⤷ Convert Jpeg-file to bmp-file

Button1Click procedure creates variable of TJPEGImage type and loads a picture stored in a file.
Button2Click procedure creates variable of TBitmap type and sets jpeg object to this variable. s

uses JPEG;
...
var
 JPEGImage: TJPEGImage;
...
procedure TForm1.Button1Click(Sender: TObject);
begin
  JPEGImage:=TJPEGImage.Create;
  if OpenDialog1.Execute then
  begin
    JPEGImage.LoadFromFile(OpenDialog1.FileName);
    Image1.Canvas.Draw(0,0,JPEGImage);
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  Bitmap: TBitmap;
begin
  try
    Bitmap:=TBitmap.Create;
    with Bitmap do
    begin
      PixelFormat:=pf24bit;
      Height:=JPEGImage.Height;
      Width:=JPEGImage.Width;
      Canvas.Draw(0,0, JPEGImage);
    end;
    if SaveDialog1.Execute then
      Bitmap.SaveToFile(SaveDialog1.FileName);
    Label1.Caption:='Convertation finised';
  finally
    Bitmap.Free;
    JPEGImage.Free;
  end;
end;
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