[JXJ]

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enlace

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You can easily convert a BMP image to a JPG (JPEG) image:
~~~~~~~~~~~~~~~~~~~~~~~~~
{

Código Delphi [-]
Usage:

BMPtoJPG('mybitmap.bmp','myjpeg.jpg')
}

function BMPtoJPG
   (var BMPpic, JPGpic: string):boolean;
var Bitmap: TBitmap;
    JpegImg: TJpegImage;
begin
  Result:=False;
  Bitmap := TBitmap.Create;
  try
   Bitmap.LoadFromFile(BMPpic) ;
   JpegImg := TJpegImage.Create;
   try
    JpegImg.Assign(Bitmap) ;
    JpegImg.SaveToFile(JPGpic) ;
    Result:=True;
   finally
    JpegImg.Free
   end;
  finally
   Bitmap.Free
  end;
end;