Please Correct This Error While I Retriving Image From Database

private void Page_Load(object sender, System.EventArgs e)
{
    // Put user code to initialize the page here
    MemoryStream stream = new MemoryStream ();
    SqlConnection connection = new
      SqlConnection (@"...");
    try
    {
        connection.Open ();
        SqlCommand command = new
          SqlCommand ("select Picture from Image", connection);
        byte[] image = (byte[]) command.ExecuteScalar ();  
        stream.Write (image, 0, image.Length);
        Bitmap bitmap = new Bitmap (stream);
        Response.ContentType = "image/gif";
        bitmap.Save (Response.OutputStream, ImageFormat.Gif);
    }
    finally
    {
        connection.Close ();
        stream.Close ();
    }

Error:       byte[] image = (byte[]) command.ExecuteScalar ();   

Unable to cast object of type 'System.Int32' to type 'System.Byte[]'.