Converting JPGs to BMPs

From: Christakis John (dontemail_at_me.please.ok)
Date: 11/10/04

  • Next message: Christakis John: "Re: Converting JPGs to BMPs" 
    Date: Wed, 10 Nov 2004 06:52:52 GMT

    Hiya,

    I am trying to do this using streams instead of files. I started with this
    code:

    procedure Jpeg2Bmp(const BmpFileName, JpgFileName: string);
    var
      Bmp: TBitmap;
      Jpg: TJPEGImage;
    begin
      Bmp := TBitmap.Create;
      Jpg := TJPEGImage.Create;
      try
        Jpg.LoadFromFile(JpgFileName);
        Bmp.Assign(Jpg);
        Bmp.SaveToFile(BmpFileName);
      finally
        Jpg.Free;
        Bmp.Free;
      end;
    end;

    and changed it like this:

    try
        jpg.LoadFromStream(stmPhoto);
        Bmp.Assign(Jpg);
        Bmp.SaveToStream(stmBitmap);
    finally
        Jpg.Free;
        Bmp.Free;
    end;

    where stmPhoto is a TStream of a jpeg read from a database blob field and
    stmBitmap is a clean TStream object. I get 'Abstract errors'? Is there an
    easy way to do this? It feels like I am close, but I just can't get it
    working. I have looked at stmBitmap and it appears to contain the Jpeg
    info - there is a 'JFIF' eg.

    tia,
    cj

  • Next message: Christakis John: "Re: Converting JPGs to BMPs"

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