⤷ Convert bmp-file to jpeg-file

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

uses JPEG;
...
var
  Bitmap: TBitmap;
...
procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
  begin
    Bitmap:=TBitmap.Create;
    Bitmap.LoadFromFile(OpenDialog1.FileName);
    Image1.Picture.LoadFromFile(OpenDialog1.FileName);
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  JPEGImage: TJPEGImage;
begin
  try
    JPEGImage:=TJPEGImage.Create;
    JPEGImage.CompressionQuality:=80;
    JPEGImage.Assign(Bitmap);
    if SaveDialog1.Execute then
      JPEGImage.SaveToFile(SaveDialog1.FileName);
    Label1.Caption:='Convertation finished';
  finally
    Bitmap.Free;
    JPEGImage.Free;
  end;
end;
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