1   
2   unit Unit1;
3   
4   interface
5   
6   uses
7     Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
8     Dialogs, StdCtrls,jpeg;
9   
10  type
11    TForm1 = class(TForm)
12      Button1: TButton;
13      procedure Button1Click(Sender: TObject);
14    private
15      { Private declarations }
16    public
17      { Public declarations }
18      procedure JPEGtoBMP(const FileName: TFileName);
19    end;
20  
21  var
22    Form1: TForm1;
23  
24  implementation
25  
26  {$R *.dfm}
27  
28  procedure TForm1.Button1Click(Sender: TObject);
29  begin
30     JPEGtoBMP('C:\test.jpg');
31  end;
32  
33  procedure TForm1.JPEGtoBMP(const FileName: TFileName);
34  var
35    jpeg: TJPEGImage;
36    bmp:  TBitmap;
37  begin
38    jpeg := TJPEGImage.Create;
39    try
40      jpeg.CompressionQuality := 100; {Default Value}
41      jpeg.LoadFromFile(FileName);
42      bmp := TBitmap.Create;
43      try
44        bmp.Assign(jpeg);
45        bmp.SaveTofile(ChangeFileExt(FileName, '.bmp'));
46      finally
47        bmp.Free
48      end;
49    finally
50      jpeg.Free
51    end;
52  end;
53  end.