; k < nidx.cols; k++ )
        {
            if( nidxptr[k] < 0 )
                break;
            mq.push_back( DMatch(qIdx, nidxptr[k] & (IMGIDX_ONE - 1),
                          nidxptr[k] >> IMGIDX_SHIFT, distptr[k]) );
        }

        if( mq.empty() && compactResult )
            matches.pop_back();
    }
}

static bool ocl_radiusMatch(InputArray query, InputArray _train, std::vector< std::vector<DMatch> > &matches,
        float maxDistance, int dstType, bool compactResult)
{
    UMat trainIdx, distance, nMatches;
    if (!ocl_radiusMatchSingle(query, _train, trainIdx, distance, nMatches, maxDistance, dstType))
        return false;
    if (!ocl_radiusMatchDownload(trainIdx, distance, nMatches, matches, compactResult))
        return false;
    return true;
}

void BFMatcher::radiusMatchImpl( InputArray _queryDescriptors, std::vector<std::vector<DMatch> >& matches,
                                float maxDistance, InputArrayOfArrays _masks, bool compactResult )
{
    int trainDescType = trainDescCollection.empty() ? utrainDescCollection[0].type() : trainDescCollection[0].type();
    CV_Assert( _queryDescriptors.type() == trainDescType );

    if( _queryDescriptors.empty() || (trainDescCollection.empty() && utrainDescCollection.empty()))
    {
        matches.clear();
        return;
    }

    std::vector<Mat> masks;
    _masks.getMatVector(masks);

    if(!trainDescCollection.empty() && !utrainDescCollection.empty())
    {
        for(int i = 0; i < (int)utrainDescCollection.size(); i++)
        {
            Mat tempMat;
            utrainDescCollection[i].copyTo(tempMat);
            trainDescCollection.push_back(tempMat);
        }
        utrainDescCollection.clear();
    }

    int trainDescVectorSize = trainDescCollection.empty() ? (int)utrainDescCollection.size() : (int)trainDescCollection.size();
    Size trainDescSize = trainDescCollection.empty() ? utrainDescCollection[0].size() : trainDescCollection[0].size();
    int trainDescOffset = trainDescCollection.empty() ? (int)utrainDescCollection[0].offset : 0;

    if ( ocl::useOpenCL() && _queryDescriptors.isUMat() && _queryDescriptors.dims()<=2 && trainDescVectorSize == 1 &&
        _queryDescriptors.type() == CV_32FC1 && _queryDescriptors.offset() == 0 && trainDescOffset == 0 &&
        trainDescSize.width == _queryDescriptors.size().width && masks.size() == 1 && masks[0].total() == 0 )
    {
        if (trainDescCollection.empty())
        {
            if(ocl_radiusMatch(_queryDescriptors, utrainDescCollection[0], matches, maxDistance, normType, compactResult) )
            {
                CV_IMPL_ADD(CV_IMPL_OCL);
                return;
            }
        }
        else
        {
            if (ocl_radiusMatch(_queryDescriptors, trainDescCollection[0], matches, maxDistance, normType, compactResult) )
            {
                CV_IMPL_ADD(CV_IMPL_OCL);
                return;
            }
        }
    }

    Mat queryDescriptors = _queryDescriptors.getMat();
    if(trainDescCollection.empty() && !utrainDescCollection.empty())
    {
        for(int i = 0; i < (int)utrainDescCollection.size(); i++)
        {
            Mat tempMat;
            utrainDescCollection[i].copyTo(tempMat);
            trainDescCollection.push_back(tempMat);
        }
        utrainDescCollection.clear();
    }

    matches.resize(queryDescriptors.rows);
    Mat dist, distf;

    int iIdx, imgCount = (int)trainDescCollection.size();
    int dtype = normType == NORM_HAMMING ||
        (normType == NORM_L1 && queryDescriptors.type() == CV_8U) ? CV_32S : CV_32F;

    for( iIdx = 0; iIdx < imgCount; iIdx++ )
    {
        batchDistance(queryDescriptors, trainDescCollection[iIdx], dist, dtype, noArray(),
                      normType, 0, masks.empty() ? Mat() : masks[iIdx], 0, false);
        if( dtype == CV_32S )
            dist.convertTo(distf, CV_32F);
        else
            distf = dist;

        for( int qIdx = 0; qIdx < queryDescriptors.rows; qIdx++ )
        {
            const float* distptr = distf.ptr<float>(qIdx);

            std::vector<DMatch>& mq = matches[qIdx];
            for( int k = 0; k < distf.cols; k++ )
            {
                if( distptr[k] <= maxDistance )
                    mq.push_back( DMatch(qIdx, k, iIdx, distptr[k]) );
            }
        }
    }

    int qIdx0 = 0;
    for( int qIdx = 0; qIdx < queryDescriptors.rows; qIdx++ )
    {
        if( matches[qIdx].empty() && compactResult )
            continue;

        if( qIdx0 < qIdx )
            std::swap(matches[qIdx], matches[qIdx0]);

        std::sort( matches[qIdx0].begin(), matches[qIdx0].end() );
        qIdx0++;
    }
}

///////////////////////////////////////////////////////////////////////////////////////////////////////

/*
 * Factory function for DescriptorMatcher creating
 */
Ptr<DescriptorMatcher> DescriptorMatcher::create( const String& descriptorMatcherType )
{
    Ptr<DescriptorMatcher> dm;
    if( !descriptorMatcherType.compare( "FlannBased" ) )
    {
        dm = makePtr<FlannBasedMatcher>();
    }
    else if( !descriptorMatcherType.compare( "BruteForce" ) ) // L2
    {
        dm = makePtr<BFMatcher>(int(NORM_L2)); // anonymous enums can't be template parameters
    }
    else if( !descriptorMatcherType.compare( "BruteForce-SL2" ) ) // Squared L2
    {
        dm = makePtr<BFMatcher>(int(NORM_L2SQR));
    }
    else if( !descriptorMatcherType.compare( "BruteForce-L1" ) )
    {
        dm = makePtr<BFMatcher>(int(NORM_L1));
    }
    else if( !descriptorMatcherType.compare("BruteForce-Hamming") ||
             !descriptorMatcherType.compare("BruteForce-HammingLUT") )
    {
        dm = makePtr<BFMatcher>(int(NORM_HAMMING));
    }
    else if( !descriptorMatcherType.compare("BruteForce-Hamming(2)") )
    {
        dm = makePtr<BFMatcher>(int(NORM_HAMMING2));
    }
    else
        CV_Error( Error::StsBadArg, "Unknown matcher name" );

    return dm;
}


/*
 * Flann based matcher
 */
FlannBasedMatcher::FlannBasedMatcher( const Ptr<flann::IndexParams>& _indexParams, const Ptr<flann::SearchParams>& _searchParams )
    : indexParams(_indexParams), searchParams(_searchParams), addedDescCount(0)
{
    CV_Assert( _indexParams );
    CV_Assert( _searchParams );
}

void FlannBasedMatcher::add( InputArrayOfArrays _descriptors )
{
    DescriptorMatcher::add( _descriptors );
    std::vector<UMat> descriptors;
    _descriptors.getUMatVector(descriptors);

    for( size_t i = 0; i < descriptors.size(); i++ )
    {
        addedDescCount += descriptors[i].rows;
    }
}

void FlannBasedMatcher::clear()
{
    DescriptorMatcher::clear();

    mergedDescriptors.clear();
    flannIndex.release();

    addedDescCount = 0;
}

void FlannBasedMatcher::train()
{
    if( !flannIndex || mergedDescriptors.size() < addedDescCount )
    {
        // FIXIT: Workaround for 'utrainDescCollection' issue (PR #2142)
        if (!utrainDescCollection.empty())
        {
            CV_Assert(trainDescCollection.size() == 0);
            for (size_t i = 0; i < utrainDescCollection.size(); ++i)
                trainDescCollection.push_back(utrainDescCollection[i].getMat(ACCESS_READ));
        }
        mergedDescriptors.set( trainDescCollection );
        flannIndex = makePtr<flann::Index>( mergedDescriptors.getDescriptors(), *indexParams );
    }
}

void FlannBasedMatcher::read( const FileNode& fn)
{
     if (!indexParams)
         indexParams = makePtr<flann::IndexParams>();

     FileNode ip = fn["indexParams"];
     CV_Assert(ip.type() == FileNode::SEQ);

     for(int i = 0; i < (int)ip.size(); ++i)
     {
        CV_Assert(ip[i].type() == FileNode::MAP);
        String _name =  (String)ip[i]["name"];
        int type =  (int)ip[i]["type"];

        switch(type)
        {
        case CV_8U:
        case CV_8S:
        case CV_16U:
        case CV_16S:
        case CV_32S:
            indexParams->setInt(_name, (int) ip[i]["value"]);
            break;
        case CV_32F:
            indexParams->setFloat(_name, (float) ip[i]["value"]);
            break;
        case CV_64F:
            indexParams->setDouble(_name, (double) ip[i]["value"]);
            break;
        case CV_USRTYPE1:
            indexParams->setString(_name, (String) ip[i]["value"]);
            break;
        case CV_MAKETYPE(CV_USRTYPE1,2):
            indexParams->setBool(_name, (int) ip[i]["value"] != 0);
            break;
        case CV_MAKETYPE(CV_USRTYPE1,3):
            indexParams->setAlgorithm((int) ip[i]["value"]);
            break;
        };
     }

     if (!searchParams)
         searchParams = makePtr<flann::SearchParams>();

     FileNode sp = fn["searchParams"];
     CV_Assert(sp.type() == FileNode::SEQ);

     for(int i = 0; i < (int)sp.size(); ++i)
     {
        CV_Assert(sp[i].type() == FileNode::MAP);
        String _name =  (String)sp[i]["name"];
        int type =  (int)sp[i]["type"];

        switch(type)
        {
        case CV_8U:
        case CV_8S:
        case CV_16U:
        case CV_16S:
        case CV_32S:
            searchParams->setInt(_name, (int) sp[i]["value"]);
            break;
        case CV_32F:
            searchParams->setFloat(_name, (float) ip[i]["value"]);
            break;
        case CV_64F:
            searchParams->setDouble(_name, (double) ip[i]["value"]);
            break;
        case CV_USRTYPE1:
            searchParams->setString(_name, (String) ip[i]["value"]);
            break;
        case CV_MAKETYPE(CV_USRTYPE1,2):
            searchParams->setBool(_name, (int) ip[i]["value"] != 0);
            break;
        case CV_MAKETYPE(CV_USRTYPE1,3):
            searchParams->setAlgorithm((int) ip[i]["value"]);
            break;
        };
     }

    flannIndex.release();
}

void FlannBasedMatcher::write( FileStorage& fs) const
{
     fs << "indexParams" << "[";

     if (indexParams)
     {
         std::vector<String> names;
         std::vector<int> types;
         std::vector<String> strValues;
         std::vector<double> numValues;

         indexParams->getAll(names, types, strValues, numValues);

         for(size_t i = 0; i < names.size(); ++i)
         {
             fs << "{" << "name" << names[i] << "type" << types[i] << "value";
             switch(types[i])
             {
             case CV_8U:
                 fs << (uchar)numValues[i];
                 break;
             case CV_8S:
                 fs << (char)numValues[i];
                 break;
             case CV_16U:
                 fs << (ushort)numValues[i];
                 break;
             case CV_16S:
                 fs << (short)numValues[i];
                 break;
             case CV_32S:
             case CV_MAKETYPE(CV_USRTYPE1,2):
             case CV_MAKETYPE(CV_USRTYPE1,3):
                 fs << (int)numValues[i];
                 break;
             case CV_32F:
                 fs << (float)numValues[i];
                 break;
             case CV_64F:
                 fs << (double)numValues[i];
                 break;
             case CV_USRTYPE1:
                 fs << strValues[i];
                 break;
             default:
                 fs << (double)numValues[i];
                 fs << "typename" << strValues[i];
                 break;
             }
             fs << "}";
         }
     }

     fs << "]" << "searchParams" << "[";

     if (searchParams)
     {
         std::vector<String> names;
         std::vector<int> types;
         std::vector<String> strValues;
         std::vector<double> numValues;

         searchParams->getAll(names, types, strValues, numValues);

         for(size_t i = 0; i < names.size(); ++i)
         {
             fs << "{" << "name" << names[i] << "type" << types[i] << "value";
             switch(types[i])
             {
             case CV_8U:
                 fs << (uchar)numValues[i];
                 break;
             case CV_8S:
                 fs << (char)numValues[i];
                 break;
             case CV_16U:
                 fs << (ushort)numValues[i];
                 break;
             case CV_16S:
                 fs << (short)numValues[i];
                 break;
             case CV_32S:
             case CV_MAKETYPE(CV_USRTYPE1,2):
             case CV_MAKETYPE(CV_USRTYPE1,3):
                 fs << (int)numValues[i];
                 break;
             case CV_32F:
                 fs << (float)numValues[i];
                 break;
             case CV_64F:
                 fs << (double)numValues[i];
                 break;
             case CV_USRTYPE1:
                 fs << strValues[i];
                 break;
             default:
                 fs << (double)numValues[i];
                 fs << "typename" << strValues[i];
                 break;
             }
             fs << "}";
         }
     }
     fs << "]";
}

bool FlannBasedMatcher::isMaskSupported() const
{
    return false;
}

Ptr<DescriptorMatcher> FlannBasedMatcher::clone( bool emptyTrainData ) const
{
    Ptr<FlannBasedMatcher> matcher = makePtr<FlannBasedMatcher>(indexParams, searchParams);
    if( !emptyTrainData )
    {
        CV_Error( Error::StsNotImplemented, "deep clone functionality is not implemented, because "
                  "Flann::Index has not copy constructor or clone method ");
        //matcher->flannIndex;
        matcher->addedDescCount = addedDescCount;
        matcher->mergedDescriptors = DescriptorCollection( mergedDescriptors );
        std::transform( trainDescCollection.begin(), trainDescCollection.end(),
                        matcher->trainDescCollection.begin(), clone_op );
    }
    return matcher;
}

void FlannBasedMatcher::convertToDMatches( const DescriptorCollection& collection, const Mat& indices, const Mat& dists,
                                           std::vector<std::vector<DMatch> >& matches )
{
    matches.resize( indices.rows );
    for( int i = 0; i < indices.rows; i++ )
    {
        for( int j = 0; j < indices.cols; j++ )
        {
            int idx = indices.at<int>(i, j);
            if( idx >= 0 )
            {
                int imgIdx, trainIdx;
                collection.getLocalIdx( idx, imgIdx, trainIdx );
                float dist = 0;
                if (dists.type() == CV_32S)
                    dist = static_cast<float>( dists.at<int>(i,j) );
                else
                    dist = std::sqrt(dists.at<float>(i,j));
                matches[i].push_back( DMatch( i, trainIdx, imgIdx, dist ) );
            }
        }
    }
}

void FlannBasedMatcher::knnMatchImpl( InputArray _queryDescriptors, std::vector<std::vector<DMatch> >& matches, int knn,
                                     InputArrayOfArrays /*masks*/, bool /*compactResult*/ )
{
    Mat queryDescriptors = _queryDescriptors.getMat();
    Mat indices( queryDescriptors.rows, knn, CV_32SC1 );
    Mat dists( queryDescriptors.rows, knn, CV_32FC1);
    flannIndex->knnSearch( queryDescriptors, indices, dists, knn, *searchParams );

    convertToDMatches( mergedDescriptors, indices, dists, matches );
}

void FlannBasedMatcher::radiusMatchImpl( InputArray _queryDescriptors, std::vector<std::vector<DMatch> >& matches, float maxDistance,
                                         InputArrayOfArrays /*masks*/, bool /*compactResult*/ )
{
    Mat queryDescriptors = _queryDescriptors.getMat();
    const int count = mergedDescriptors.size(); // TODO do count as param?
    Mat indices( queryDescriptors.rows, count, CV_32SC1, Scalar::all(-1) );
    Mat dists( queryDescriptors.rows, count, CV_32FC1, Scalar::all(-1) );
    for( int qIdx = 0; qIdx < queryDescriptors.rows; qIdx++ )
    {
        Mat queryDescriptorsRow = queryDescriptors.row(qIdx);
        Mat indicesRow = indices.row(qIdx);
        Mat distsRow = dists.row(qIdx);
        flannIndex->radiusSearch( queryDescriptorsRow, indicesRow, distsRow, maxDistance*maxDistance, count, *searchParams );
    }

    convertToDMatches( mergedDescriptors, indices, dists, matches );
}

}

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