C# working .with .GIF in transparent form

namespace SplashScreen
{
public partial class frmSplash : Form
{
public frmSplash()
{
InitializeComponent();
}

#region CUSTOM PAINT METHODS ----------------------------------------------
protected override CreateParams CreateParams
{
get
{
CreateParams cp = base.CreateParams;
cp.ExStyle |= 0x00080000; // Required: set WS_EX_LAYERED extended style
return cp;
}
}

//Updates the Form's display using API calls
public void UpdateFormDisplay(Image backgroundImage)
{
IntPtr screenDc = API.GetDC(IntPtr.Zero);
IntPtr memDc = API.CreateCompatibleDC(screenDc);
IntPtr hBitmap = IntPtr.Zero;
IntPtr oldBitmap = IntPtr.Zero;

try
{
//Display-image
Bitmap bmp = new Bitmap(backgroundImage);
hBitmap = bmp.GetHbitmap(Color.FromArgb(0)); //Set the fact that background is transparent
oldBitmap = API.SelectObject(memDc, hBitmap);

//Display-rectangle
Size size = bmp.Size;
Point pointSource = new Point(0, 0);
Point topPos = new Point(this.Left, this.Top);

//Set up blending options
API.BLENDFUNCTION blend = new API.BLENDFUNCTION();
blend.BlendOp = API.AC_SRC_OVER;
blend.BlendFlags = 0;
blend.SourceConstantAlpha = 255;
blend.AlphaFormat = API.AC_SRC_ALPHA;

API.UpdateLayeredWindow(this.Handle, screenDc, ref topPos, ref size, memDc, ref pointSource, 0, ref blend, API.ULW_ALPHA);

//Clean-up
bmp.Dispose();
API.ReleaseDC(IntPtr.Zero, screenDc);
if (hBitmap != IntPtr.Zero)
{
API.SelectObject(memDc, oldBitmap);
API.DeleteObject(hBitmap);
}
API.DeleteDC(memDc);
}
catch (Exception)
{
}
}
#endregion

#region MENU EVENTS -------------------------------------------------------
private void mHomepage_Click(object sender, EventArgs e)
{
System.Diagnostics.Process.Start("http://www.vcskicks.com/");
}

private void mExit_Click(object sender, EventArgs e)
{
this.Close(); //no extra commands are required
}
#endregion

#region FORM EVENTS -------------------------------------------------------
private void Form1_Load(object sender, EventArgs e)
{
UpdateFormDisplay(this.BackgroundImage);
}

protected override void OnPaint(PaintEventArgs e)
{
//Call our drawing function
UpdateFormDisplay(this.BackgroundImage);
}
#endregion
}

internal class API
{
public const byte AC_SRC_OVER = 0x00;
public const byte AC_SRC_ALPHA = 0x01;
public const Int32 ULW_ALPHA = 0x00000002;

[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BLENDFUNCTION
{
public byte BlendOp;
public byte BlendFlags;
public byte SourceConstantAlpha;
public byte AlphaFormat;
}

[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
public static extern bool UpdateLayeredWindow(IntPtr hwnd, IntPtr hdcDst, ref Point pptDst, ref Size psize, IntPtr hdcSrc, ref Point pprSrc, Int32 crKey, ref BLENDFUNCTION pblend, Int32 dwFlags);

[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr GetDC(IntPtr hWnd);

[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);

[DllImport("user32.dll", ExactSpelling = true)]
public static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);

[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern bool DeleteDC(IntPtr hdc);

[DllImport("gdi32.dll", ExactSpelling = true)]
public static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObject);

[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern bool DeleteObject(IntPtr hObject);
}
}