private void button3_Click(object sender, EventArgs e) // Segment
        {
            if (!OPEN)
            {
                MessageBox.Show("Please open an image");
                return;
            }

            if (!IMPULSE)
            {
                MessageBox.Show("Please click 'Impulse noise'");
                return;
            }

            SigmaIm = new CImage(OrigIm.width, OrigIm.height, nbyteIm * 8);

            progressBar1.Value = 0;
            SigmaIm.SigmaSimpleUni(ImpulseIm, 1, 30, this);

            ExtremIm = new CImage(OrigIm.width, OrigIm.height, nbyteIm * 8);
            if (nbyteBmp == 3)
            {
                ExtremIm.ExtremVarColor(SigmaIm, 2, this);
            }
            else
            {
                ExtremIm.ExtremLightUni(SigmaIm, 2, this);
            }

            int rv, x, y;

            Palet = new int[256];                               // This is a palette containing an RGB int color for each of 256 indices
            Pal   = new CImage(OrigIm.width, OrigIm.height, 8); // This is an indexed image
            if (ExtremIm.N_Bits == 24)
            {
                rv = Pal.MakePalette(ExtremIm, Palet, this);
            }

            SegmentIm = new CImage(SigmaIm.width, SigmaIm.height, 24);
            Bitmap bmp = new Bitmap(SigmaIm.width, SigmaIm.height, PixelFormat.Format24bppRgb);
            Color  color;

            int PalColor, jump, value;

            if (SigmaIm.height > 300)
            {
                jump = SigmaIm.height / (100 / 6);
            }
            else
            {
                jump = 2;
            }
            progressBar1.Visible = true;
            for (y = 0; y < SigmaIm.height; y++)
            {
                if (y % jump == jump - 1)
                {
                    progressBar1.PerformStep();
                }
                for (x = 0; x < SigmaIm.width; x++)
                {
                    value    = Pal.Grid[x + SigmaIm.width * y];
                    PalColor = Palet[value];
                    color    = Color.FromArgb((PalColor) & 255, (PalColor >> 8) & 255, (PalColor >> 16) & 255);
                    SegmentIm.Grid[2 + 3 * (x + SigmaIm.width * y)] = (byte)(PalColor & 255);
                    SegmentIm.Grid[1 + 3 * (x + SigmaIm.width * y)] = (byte)((PalColor >> 8) & 255);
                    SegmentIm.Grid[0 + 3 * (x + SigmaIm.width * y)] = (byte)((PalColor >> 16) & 255);
                }
            }

            ImageToBitmapNew(SegmentIm, BmpPictBox2); // SegmentIm is always color image but BmpPictBox2 can be indexed
            pictureBox2.Refresh();                    // Image = bmp;

            label3.Text            = "Segmented image, table 'Palet'";
            label3.Visible         = true;
            pictureBox2.Visible    = true;
            progressBar1.Value     = 0;
            button4.Visible        = true;
            label4.Visible         = true;
            numericUpDown3.Visible = true;
            label7.Text            = "Click 'Detect edges'";
            label7.Visible         = true;
            SEGMENTED = true;
        } //********************************* end Segment ******************************************