unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, StdCtrls,shellapi, ComCtrls, jpeg;type
  TForm1 = class(TForm)
    tb: TTrackBar;
    Image1: TImage;
    procedure FormCreate(Sender: TObject);
    procedure tbChange(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation
{$R *.dfm}procedure TForm1.FormCreate(Sender: TObject);
begin
SetWindowLong(Handle,GWL_EXSTYLE,GetWindowLong(Handle,GWL_EXSTYLE) or $00080000 );
SetLayeredWindowAttributes(Form1.Handle, 0, tb.Position, $00000002);
end;procedure TForm1.tbChange(Sender: TObject);
begin
SetLayeredWindowAttributes(Form1.Handle, 0, tb.Position, $00000002);
end;end.