Zero/ZeroLevel.NN/Examples/tSNE.txt

public static void DrawTSNE(Dictionary<int, int> cluster_map, List<FaceEmbedding> faces)
        {
            double[][] t_snefit_vectors = faces.Select(f => f.Vector.Select(e => (double)e).ToArray()).ToArray();
            TSNE tSNE = new TSNE()
            {
                NumberOfOutputs = 2,
                Perplexity = 100
            };
            // Transform to a reduced dimensionality space
            var embeddings = tSNE.Transform(t_snefit_vectors);
            var xmin = double.MaxValue;
            var xmax = double.MinValue;
            var ymin = double.MaxValue;
            var ymax = double.MinValue;
            for (int i = 0; i < embeddings.Length; i++)
            {
                var lxmin = embeddings[i][0];
                var lxmax = embeddings[i][0];
                if (lxmin < xmin)
                    xmin = lxmin;
                if (lxmax > xmax)
                    xmax = lxmax;

                var lymin = embeddings[i][1];
                var lymax = embeddings[i][1];
                if (lymin < ymin)
                    ymin = lymin;
                if (lymax > ymax)
                    ymax = lymax;
            }

            var norm_x_scale = 1.0f / (xmax - xmin);
            var norm_y_scale = 1.0f / (xmax - xmin);
            var xdiff = 0 - xmin;
            var ydiff = 0 - ymin;
            var centerx = (xmin + xmax) / 2.0f + xdiff;
            var centery = (ymin + ymax) / 2.0f + ydiff;

            var width = 2560;
            var height = 1440;

            var rnd = new Random((int)Environment.TickCount);

            var clusterIds = cluster_map.Values.Distinct().ToArray();
            var cluster_colors = new Dictionary<int, Color>();
            foreach (var cid in clusterIds)
            {
                var color = Color.FromRgb((byte)rnd.Next(0, 255), (byte)rnd.Next(0, 255), (byte)rnd.Next(0, 255));
                cluster_colors[cid] = color;
            }

            using (var image = new Image<Rgb24>(width, height))
            {
                for (int i = 0; i < embeddings.Length; i++)
                {
                    var cluster = cluster_map[i];
                    var color = cluster_colors[cluster];

                    var x = (int)((embeddings[i][0] + xdiff + centerx) * norm_x_scale * width) - width / 2;
                    var y = (int)((embeddings[i][1] + ydiff + centery) * norm_y_scale * height) - height / 2;
                    image.Mutate(im => im.DrawLines(
                        color,
                        4,
                        new PointF[] {
                                        new PointF(x - 1, y - 1),
                                        new PointF(x + 1, y - 1),
                                        new PointF(x + 1, y + 1),
                                        new PointF(x - 1, y + 1),
                                        new PointF(x - 1, y - 1)
                            }
                        ));
                }
                image.SaveAsJpeg(@"G:\FaceTest\tsne.jpeg");
            }
        }