The following example demonstrates painting an Icon's image onto a SpeedButton's Glyph. Example:

uses ShellApi;
procedure TForm .FormShow(Sender: TObject);
var
 Icon: TIcon;
begin
  Icon := TIcon.Create;
  Icon.Handle :=
  ExtractIcon(0,
              'C:\WINDOWS\NOTEPAD.EXE',
               );
  SpeedButton .Glyph.Width := Icon.Width;
  SpeedButton .Glyph.Height := Icon.Height;
  SpeedButton .Glyph.Canvas.Draw(0, 0, Icon);
  Icon.Free;
end;