private void changeLowerLeftConer(string filePath, string newX, string newY)
        {
            FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite);

            int bsCount = 0;
            for (int i = 0; i < stream.Length; i++)
            {
                if (stream.ReadByte() == 13 && stream.ReadByte() == 10)
                {

                    bsCount++;

                    if (bsCount == 2 || bsCount == 3)
                    {
                        Byte[] bytes;
                        if (bsCount == 2)
                        {
                            bytes = System.Text.Encoding.Default.GetBytes("xllcorner "+newX);
                        }
                        else
                        {
                            bytes = System.Text.Encoding.Default.GetBytes("yllcorner "+newY);

                        }
                        stream.Write(bytes, 0, bytes.Length);
                        for (int n = 0; n < stream.Length - stream.Position; n++)
                        {

                            int a = stream.ReadByte();
                            if (a != 13 && a != 32)
                            {
                                stream.Seek(-1, SeekOrigin.Current);
                                stream.Write(new byte[] { 32 }, 0, 1);
                            }
                            else
                            {
                                stream.Seek(-1, SeekOrigin.Current);
                                break;
                            }
                        }

                        if (bsCount == 3)
                        {
                            break;
                        }
                    }
                }
            }

            stream.Close();
        }