From: anders@melander.dk (Anders Melander)
Subject: Re: Convert 24 bit -> 8 bit, some problems
Date: 15 Feb 1999 00:00:00 GMT
Message-ID: <36c98cd4.14800602@forums.borland.com>
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Alexandre GUILLIEN <aguillien@csi.com> wrote:

>Hello, I have to convert 24 bits bitmaps to smaller 8 bits ones. I use a
>freeware component to convert to make the 24 bits image have only 256
>colors, so the only thing I have to do is to store the bitmap in a 8 bit
>format.

If you don't mind replacing your color reduction library, you can use
the ReduceColors() function in my freeware TGIFImage library. It
produces 8 bit TBitmaps, so all you have to do is:

var
  SourceBitmap,
  DestBitmap: TBitmap;
begin
  SourceBitmap := TBitmap.Create;
  try
    SourceBitmap.LoadFromFile('ManyColors.bmp');
    // Reduce colors to max 256 (2^8)
    DestBitmap := ReduceColors(SourceBitmap, rmQuantize,
      dmFloydSteinberg, 8);
    try
      DestBitmap.SaveToFile('FewColor.bmp');
    finally
      DestBitmap.Free;
    end;
  finally
    SourceBitmap.Free;
  end;
end;

You can find TGIFImage at: http://www.melander.dk/delphi/gifimage/


Thank you for flying Air Melander.

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