php处理base64编码图片

<br /><br /><span style="font-family: sans-serif; font-size: 16px; background-color: rgb(248, 248, 248);"><?php     </span>

    $data = 'iVBORw0KGgoAAAANSUhEUgAAABwAAAASCAMAAAB/2U7WAAAABl'
      . 'BMVEUAAAD///+l2Z/dAAAASUlEQVR4XqWQUQoAIAxC2/0vXZDr'
      . 'EX4IJTRkb7lobNUStXsB0jIXIAMSsQnWlsV+wULF4Avk9fLq2r'
      . '8a5HSE35Q3eO2XP1A1wQkZSgETvDtKdQAAAABJRU5ErkJggg==';
      $data = base64_decode($data);
      $im = imagecreatefromstring($data);
      if ($im !== false) {
           header('Content-Type: image/png');
           imagepng($im);
           imagedestroy($im);
      }else {
           echo 'An error occurred.';
      }