求Delphi源代碼：圖像縮放

procedure TForm1.btn1Click(Sender: TObject);

var

tmpbmp:TBitmap;

begin

tmpbmp :=TBitmap.Create;

tmpbmp.Width :=45;//bmp.Width div 2;

tmpbmp.Height :=89;//bmp.Height div 2;

tmpbmp.pixelformat:=pf32bit;

//jpg.PixelFormat:=jf24bit;

tmpbmp.Canvas.StretchDraw(tmpbmp.Canvas.ClipRect,img1.Picture.Graphic );

//img2.Picture.Graphic

img2.Picture.Assign(tmpbmp);

img2.Update ;

end;