BCH.BCHTool.getIMG C# (CSharp) Method

        private static Bitmap getIMG(BCHTexture bchtex, byte[] data)
        {
            // New Image
            Bitmap img = new Bitmap(nlpo2(gcm(bchtex.Width, 8)), nlpo2(gcm(bchtex.Height, 8)));
            int f = (int)bchtex.Format;
            int area = img.Width * img.Height;
            if (f == 0 && area > bchtex.Length / 4 || (f == 3 && area > bchtex.Length / 4))
            {
                img = new Bitmap(gcm(bchtex.Width, 8), gcm(bchtex.Height, 8));
                area = img.Width * img.Height;
            }
            byte[] temp = new byte[(int)bchtex.Length];
            Array.Copy(data, bchtex.DataOffset, temp, 0, temp.Length);
            data = temp;
            // Coordinates
            // Colors
            // Tiles Per Width
            int p = gcm(img.Width, 8) / 8;
            if (p == 0) p = 1;
            // Build Image
            using (Stream BitmapStream = new MemoryStream(data))
            using (BinaryReader br = new BinaryReader(BitmapStream))
                for (uint i = 0; i < area; i++) // for every pixel
                {
                    uint x, y;
                    d2xy(i % 64, out x, out y);
                    uint tile = i / 64;

                    // Shift Tile Coordinate into Tilemap
                    x += (uint)(tile % p) * 8;
                    y += (uint)(tile / p) * 8;

                    // Get Color
                    Color c;
                    switch (f)
                    {
                        case 0: //RGBA8 - 4 bytes
                            c = DecodeColor(br.ReadUInt32(), f);
                            break;
                        case 1: //RGB8
                            byte[] data1 = br.ReadBytes(3); Array.Resize(ref data1, 4);
                            c = DecodeColor(BitConverter.ToUInt32(data1, 0), f);
                            break;
                        case 2: //RGBA5551
                        case 3: //RGB565
                        case 4: //RGBA4
                        case 5: //LA8
                            c = DecodeColor(br.ReadUInt16(), f);
                            break;
                        case 6: //HILO8
                        case 7: //L8
                        case 8: //A8
                        case 9: //LA4
                            c = DecodeColor(br.ReadByte(), f);
                            break;
                        case 0xA: //L4
                        case 0xB: //A4
                            uint val = br.ReadByte();
                            img.SetPixel((int)x, (int)y, DecodeColor(val & 0xF, f));
                            i++; x++;
                            c = DecodeColor(val >> 4, f);
                            break;
                        case 0xC:  // ETC1
                        case 0xD:  // ETC1A4
                        default:
                            throw new Exception("Invalid FileFormat.");
                    }
                    img.SetPixel((int)x, (int)y, c);
                }
            return img;
        }