Вопрос Transparent Canvas (Bitmap Image)

[InstallationWay]

I have created a TBitmap Image and I'm filling it in using Canvas.

I need to make it transparent, with no border, and no background color. is this possible? if yes, how?

 [Setup]
AppName = "MyApp"
AppVersion = "1.5"
DefaultDirName = Nothing \
DisableWelcomePage = yes

[Code]
var
  CustomButton: TBitmapImage;

// Drawing
// *************
procedure RedrawCustomButton;
var
  Canvas: TCanvas;
begin
  Canvas: = CustomButton.Bitmap.Canvas;

  Canvas.Pen.Style: = psClear;
  Canvas.Brush.Color: = clBtnFace;
  Canvas.Rectangle (0, 0, CustomButton.Bitmap.Width, CustomButton.Bitmap.Height);

  Canvas.Pen.Style: = psSolid;
  Canvas.Pen.Mode: = pmCopy;
  Canvas.Pen.Color: = clBlack;
  Canvas.Brush.Style: = bsClear;
  Canvas.Rectangle (0, 0, CustomButton.Bitmap.Width, CustomButton.Bitmap.Height);
end;
// *************

procedure InitializeWizard ();
var
  Page: TWizardPage;
begin
  WizardForm.InnerPage.Color: = clYellow;

  Page: = CreateCustomPage (wpWelcome, '', '');

  CustomButton: = TBitmapImage.Create (WizardForm);
  CustomButton.Parent: = Page.Surface;
  CustomButton.Top: = 0;
  CustomButton.Left: = 0;
  CustomButton.Width: = ScaleX (128);
  CustomButton.Height: = ScaleX (32);
  CustomButton.Bitmap.Width: = CustomButton.Width;
  CustomButton.Bitmap.Height: = CustomButton.Height;
  RedrawCustomButton;
end;