高分等你拿，有关图象处理的问题（在线等待）

function bmptobmp(SourceBmpFn,DestBmpFn:string;mulw,mulh:real;w_mm,h_mm:integer):String;  
{mulw和mulh分别是宽和高的倍数。 w_mm和h_mm是指定到多少毫米。当如果w_mm和h_mm有数字时，mulw和mulh就失效了。这是我自己写的一个函数，你可以改一下，或是自己看了，不知道我说清楚了}
var     
  Bmp :TBitmap;
  image1:Timage;
  i:integer;
begin
  result:='';
  try                  
  Bmp :=TBitmap.Create;
  i:=screen.PixelsPerInch;
  image1:=TImage.Create(form);
  image1.Picture.Bitmap.LoadFromFile(sourcebmpfn);
  try
  if (w_mm>0) and (h_mm>0)  then
  begin
      bmp.Width:=round(i*w_mm/25.4);
      bmp.height:=round(i*h_mm/25.4);
  end
  else  if  (mulw>0) and (mulh>0)  then
  begin
       Bmp.Width :=round(image1.Picture.Bitmap.Width*mulw);
       Bmp.Height :=round(image1.Picture.Bitmap.Height*mulh);
  end
  else
  begin
       Bmp.Width :=image1.Picture.Bitmap.Width;
       Bmp.Height :=image1.Picture.Bitmap.Height;
  end;
  except
     exit;
  end;
  SetStretchBltMode(Bmp.Canvas.Handle,HalfTone);
  StretchBlt(Bmp.Canvas.Handle,0,0,Bmp.Width,Bmp.Height,
             Image1.Canvas.Handle,0,0,image1.Picture.Bitmap.Width,image1.Picture.Bitmap.Height,SRCCOPY);
  Image1.Picture.Bitmap.Assign(Bmp);
  if trim(destbmpfn)='' then
  begin
       destbmpfn:=copy(sourcebmpfn,1,pos('.',sourcebmpfn)-1)+'_new.bmp';
  end;
  image1.Picture.SaveToFile(destbmpfn);
  result:=destbmpfn;
  finally
  Bmp.Free;
  image1.Free;
  end;
end;