Flann radiusSearch, knnSearch about javacv HOT 3 CLOSED

I do get random numbers the radiusSearch(), but not for knnSearch(). The 
results are the same, always... Can you double check? If it still does not 
work, please provide more info about your platform, etc. thanks

yes, indeed knn is not generating random numbers.
Though it works extremely inefficient, instead of working faster it works 
slower.
Perhaps you could take a look:
private Integer[] findPairs(CvSURFPoint[] objectKeypoints,
            FloatBuffer[] objectDescriptors, CvSURFPoint[] imageKeypoints,
            FloatBuffer[] imageDescriptors) {

        boolean[] lessRidiculous = new boolean[imageDescriptors.length];
        Integer[] toReturn = new Integer[objectDescriptors.length*2];
        int numNeighbors = 100; 
        int matchCounter = 0;

        LinearIndexParams kdParams = new LinearIndexParams();
        SearchParams searchParams = new SearchParams(descriptorLength, 0.5f, true);

        // Populate imageMat
        CvMat imageMat = CvMat.create(imageDescriptors.length, descriptorLength, CV_32F);
        for (int i = 0; i < imageDescriptors.length; i++) 
        { 
            for (int j = 0; j < descriptorLength; j++) 
            { 
                imageMat.put(i, j, imageDescriptors[i].get(j) ); 
            } 
        } 

        Index flannIndex = new Index(imageMat, kdParams, 1);

        for (int c = 0; c < objectDescriptors.length; c++)
        {
            CvMat queryMat = CvMat.create(1, descriptorLength, CV_32F);

            CvMat indicesMat = CvMat.create(1, numNeighbors, CV_32S);
            CvMat indicesMat = CvMat.create(1, numNeighbors, CV_32S);
            CvMat distancesMat = CvMat.create(1, numNeighbors, CV_32F);
            // Populate queryMat 
            for (int i = 0; i < descriptorLength; i++) 
            { 
                queryMat.put(0, i, (double) objectDescriptors[c].get(i));
            } 
            flannIndex.knnSearch(queryMat, indicesMat, distancesMat, numNeighbors, searchParams);

            //System.out.println("Index " + indicesMat.get(0,0) + " Distance " + distancesMat.get(0,0) + "Index " + indicesMat.get(0,1) + " Distance " + distancesMat.get(0,1));
            int nearestNeighbor = (int)indicesMat.get(0,0);  
            if (indicesMat !=null && nearestNeighbor >0 && nearestNeighbor < imageDescriptors.length && !lessRidiculous[nearestNeighbor])
            {
                lessRidiculous[nearestNeighbor] = true;
                //System.out.println("M " + c + " " + nearestNeighbor  + " d " + distancesMat.get(0,0));
                toReturn[matchCounter++]  = c;
                toReturn[matchCounter++]  = nearestNeighbor ;
            }
        }
        System.out.println("Matches count " + matchCounter);
        return Arrays.copyOf(toReturn, matchCounter); 
        }

Well, CvMat.create() is a pretty heavy operation. You should move those calls 
outside the loop. 

BTW, check out the NetBeans profiler: http://profiler.netbeans.org/ . With that 
tool we can easily find which calls use most of the CPU time.