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 2020-03-21 02:10:07 -0500 received badge ● Popular Question (source) 2017-05-10 08:24:12 -0500 commented answer Which norm is the best to match descriptors? Thanks for your answer Berak 2017-05-10 04:17:47 -0500 asked a question Which norm is the best to match descriptors? I am using BFMatcher to compare image descriptors and I'd like to know if there is one particular norm that works best (between L1,L2, L2sqrt). Besides, what's the difference between the two last norms? Are there categories of pictures on which some work better than others ? Where can I find doc about it ? Thanks ! 2017-05-08 11:27:57 -0500 asked a question Difference between BruteForceMatcher_Gpu and BruteForceMatcher_Gpu_base The question is in the title. The first one seem to have no functions... What is the difference between them? Moreover, is it possible to specify a specific norm? Thanks 2017-05-04 09:22:42 -0500 received badge ● Scholar (source) 2017-05-04 07:54:33 -0500 commented question Use extended parameter for Surf descriptor Thanks berak, I thought of that too. I managed to correct it by setting the extended to the extractor, too and it works 2017-05-04 07:15:22 -0500 asked a question Use extended parameter for Surf descriptor Hi, I want to use the extended parameter for Surf algorithm. Here is my code : SurfFeatureDetector detector2(minHessian); detector2.extended=1;  and then extractor2.compute(img, keypoints_4, descriptors2); cout<<"descriptors2 "< keypointsCPU; vector descriptorsCPU; GpuMat descriptors,keypoints; algo(imgGpu,GpuMat(),keypoints,descriptors,false); algo.downloadKeypoints(keypoints, keypointsCPU); algo.downloadDescriptors(descriptors, descriptorsCPU); // from device to host string path; if(j=="requete") path = "requete.txt"; else path = "SURF/" + j.toStdString().substr(0,j.toStdString().find(".")) +".txt"; FileStorage fs(path, FileStorage::WRITE); fs << "SURF" << descriptorsCPU; fs.release(); }  I have the following error message : OpenCV Error: No GPU support (The library is compiled without CUDA support) in mallocPitch, file /build/buildd/opencv-2.4.8+dfsg1/modules/dynamicuda/include/opencv2/dynamicuda/dynamicuda.hpp, line 126 terminate called after throwing an instance of 'cv::Exception' what(): /build/buildd/opencv-2.4.8+dfsg1/modules/dynamicuda/include/opencv2/dynamicuda/dynamicuda.hpp:126: error: (-216) The library is compiled without CUDA support in function mallocPitch though I don't explicitely use Cuda... Here are my includes: #include #include #include #include #include #include #include // #include #include #include #include #include #include #include #include #include #include // for BFMatcher #include #include #include #include #include #include #include  What shall I need to do to get rid of the error ? Thanks !