private void OpenToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (ImageFileDialog.ShowDialog() == DialogResult.OK)
            {
                try
                {
                    var bmp = _processor.ConvertToGrayscale(new Bitmap(ImageFileDialog.FileName));
                    _image.OriginalImage = bmp;
                    _image.ViewImage     = bmp;

                    pictureBox1.BorderStyle = BorderStyle.FixedSingle;
                    EnableMenuBarToolstrips();
                    isBinarized = false;
                }
                catch (ArgumentException ex)
                {
                    var extension = ImageFileDialog.FileName.Split('.');
                    MessageBox.Show($"Could not open file with .{extension[extension.Length - 1]} format",
                                    "Warning", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }