/**
         * Detect scale-invariant feature points given a pyramid.
         * @param _i_dog_feature_points
         * 検出したDOG特徴点
         */
        public void detect(GaussianScaleSpacePyramid i_pyramid, DogFeaturePointStack i_dog_feature_points)
        {
            //clean up 1st feature stack
            DogFeaturePointStack tmp_fp = this._tmp_fps;

            tmp_fp.clear();

            // Compute Laplacian images (DoG)
            this.mLaplacianPyramid.compute(i_pyramid);

            // Detect minima and maximum in Laplacian images
            this.extractFeatures(i_pyramid, this.mLaplacianPyramid, tmp_fp);

            // Sub-pixel refinement
            this.findSubpixelLocations(i_pyramid, tmp_fp);

            // Compute the gradient pyramid
            this.mOrientationAssignment.computeGradients(i_pyramid);

            AreaBuckit abuckit = this.mBuckets;


            if (tmp_fp.getLength() <= abuckit._buckit.Length)
            {
                //特徴点の数が要求数以下なら全てのポイントを使う。
                for (int i = 0; i < tmp_fp.getLength(); i++)
                {
                    this.addFeatureOrientations(i_pyramid, tmp_fp.getItem(i), i_dog_feature_points);
                }
            }
            else
            {
                //特徴点を選別(Prune features)

                // Clear the previous state
                abuckit.clear();

                // Insert each features into a bucket
                for (int i = 0; i < tmp_fp.getLength(); i++)
                {
                    DogFeaturePoint p = tmp_fp.getItem(i);
                    abuckit.put(p.x, p.y, i, Math.Abs(p.score));
                }
                // Compute an orientation for each feature point
                for (int i = 0; i < abuckit._buckit.Length; i++)
                {
                    if (abuckit._buckit[i].first == 0)
                    {
                        continue;
                    }
                    this.addFeatureOrientations(i_pyramid, tmp_fp.getItem(abuckit._buckit[i].second), i_dog_feature_points);
                }
            }

            return;
        }
        public static NyARNftFreakFsetFile genFeatureSet3(NyARNftIsetFile i_iset_file)
        {
            int max_features = 500;
            DogFeaturePointStack   _dog_feature_points = new DogFeaturePointStack(max_features);
            FreakFeaturePointStack query_keypoint      = new FreakFeaturePointStack(max_features);
            //
            List <NyARNftFreakFsetFile.RefDataSet> refdataset = new List <NyARNftFreakFsetFile.RefDataSet>();
            List <NyARNftFreakFsetFile.ImageInfo>  imageinfo  = new List <NyARNftFreakFsetFile.ImageInfo>();

            for (int ii = 0; ii < i_iset_file.items.Length; ii++)
            {
                NyARNftIsetFile.ReferenceImage rimg         = i_iset_file.items[ii];
                FREAKExtractor            mFeatureExtractor = new FREAKExtractor();
                int                       octerves          = BinomialPyramid32f.octavesFromMinimumCoarsestSize(rimg.width, rimg.height, 8);
                BinomialPyramid32f        _pyramid          = new BinomialPyramid32f(rimg.width, rimg.height, octerves, 3);
                DoGScaleInvariantDetector _dog_detector     = new DoGScaleInvariantDetector(rimg.width, rimg.height, octerves, 3, 3, 4, max_features);

                //RefDatasetの作成
                _pyramid.build(NyARGrayscaleRaster.createInstance(rimg.width, rimg.height, NyARBufferType.INT1D_GRAY_8, rimg.img));
                // Detect feature points
                _dog_feature_points.clear();
                _dog_detector.detect(_pyramid, _dog_feature_points);

                // Extract features
                query_keypoint.clear();
                mFeatureExtractor.extract(_pyramid, _dog_feature_points, query_keypoint);

                for (int i = 0; i < query_keypoint.getLength(); i++)
                {
                    FreakFeaturePoint ffp = query_keypoint.getItem(i);
                    NyARNftFreakFsetFile.RefDataSet rds = new NyARNftFreakFsetFile.RefDataSet();
                    rds.pageNo     = 1;
                    rds.refImageNo = ii;
                    rds.coord2D.setValue(ffp.x, ffp.y);
                    rds.coord3D.setValue((ffp.x + 0.5f) / rimg.dpi * 25.4f, ((rimg.height - 0.5f) - ffp.y) / rimg.dpi * 25.4f);
                    rds.featureVec.angle  = ffp.angle;
                    rds.featureVec.maxima = ffp.maxima ? 1 : 0;
                    rds.featureVec.scale  = ffp.scale;
                    ffp.descripter.getValueLe(rds.featureVec.v);
                    refdataset.Add(rds);
                }
                imageinfo.Add(new NyARNftFreakFsetFile.ImageInfo(rimg.width, rimg.height, ii));
            }
            NyARNftFreakFsetFile.PageInfo[] pi = new NyARNftFreakFsetFile.PageInfo[1];
            pi[0] = new NyARNftFreakFsetFile.PageInfo(1, imageinfo.ToArray());
            return(new NyARNftFreakFsetFile(refdataset.ToArray(), pi));
        }