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install flann and lz4 from github , uninstall the default ones.
sudo apt-get remove liblz4-dev
sudo apt-get remove libflann-dev
CMakeList.txt
cmake_minimum_required(VERSION 2.8)project(testFlann)file(GLOB srcs *.cpp *.hpp *.cc *.h)find_package(Flann REQUIRED)#find_package(HDF5 REQUIRED)include_directories(${FLANN_INCLUDE_DIRS})#include_directories(${HDF5_INCLUDE_DIRS})link_directories(${HDF5_LIBRARY_DIRS})add_executable(${PROJECT_NAME} ${srcs})target_link_libraries(${PROJECT_NAME} ${FLANN_LIBRARIES} lz4 )# ${HDF5_LIBRARIES} main.cpp
//============================================================================// Name : flann-knn-example.cpp// Author : Shohei Yokoyama// Copyright : Shizuoka University, Japan// Description : 1st step of your FLANN application.// Dependency : FLANN http://people.cs.ubc.ca/~mariusm/index.php/FLANN/FLANN// : Boost http://www.boost.org/// : (If win) MinGW & MSYS http://www.mingw.org/// License : NYSL see http://www.kmonos.net/nysl/index.en.html//============================================================================#include #include #include #include using namespace std;using namespace boost;int main(int argc, char** argv) { const int numResult = 2; const int numInput = 100; const int numQuery = 2; const int dimension = 2; const int maxValue = 255; const int minValue = 0; mt19937 gen(static_cast (time(0))); uniform_smallint<> dst(minValue,maxValue); variate_generator > rand(gen, dst); //Calculate the width of values ostringstream ss; ss << (numInput - 1); string s = ss.str(); int lnWidth = s.length(); // for line number ostringstream sss; sss << maxValue; s = sss.str(); int valWidth = s.length(); // for each values ostringstream ssss; ssss << numQuery; s = ssss.str(); int qWidth = s.length(); // for query number cout << "Target Data:" << endl; int targetData[(numInput * dimension)]; for (int i = 0; i < numInput; ++i) { cout.width(qWidth); cout.fill(' '); cout << ' '; cout << "#"; cout.width(lnWidth); cout.fill('0'); cout << i << "\t"; for (int j = 0; j < dimension; ++j) { targetData[i * dimension + j] = rand(); cout.width(valWidth); cout.fill(' '); cout << targetData[i * dimension + j] << "\t"; } cout << endl; } flann::Matrix dataset(targetData, numInput, dimension); int queryData[dimension]; cout << endl << "Query:" << endl; for (int i = 0; i < numQuery; i++) { cout << "Q"; cout.width(qWidth); cout.fill('0'); cout << i; cout.width(lnWidth + 1); cout.fill(' '); cout << " " << "\t"; for (int j = 0; j < dimension; j++) { queryData[(i * dimension) + j] = rand(); cout.width(valWidth); cout.fill(' '); cout << queryData[(i * dimension) + j] << "\t"; } cout << endl; } flann::Matrix query(queryData, numQuery, dimension); flann::Matrix indices(new int[query.rows * numResult], query.rows, numResult); flann::Matrix dists(new float[query.rows * numResult], query.rows, numResult); // construct an randomized kd-tree index using 4 kd-trees flann::Index > index(dataset, flann::KDTreeIndexParams(8)); index.buildIndex(); // do a knn search, using 128 checks index.knnSearch(query, indices, dists, numResult, flann::SearchParams(128)); cout << endl; for (int q = 0; q < numQuery; q++) { for (int r = 0; r < numResult; r++) { cout << "Q"; cout.width(qWidth); cout.fill('0'); cout << q; cout << "#"; cout.width(lnWidth); cout.fill('0'); cout << indices[q][r] << "\t"; for (int j = 0; j < dimension; ++j) { cout.width(valWidth); cout.fill(' '); cout << dataset[indices[q][r]][j] << "\t"; } cout << "dist:" << dists[q][r] << endl; } } //delete[] dataset.ptr();// /delete[] query.ptr(); delete[] indices.ptr(); delete[] dists.ptr();// delete[] query.ptr();// delete[] dataset.ptr(); return 0;}
Target Data: #00 242 16 #01 210 243 #02 211 208 #03 65 180 #04 117 239 #05 52 70 #06 206 215 #07 176 45 #08 44 198 #09 170 11 #10 128 215 #11 205 59 #12 38 101 #13 6 80 #14 154 211 #15 111 225 #16 120 76 #17 244 130 #18 241 109 #19 41 182 #20 8 149 #21 207 34 #22 25 110 #23 142 102 #24 10 119 #25 0 5 #26 116 65 #27 239 134 #28 43 234 #29 225 103 #30 33 121 #31 130 130 #32 204 130 #33 53 132 #34 125 128 #35 231 35 #36 96 111 #37 199 56 #38 161 190 #39 5 224 #40 174 145 #41 6 29 #42 33 146 #43 65 41 #44 188 224 #45 207 139 #46 227 74 #47 20 245 #48 21 155 #49 36 68 #50 130 173 #51 74 93 #52 186 168 #53 102 129 #54 52 250 #55 21 49 #56 83 102 #57 255 186 #58 241 208 #59 78 29 #60 98 140 #61 185 173 #62 133 6 #63 183 195 #64 67 55 #65 27 19 #66 140 48 #67 250 88 #68 147 173 #69 62 26 #70 28 234 #71 136 107 #72 141 162 #73 203 226 #74 249 185 #75 165 162 #76 43 240 #77 54 173 #78 97 35 #79 225 39 #80 150 44 #81 134 1 #82 31 154 #83 132 40 #84 96 200 #85 234 38 #86 59 135 #87 0 141 #88 138 192 #89 34 177 #90 105 27 #91 127 81 #92 67 166 #93 162 131 #94 101 209 #95 23 171 #96 245 120 #97 226 201 #98 251 187 #99 22 225 Query:Q0 123 208 Q1 22 15 Q0#10 128 215 dist:74Q0#15 111 225 dist:433Q1#65 27 19 dist:41Q1#41 6 29 dist:452
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