修改图片尺寸的DELPHI源代码

function ChangeJpegSize(inFileName, outFileName: string; W, H: Integer): Boolean;

var

  jpg: TJPEGImage;

  bmp: TBitmap;

begin

  Result := False;

  jpg := TJPEGImage.Create;

  try

    jpg.LoadFromFile(inFileName);

    bmp := TBitmap.Create;

    bmp.Width := W;

    bmp.Height := H;

    bmp.Canvas.StretchDraw(Rect(0, 0, bmp.Width, bmp.Height), jpg);

    jpg.Assign(bmp);

    try

      jpg.SaveToFile(outFileName);

      Result := True;

    finally

      bmp.Free;

    end;

  finally

    jpg.Free;

  end;

end;